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Posted By: rmk1 A1400-8 - 03/10/08 06:34 PM
Since I have posted my comments on just about every other Audio Forum on the Internets :/, I thought it made some sense to post this here. There is not a lot of information regarding the A1400-8 save a couple of informal reviews and Jakeman’s excellent write up here. It is John’s review that prompted me to get the A1400 and after two problem units, I think he was wishing he had not made such a strong recommendation. Well, I’m here to say that I owe you big time John, despite the initial hiccups this amp is everything you said it would be and more. Here is my brief but enthusiastic post of my initial impression of the A1400-8.
 Quote:
The Axiom A1400-8 arrived Saturday. FedEx managed to NOT destroy this one and it took all of 20 minutes to set it up. Axiom feels that there may be an issue with the Audyssey processing so I level matched manually with my Integra DCT 9.8’s test tones and an RS meter and left the Audyssey EQ for later. In my treated room, I’m not convinced there is a noticeable benefit with Audyssey anyway.

I listened to some music, watched some DVD demo discs (familiar material) and a movie I hadn’t seen (Into the Wild) over the weekend. (BTW, Into the Wild is outstanding). Initial impression … I REALLY like what I’m hearing. This Axiom amp is more powerful than my Sunfire 400/5 and in addition to the bigger and more enveloping sound, I am hearing more detail and clarity with the Axiom. I’m searching for analogies and the only one I can come up with is it is more of a “High Definition” sound. I can see that for 2 channel applications people might prefer the organic (read colored) sound of tube amps, but in the digital world in HT applications, these new high current power on demand amps will rule. If you are in the market for a 7 channel digital amp for HT this one (IMHO) is a no brainer. With Axioms 30 day return policy your maximum exposure is shipping one way. Pretty low risk and my guess is you will not be sending this power house amp back.

Audioholics has the A1400-8 in their review cue. I am anxious to see if the A1400-8’s objective data supports my subjective listening impressions.
Here is pic of the amp in place. I love the fact that I can tuck this high powered cool running amp into such a small space. Large mono block amps would not work in my HT.



Posted By: RickF Re: A1400-8 - 03/10/08 06:44 PM
Congrats with the 1400 rmk, beautiful setup and room ... you post on the audioholics site quite often if I'm not mistaken?

Welcome aboard!

Edited to add: I do believe I remember now, this was an upstairs loft that you recently renovated into this new room?
Posted By: EFalardeau Re: A1400-8 - 03/10/08 07:08 PM
Nice room.
My A1400 is also in a flip drawer like that!
Too bad for your first two misfortunes. That amp exceeded my expectations too.
Glad you're joining our little group here! \:\)
Posted By: rmk1 Re: A1400-8 - 03/10/08 07:11 PM
 Originally Posted By: RickF
Congrats with the 1400 rmk, beautiful setup and room ... you post on the audioholics site quite often if I'm not mistaken?

Welcome aboard!

Edited to add: I do believe I remember now, this is an upstairs loft that you recently renovated into this new room?


Hi Rick, yes, I am that post whore :D. I remember you (and that great looking all Axiom HT room of your's) well. We first corresponded back in the early EP-600 days. I got mine just before you as i recall. I really miss that unit. It had a sound that i have not been able to replicate with any other subwoofer (and I've had a few).

It wasn't a loft but just a 20' high open space. I simply built a floor half way up. I need to get some color on the walls this spring as the beige is begining to bug me. The A1400-8 is really a nice product. I will be interested to see if the Axiom folks come out with a "higher end" loudspeaker line to match.
Posted By: rmk1 Re: A1400-8 - 03/10/08 07:18 PM
 Originally Posted By: EFalardeau
Nice room.
My A1400 is also in a flip drawer like that!
Too bad for your first two misfortunes. That amp exceeded my expectations too.
Glad you're joining our little group here! \:\)


Thanks, nice to be here. I actually joined the Forum back in 2005 but had only lurked until now. Actually, Axoim's incredible customer service response to my problem is the reason I stuck with the A1400 and I'm glad I did.
Posted By: StuntGibbon Re: A1400-8 - 03/10/08 07:23 PM
Mine's due in on Wednesday. It'll be driving the epic 80/600 setup. (With an Onkyo TX-NR905 serving as its pre-amp, which I got because I found a price on it that made it cheaper that its non-amplified Integra cousin.)
Posted By: RickF Re: A1400-8 - 03/10/08 07:35 PM
Yessir I do remember us talking about the 600 now, that's been well past a week ago and now that I'm over 50 anything much past, uh, oh I'd say a day or two gets very difficult trying to store and refresh for later use ... I can't even fathom how Jack manages. \:D

Welcome again and don't be a stranger, also keep us posted on the longevity of the 1400, which, sounds like the Axiom folks hit a home run with.
Posted By: rmk1 Re: A1400-8 - 03/10/08 07:36 PM
 Originally Posted By: StuntGibbon
Mine's due in on Wednesday. It'll be driving the epic 80/600 setup. (With an Onkyo TX-NR905 serving as its pre-amp, which I got because I found a price on it that made it cheaper that its non-amplified Integra cousin.)


Good deal, you're gonna love it.

I would not use the Audyssey EQ feature of the 905 at this point. As I mentioned, Axiom feels that this MIGHT have caused the blown channels on my A1400-8. They will be checking out my amp but they had not received it as of this am.
Posted By: rmk1 Re: A1400-8 - 03/10/08 07:42 PM
 Originally Posted By: RickF
Yessir I do remember us talking about the 600 now, that's been well past a week ago and now that I'm over 50 anything much past, uh, oh I'd say a day or two gets very difficult trying to store and refresh for later use ... I can't even fathom how Jack manages. \:D

Welcome again and don't be a stranger, also keep us posted on the longevity of the 1400, which, sounds like the Axiom folks hit a home run with.

Being a bit past 50 myself, let's just say that I get what you're saying. If you want to listen to the Double Trouble album at concert levels, you need one of these amps.

Look at me, this thing has turned me into the pusher man! ;\)




Posted By: StuntGibbon Re: A1400-8 - 03/10/08 07:43 PM
Good to know. I'll pick up an SP meter and do it the old fashioned way. Would you recommend not even striking it up with the audyssey settings I had before? (and just flat it out and start over?)
Posted By: rmk1 Re: A1400-8 - 03/10/08 07:48 PM
 Originally Posted By: StuntGibbon
Good to know. I'll pick up an SP meter and do it the old fashioned way. Would you recommend not even striking it up with the audyssey settings I had before? (and just flat it out and start over?)


Running it as is (not running a new Audyssey calibration) MIGHT be OK but why take the chance? At this point I would just turn Audyssey off and use the old fashion SPL meter approach. Good to have one of those anyway. ;\)
Posted By: StuntGibbon Re: A1400-8 - 03/10/08 08:16 PM
What sort of cables are you using for interconnects? (and does it matter?) \:\)
Posted By: DaveG Re: A1400-8 - 03/10/08 08:42 PM
rmk 1, congrats on the A 1400, thats a really nice looking set-up you have.
Posted By: rmk1 Re: A1400-8 - 03/10/08 08:45 PM
 Originally Posted By: StuntGibbon
What sort of cables are you using for interconnects? (and does it matter?) \:\)


I am using balanced cables (Blue Jeans Cables). The only advantage I can see with balanced is fewer ground loop (hum) issues. While I don't believe that cables should cost hundreds of dollars each, these are expensive components and going cheap on the interconnects isn't a good idea either.
Posted By: EFalardeau Re: A1400-8 - 03/10/08 08:47 PM
Actually, which pre/pro do you have?
Posted By: Ajax Re: A1400-8 - 03/10/08 08:49 PM
I just saw your post on the A1400-8 over at the AV123 forum. Thanks for posting it over there. It's good to see friendly, respectful comments on products other than the home team's. \:\)
Posted By: Ajax Re: A1400-8 - 03/10/08 08:53 PM
 Originally Posted By: RickF
Yessir I do remember us talking about the 600 now, that's been well past a week ago and now that I'm over 50 anything much past, uh, oh I'd say a day or two gets very difficult trying to store and refresh for later use ... I can't even fathom how Jack manages. \:D

Pen and paper are necessities these days. Problem is, I can't remember what I wrote down or where I put the papers.
Posted By: rmk1 Re: A1400-8 - 03/10/08 09:04 PM
 Originally Posted By: Ajax
I just saw your post on the A1400-8 over at the AV123 forum. Thanks for posting it over there. It's good to see friendly, respectful comments on products other than the home team's. \:\)


Thanks Jack, I posted that I was getting the A1400 all over the place and generated some interest. Then after the problems with the first two units I posted that ... so now I feel obliged to make sure that I cover all of those bases by posting about my satisfaction with this excellent amp.

 Quote:
Actually, which pre/pro do you have?


If this question was directed at me, I have the Integra DCT 9.8. It replaced an Emotiva DMC1, that replaced a Parasound C2 (you get the idea ;\) ). No one could ever accuse me of being a brand fan.
Posted By: EFalardeau Re: A1400-8 - 03/10/08 09:18 PM
 Originally Posted By: rmk1
If this question was directed at me, I have the Integra DCT 9.8. It replaced an Emotiva DMC1, that replaced a Parasound C2 (you get the idea ;\) ). No one could ever accuse me of being a brand fan.

Yes, it was directed at you!
Thanks for the response. Slowly looking into this. Very interested by the Athem D2... but if so, it will have to wait as I have started saving for the biggest HT improvement of all for me: a house (no neighbors!).
Posted By: rmk1 Re: A1400-8 - 03/10/08 09:31 PM
 Originally Posted By: EFalardeau
 Originally Posted By: rmk1
If this question was directed at me, I have the Integra DCT 9.8. It replaced an Emotiva DMC1, that replaced a Parasound C2 (you get the idea ;\) ). No one could ever accuse me of being a brand fan.

Yes, it was directed at you!
Thanks for the response. Slowly looking into this. Very interested by the Athem D2... but if so, it will have to wait as I have started saving for the biggest HT improvement of all for me: a house (no neighbors!).


I understand completely. I just built out a dedicated HT space this past fall and it has given me the freedom to do as I see fit with all of this AV gear. No WAF issues .
Posted By: SirQuack Re: A1400-8 - 03/10/08 11:09 PM
rmk, welcome \:\)

I know you had some reservations on AVSForum after your problems, I'm glad you have changed your tune on the 1400.


Posted By: dllewel Re: A1400-8 - 03/11/08 10:18 PM
Hi rmk,

Thanks for the nice review. I hope you continue to enjoy the amp.
Posted By: rmk1 Re: A1400-8 - 03/12/08 01:03 AM
 Originally Posted By: dllewel
Hi rmk,

Thanks for the nice review. I hope you continue to enjoy the amp.


Thanks Dave, even with the Audyssey issue (if that's what it is) I'm pretty sure that the A1400-8 will be a fixture in my HT for a quite a while.
Posted By: StuntGibbon Re: A1400-8 - 03/12/08 01:08 AM
At what levels do you start to really detect a difference from your older setup? Obviously it should be able to really push at high volumes, but do you notice any differences on the lower ends too?
Posted By: SirQuack Re: A1400-8 - 03/12/08 01:14 AM
According to other 1400 owners, yes.
Posted By: rmk1 Re: A1400-8 - 03/12/08 01:52 AM
 Originally Posted By: StuntGibbon
At what levels do you start to really detect a difference from your older setup? Obviously it should be able to really push at high volumes, but do you notice any differences on the lower ends too?


My Sunfire amp is a very good high current amp (600 WPC @ 6 Ohms). Someone going from an AVR might notice more of a difference than I have at lower SPL's. That said, I was looking for an amp that could handle the dynamics of modern movie sound tracks and that is the sweet spot for this amp. I have also been impressed with rock concert DVD's and orchestral pieces. Anything with a lot of layers and complexity is handled better by the A1400-8 than any other amplifier I have experienced.
Posted By: ihifi Re: A1400-8 - 03/12/08 03:07 AM
The higher the SPL, the bigger the difference I noticed between the A1400-8 and the Yamaha DSP-A1 (110w/channel). At SPLs above say 65-75dB, you no longer need blind testing in my room; the difference hits you and puts a grin on your face. The amp can take the M80s to a level of performance at high SPLs that I never experienced or believed possible with the Yamaha. What I also found surprising was that despite the high SPL levels, my ears felt satisfied rather than disturbed; i.e., that sense of disturbance one feels from loudness did not seem to exist at SPLs that I knew would with the Yamaha (likely from clipping, distortion, and compression). At lower SPLs, I think I hear a difference, but I would prefer blind testing to be sure. I have never owned a separate amp before and honestly all the amps that I auditioned (Krell TAS, Anthem A5, Lexicon LX-7, Classe, and some others) in different rooms sounded wonderful to me. Lets just say that to my untrained and very biased ears, the A1400-8 sounds at least as good as these.

John
Posted By: haylo75 Re: A1400-8 - 03/12/08 03:59 AM
Good thread here. Coming from a Rotel RSX-1057 to the A1400-8, I could tell a difference in transients typical of action movie soundtracks even at moderate volumes, where peaks were less than 90dB at the listening position. Bass reproduction is where it really makes a difference IMO. I can recall only one time where I was able to drive my M80's to audible distortion while using the A1400-8, and that was at an ungodly high volume (110dB continuous). I auditioned a Rotel RB-1080 2 channel amp for a weekend and, while it drove the M80s well, I was able to trigger its thermal protection circuit without a hell of a lot of effort. I suppose the RB-1092 would've been a fairer comparison, but it wasn't available at the time of my audition. My current A1400-8 doesn't ever get too hot, though I had a channel go out on my previous one due to what Axiom believed was thermal failure. I'm following up with them now, especially after reading RMK's messages about Audyssey possibly being a factor.
Posted By: Mojo Re: A1400-8 - 03/12/08 04:11 AM
I presume then that the bass reproduction benefit is not realized when the system includes a powered sub.
Posted By: Kpt_Krunch Re: A1400-8 - 03/12/08 04:12 AM
Hey RMK - thanks for posting here. I really like the fact you had problems with the first two. Don't get me wrong, I'd hope you and everyone else would have zero problems, but you don't know how a company will stand behind a product until problems arise. Though the internet is a very very small place, and if a company didn't stand behind their products, they wouldn't be around long.

Hopefully this amp will last you. One nice thing I've found about electronics, especially amps - if they're good out of the box, they should be good for years to come.

The Audessy thing doesn't sit right with me though. Did the good folks over at Axiom indicate they'd get back to you with why (if) Audessy affects their amps. I assume Audessy (never had a processor that used it) put out a certain type of testtone not liked by the amp, or else what else does it do?

Also, and forgive my ignorance here, but why would you have to re-calibrate your system? I thought the amp would just supply the power required by the speakers based on the volume level set by the processor. I could see if you got a different processor, but why do it for a different amp? I put a 100 w/channel HK PA2000 (bridged) to my mains. When I eq'd it afterwords (with an RS analog meter) there were no adjustments required, sounded the same. However, at louder volumes there's no breakup in the sound (where I feel the difference comes in).

So if you (or anyone else here) cam enlighten me as to why you'd eq your whole system with an amp change, I'm all ears.... so to speak \:\)

Thanks again for sharing your thoughts RMK .... this amp could very well find a home in my h/t once I'm ready to buy!
Posted By: rmk1 Re: A1400-8 - 03/12/08 05:39 AM
 Originally Posted By: Kpt_Krunch
Hey RMK - thanks for posting here. I really like the fact you had problems with the first two. Don't get me wrong, I'd hope you and everyone else would have zero problems, but you don't know how a company will stand behind a product until problems arise. Though the internet is a very very small place, and if a company didn't stand behind their products, they wouldn't be around long.

Hopefully this amp will last you. One nice thing I've found about electronics, especially amps - if they're good out of the box, they should be good for years to come.

The Audessy thing doesn't sit right with me though. Did the good folks over at Axiom indicate they'd get back to you with why (if) Audessy affects their amps. I assume Audessy (never had a processor that used it) put out a certain type of testtone not liked by the amp, or else what else does it do?

Also, and forgive my ignorance here, but why would you have to re-calibrate your system? I thought the amp would just supply the power required by the speakers based on the volume level set by the processor. I could see if you got a different processor, but why do it for a different amp? I put a 100 w/channel HK PA2000 (bridged) to my mains. When I eq'd it afterwords (with an RS analog meter) there were no adjustments required, sounded the same. However, at louder volumes there's no breakup in the sound (where I feel the difference comes in).

So if you (or anyone else here) cam enlighten me as to why you'd eq your whole system with an amp change, I'm all ears.... so to speak \:\)

Thanks again for sharing your thoughts RMK .... this amp could very well find a home in my h/t once I'm ready to buy!


You're welcome \:\) , I have run Audyssey many times (cause I can ;\) ) with slightly different results each time. Adding a more powerful amp and two new surround speakers (5.1 to 7.1) made running Audyssey again necessary as I wanted to use the EQ feature of my Integra 9.8to set the levels and distance of the new speakers. Honestly, I don't miss the Audyssey EQ but would like an explanation.
Posted By: Ajax Re: A1400-8 - 03/12/08 03:25 PM
Hi Kpt. You turn up in the strangest places. ;\)
Posted By: jakeman Re: A1400-8 - 03/12/08 04:53 PM


Rob, I'm glad to see you toughed it out and let Axiom's excellent service deal with the problems you were having. \:\) It really is a phenomenal amp and IMO has set a new benchmark performance for Class D amps. I've had a couple of chats with Tom about the Audessey problem. Making a long discussion short it has to do with how the new program in the Integra 9.8 flucuates higher amounts of voltage which prompts a safety shutdown. Its hard to say whether its the fault of the Audessey or Axiom's safety precautions. Other folks like ihifi (John) have use the Audessey in the Onkyo 905 without problem.

In any event I've always felt the Audessey programs were not very good and very overhyped so I never use them.
Posted By: Mojo Re: A1400-8 - 03/12/08 05:11 PM
Next time you talk with Tom, it may not be a bad idea to mention that input specifications for the amp may make it easier for the consumer to avoid incompatibilities.
Posted By: EFalardeau Re: A1400-8 - 03/12/08 05:34 PM
A1400-8 specs says 1.5VRMS for input.
Posted By: Mojo Re: A1400-8 - 03/12/08 05:54 PM
Then if the Integra is outputting more than 1.5VRMS for Audyssey purposes, there's likely an incompatibility.

Did you find that spec in the manual?
Posted By: alan Re: A1400-8 - 03/12/08 06:38 PM
 Originally Posted By: rmk1
Adding a more powerful amp and two new surround speakers (5.1 to 7.1) made running Audyssey again necessary as I wanted to use the EQ feature of my Integra 9.8to set the levels and distance of the new speakers. Honestly, I don't miss the Audyssey EQ but would like an explanation.


Hello all,

I just chatted with Tom Cumberland at Axiom about the issues with running Audyssey and the A1400-8, and here, slightly modified, is his explanation of what is happening, which confirms my own gut suspicions about what is occurring:

"The way Audyssey sets up the system is to increase the volume level to the amp until it ‘hears’ something. With an amp as powerful as the A-1400, this is a very dangerous approach. If the amp ‘sees’ more than 2.0 VRMS on the input (1.5VRMS is the standard for full power output of the A1400-8), it will more than likely do some damage somewhere. We believe that if the customer uses the manual setup to adjust the levels, he is unlikely to do any damage to either his speakers or the amplifier. The A-1400 is designed to follow the standard with a 1.5VRMS input producing full power output, and 1.7VRMS input as the clipping point. As you can see by the numbers, a little bit more input to the A1400 translates to a really big change in the amplifier's output. This is true for all very high powered amplifiers, ours included."

Regards,

Alan
Posted By: EFalardeau Re: A1400-8 - 03/12/08 06:38 PM
Yes, it is in the manual.
The trouble is to find the specs of pre-out on receivers and preamps.
Posted By: Mojo Re: A1400-8 - 03/12/08 06:41 PM
My Denon has a "rated" output of 1.2V. By rated, I assume Denon means maximum. And I assume that's RMS.
Posted By: alan Re: A1400-8 - 03/12/08 06:54 PM
 Originally Posted By: Mojo
My Denon has a "rated" output of 1.2V. By rated, I assume Denon means maximum. And I assume that's RMS.


Hi Mojo,

In a perfect world, all manufacturers would adhere to the standard line-level preamp and AV preamp output levels in order to ensure compatibility between different components. However, I can tell you from my days bench-testing gear for a Canadian AV magazine, that so-called "standard" output levels varied all over the place. I sometimes measured preamp outputs as high as 7 or 8 volts, which would overload the input section of any amplifier.

It would be interesting to actually measure a Denon or Integra's preamp output levels when Audyssey is operating. . .

Regards,

Alan
Posted By: Ken.C Re: A1400-8 - 03/12/08 06:56 PM
I don't know if I would use the word "interesting" as much as "important."
Posted By: StuntGibbon Re: A1400-8 - 03/12/08 07:05 PM
 Originally Posted By: alan
 Originally Posted By: Mojo
My Denon has a "rated" output of 1.2V. By rated, I assume Denon means maximum. And I assume that's RMS.


Hi Mojo,

In a perfect world, all manufacturers would adhere to the standard line-level preamp and AV preamp output levels in order to ensure compatibility between different components. However, I can tell you from my days bench-testing gear for a Canadian AV magazine, that so-called "standard" output levels varied all over the place. I sometimes measured preamp outputs as high as 7 or 8 volts, which would overload the input section of any amplifier.

It would be interesting to actually measure a Denon or Integra's preamp output levels when Audyssey is operating. . .

Regards,

Alan


You wouldn't happen to know anyone with the tools to pull that off would you? This seems like good information for us to have so there aren't so many returns on a $3800 unit.
Posted By: Dundas Re: A1400-8 - 03/12/08 07:22 PM
I was going to order an A1400-8 today then I run across this information. Not being able to use Audyssey is a deal breaker for me! My problem is that even if it works OK with my Denon AVR-3806 I am planning to replace it shortly (but maybe not within 30 days depending on firmware developments) with an Onkyo 885. I don't know where this leaves me. Why is Axiom the only one with this issue?
Posted By: alan Re: A1400-8 - 03/12/08 07:26 PM
 Originally Posted By: kcarlile
I don't know if I would use the word "interesting" as much as "important."


Yeah, "interesting" is a euphemism I use when I'm trying to avoid saying something offensive. A more precise phrase in this context would be "highly revealing."

Alan
Posted By: Mojo Re: A1400-8 - 03/12/08 07:28 PM
I am sure Tom will come up with an answer soon. The most difficult part of this is understanding the problem.
Posted By: rmk1 Re: A1400-8 - 03/12/08 07:35 PM
 Originally Posted By: jakeman


Other folks like ihifi (John) have use the Audessey in the Onkyo 905 without problem.

In any event I've always felt the Audessey programs were not very good and very overhyped so I never use them.



Hi John, actually ihifi has not used Audyssey and was waiting (like me) for a more definitive answer. Since Denon, Onkyo and others are using versions of the Audyssey EQ it would seem to me that Axiom would want to ensure compatibility. Even though I have had mixed results with Audyssey, I am not ready to abandon it as an option on my processor and would hope that Axiom is working toward a solution.
Posted By: EFalardeau Re: A1400-8 - 03/12/08 07:40 PM
Actually, John meant me and the 805! \:\)
There might be some built-in limits when Audessey is used in an integrated receiver as to not overload its specified limits.
Posted By: Dundas Re: A1400-8 - 03/12/08 07:55 PM
 Originally Posted By: EFalardeau

There might be some built-in limits when Audessey is used in an integrated receiver as to not overload its specified limits.


There are the Integra, Onkyo and NAD PrePros as well as all the AVRs that are being used as PrePros (mine included) without any reported issues. This problem seems to be unique to Axiom.
Posted By: jakewash Re: A1400-8 - 03/12/08 08:01 PM
Digital amp compared to analog with regards to why Axiom?
Posted By: Dundas Re: A1400-8 - 03/12/08 08:06 PM
 Originally Posted By: jakewash
Digital amp compared to analog with regards to why Axiom?

There are lots of other digital amps.
Posted By: SirQuack Re: A1400-8 - 03/12/08 08:10 PM
The other digital amps are designed differently than the Axiom.
Posted By: ihifi Re: A1400-8 - 03/12/08 08:14 PM
 Originally Posted By: jakeman


Rob, I'm glad to see you toughed it out and let Axiom's excellent service deal with the problems you were having. \:\) It really is a phenomenal amp and IMO has set a new benchmark performance for Class D amps. I've had a couple of chats with Tom about the Audessey problem. Making a long discussion short it has to do with how the new program in the Integra 9.8 flucuates higher amounts of voltage which prompts a safety shutdown. Its hard to say whether its the fault of the Audessey or Axiom's safety precautions. Other folks like ihifi (John) have use the Audessey in the Onkyo 905 without problem.

In any event I've always felt the Audessey programs were not very good and very overhyped so I never use them.



I actually have the Integra DTC-9.8, not the Onkyo 905, and have never used Audyysey room EQ/correction. It may have been someone else that you are remembering.

John
Posted By: jakeman Re: A1400-8 - 03/12/08 08:16 PM
Thanks for chiming in Eric. ;\) John, Eric and myself have had a long mail thread going about the a1400-8. I presumed both of you had run Audessey but I see from rereading it that it was Eric and not John. Interesting that you did not have a problem with the 805.
Posted By: rmk1 Re: A1400-8 - 03/12/08 08:22 PM
 Originally Posted By: Dundas
 Originally Posted By: jakewash
Digital amp compared to analog with regards to why Axiom?

There are lots of other digital amps.


True but the Audyssey EQ is a relatively new technology and has only recently been added to these various AVR's and SSP's. It just may be that the problem exists more globally with other high current amps and has been misdiagnosed. I can say that I had no issues with my Sunfire amp and Audyssey. IMHO, there is insufficient data to support any strong conclusions. I will continue to as John said “tough it out”, but I am looking for resolution.
Posted By: jakeman Re: A1400-8 - 03/12/08 08:23 PM
 Originally Posted By: Dundas
I was going to order an A1400-8 today then I run across this information. Not being able to use Audyssey is a deal breaker for me! My problem is that even if it works OK with my Denon AVR-3806 I am planning to replace it shortly (but maybe not within 30 days depending on firmware developments) with an Onkyo 885. I don't know where this leaves me. Why is Axiom the only one with this issue?


I'm down at my place in Sanibel, FL for a couple of weeks and a friend of mine down here has the 885/1400-8 combo driving 3 VP150s and 4 QS8s. Like myself he believes in using manual equalization sparingly, so he's never run Audessey. The sound is fantastic. I'll try to post some pics later.
Posted By: Dundas Re: A1400-8 - 03/12/08 08:31 PM
I think that Axiom needs to get out in front of this issue in a hurry. Is the A1400-8 incompatible with Audyssey?
With other automated setup and equalization systems (which is where the market is going)?
What exactly are the issues (I did not find Alan Lofft’s explanation sufficient)?
If I understand correctly the problem is the setup procedure not the on-going use of Audyssey? Is there any work around?
Not many people are going to buy something this expensive from an internet based company without doing some research and as this potential negative spreads (and grows in the telling) it is not going to be very good for sales.
Posted By: rmk1 Re: A1400-8 - 03/12/08 08:32 PM
 Originally Posted By: jakeman
 Originally Posted By: Dundas
I was going to order an A1400-8 today then I run across this information. Not being able to use Audyssey is a deal breaker for me! My problem is that even if it works OK with my Denon AVR-3806 I am planning to replace it shortly (but maybe not within 30 days depending on firmware developments) with an Onkyo 885. I don't know where this leaves me. Why is Axiom the only one with this issue?


I'm down at my place in Sanibel, FL for a couple of weeks and a friend of mine down here has the 885/1400-8 combo driving 3 VP150s and 4 QS8s. Like myself he believes in using manual equalization sparingly, so he's never run Audessey. The sound is fantastic. I'll try to post some pics later.

I'm afraid that the Audyssey doesn't work so why use it theory will not help Axiom sell A1400-8's. Come on John, tell your friend to man up and run Audyssey just to see what happens
Posted By: rmk1 Re: A1400-8 - 03/12/08 08:40 PM
 Originally Posted By: Dundas
I think that Axiom needs to get out in front of this issue in a hurry. Is the A1400-8 incompatible with Audyssey?
With other automated setup and equalization systems (which is where the market is going)?
What exactly are the issues (I did not find Alan Lofft’s explanation sufficient)?
If I understand correctly the problem is the setup procedure not the on-going use of Audyssey? Is there any work around?
Not many people are going to buy something this expensive from an internet based company without do some research and as this potential negative spreads (and grows in the telling) it is not going to be very good for sales.


Unfortunately, I agree with you but I am happy enough with the performance of the A1400-8 that if it were to come down to an either or situation I'm not sure how I would go. At this point I see more tangible benefits from the A1400-8 than the Audyssey EQ. I would prefer not having to make that choice.
Posted By: haylo75 Re: A1400-8 - 03/12/08 08:45 PM
 Originally Posted By: Mojo
I presume then that the bass reproduction benefit is not realized when the system includes a powered sub.
It can be if you still don't bass manage your mains.
Posted By: EFalardeau Re: A1400-8 - 03/12/08 08:48 PM
 Originally Posted By: haylo75
 Originally Posted By: Mojo
I presume then that the bass reproduction benefit is not realized when the system includes a powered sub.
It can be if you still don't bass manage your mains.

The sub also only take care of the extremely low frequencies. Most of the bass is still coming from the regular speakers.
Posted By: jakeman Re: A1400-8 - 03/12/08 08:55 PM
I'm sure Tom et al. are researching it. It would be interesting to see if other Class D amps also have this problem or whether it is unique to the design of the a-1400-8. Regardless, running Audessey should not be a worry for anyone owning this amp.

As for the market going all auto setup and equalization, I doubt that is right. I know Audessey likes to talk that up but I've checked out those programs many times in many different HT systems. I can say every one was screwed up and sounded better without the Audessey settings.

A few years ago I was quite intrigued with them and had long chats with the Anthem engineers about why they were not using auto-equalization in their excellent processors. I was looking at the D1 at the time. Anthem's extensive research showed much the same thing as my observations. All too often listeners percieve a momentary audible change in FR in room as somehow improving sound quality. The basic problem with Audessey and other programs stems from the fact that no receiver/processor around today has the computational power required to run enough iterations while running sweeps. The auto programs that come close are those pro programs that rely on powerful desktop computers and require an hour or so to find optimal settings. That doesn't happen in a receiver auto setup.

To make matters worse, those auto programs introduce considerable phase problems. So you go from having well designed speaker FR and dealing with natural room acoustics to electronically induced aberrations in FR and screwed up time domain. No thanks.

I remain hopeful one day there will be an auto-setup program that gets it right. With the increasing power of small chips that may happen sooner rather than later but its not available today.
Posted By: jakeman Re: A1400-8 - 03/12/08 09:07 PM
 Originally Posted By: rmk1


I'm afraid that the Audyssey doesn't work so why use it theory will not help Axiom sell A1400-8's. Come on John, tell your friend to man up and run Audyssey just to see what happens


It doesn't matter to me about whether that theory sells Axioms or not. \:\) My consistent postion for a long time is that Audessey and auto equalization are just expensive placebos (ie marketing ploys) which certain manufacturers use to sell receivers. Another example of the same problems: you've used the SMS auto equalization I'm sure. Those settings didn't look very pretty did they? I do agree that the amp shouldn't shutdown though from running it.

Now with regards to my friend, I'll see if he is man enough to run Audessey after a few mojitos.
Posted By: rmk1 Re: A1400-8 - 03/12/08 09:10 PM
 Originally Posted By: jakeman
[quote=rmk1]Now with regards to my friend, I'll see if he is man enough to run Audessey after a few mojitos.


You mean a few more, don't you? \:D
Posted By: jakeman Re: A1400-8 - 03/12/08 09:12 PM
Ok after a few more. You counting?
Posted By: rmk1 Re: A1400-8 - 03/12/08 09:17 PM
 Originally Posted By: jakeman
 Originally Posted By: rmk1


I'm afraid that the Audyssey doesn't work so why use it theory will not help Axiom sell A1400-8's. Come on John, tell your friend to man up and run Audyssey just to see what happens


It doesn't matter to me about whether that theory sells Axioms or not. \:\) My consistent postion for a long time is that Audessey and auto equalization are just expensive placebos (ie marketing ploys) which certain manufacturers use to sell receivers. Another example of the same problems: you've used the SMS auto equalization I'm sure. Those settings didn't look very pretty did they? I do agree that the amp shouldn't shutdown though from running it.


Well marketing hype or sound engineering/programming aside, the guys that sell thousands of units per month (Denon, Onkyo and Marantz) are all drinking the Audyssey Koolaid.

BTW, my settings were perfect for my imperfect space and taste. \:\)
Posted By: jakeman Re: A1400-8 - 03/12/08 09:41 PM
Glad it worked for you. The only place I use any equalization is for subs and not so much. These days with four subs, I don't use any.

By the way I'm not anti-Audessey, just anti-hype. I'm keeping an eye on their latest product, Audessey MultiEQ, which is supposed to cure time and frequency domain issues and also allows for implementation with a home computer. If that works as suggested I'll be buying it. Until then I'll avoid placebos.

Anyway I'm off to cook some sea trout we caught in the Gulf this afternoon. \:\)
Posted By: haylo75 Re: A1400-8 - 03/12/08 09:42 PM
This has become quite an interesting discussion. Based on Tom's statement via Alan, I am now concerned that I have may have damaged to my speakers as I have run the Audyssey setup routine with 8 listening positions at least a half dozen times. I am now using another A1400-8 after having used Audyssey for awhile on a prior A1400-8 and having a channel go bad. Brent at Axiom said that Tom thought it sounded like the failure was heat related, nad I followed up with an e-mail but haven't heard anything back in terms of diagnosis.

I heard distortion out of the tweeters on my VP150 the other night while watching a boxing match on HBO HD. The issue didn't subside even at low volume levels, and I was forced to turn the ReEQ feature on my processor on in order to avoid the distortion. Funny thing was, the distortion was almost exclusively limited to when Max Kellerman was speaking. Maybe he was leaning too closely to his mic and/or the source was clipping.

I've watched some shows and listened to music since that night and haven't heard the issue recur. The issue really sticks out in my head at the moment since I just read this thread.

My experiences with Audyssey notwithstanding, I feel that any amp vendor puts themselves in a precarious position stating that EQ software being integrated by a number of pre/pro vendors is not compatible with their product. Axiom has provided some of the best customer service that I have received from any vendor in any industry, so I for one don't believe they consider the matter settled after Tom -> Alan's statement in this thread.
Posted By: Mojo Re: A1400-8 - 03/12/08 09:47 PM
What exactly are they saying about curing frequency AND time domain issues. Frequency and time are really one and the same since they are related by the speed of sound.
Posted By: Mojo Re: A1400-8 - 03/12/08 09:59 PM
I love the way Axiom markets products. They'll intentionally design a new product with a "bug" that has seemingly endless engineering implications, deliver a few hoping that someone discovers it, wait until everyone in the world hears about it over the net and then magically release the solution pleasing all owners thereby converting them into Axiom heralds. It's brilliant \:\) !
Posted By: rmk1 Re: A1400-8 - 03/13/08 01:16 AM
 Originally Posted By: Mojo
I love the way Axiom markets products. They'll intentionally design a new product with a "bug" that has seemingly endless engineering implications, deliver a few hoping that someone discovers it, wait until everyone in the world hears about it over the net and then magically release the solution pleasing all owners thereby converting them into Axiom heralds. It's brilliant \:\) !


Do you work for Axiom? Director of Marketing perhaps?
Talk about shameless self promotion.
Posted By: RickF Re: A1400-8 - 03/13/08 01:20 AM
 Originally Posted By: rmk1
 Originally Posted By: Mojo
I love the way Axiom markets products. They'll intentionally design a new product with a "bug" that has seemingly endless engineering implications, deliver a few hoping that someone discovers it, wait until everyone in the world hears about it over the net and then magically release the solution pleasing all owners thereby converting them into Axiom heralds. It's brilliant \:\) !


Do you work for Axiom? Director of Marketing perhaps?
Talk about shameless self promotion.


I've often wondered that very thought myself.
Posted By: rmk1 Re: A1400-8 - 03/13/08 01:53 PM
 Originally Posted By: EFalardeau
Actually, John meant me and the 805! \:\)
There might be some built-in limits when Audessey is used in an integrated receiver as to not overload its specified limits.


Thank you for the clarification. So just to be clear on this, you have run the Audyssey EQ on your 805 while connected to the A1400-8 with no issues correct? How many LP's did you run it for and have you repeated the overall process, or only run it once?
Thanks again,
Rob
Posted By: EFalardeau Re: A1400-8 - 03/13/08 02:31 PM
Yes, I ran the Audyssey EQ with my 805 connected to A1400 connected to 7 speakers (8 counting double center ion parallel). It was a single pass (3 seats).

The only reason why I did it (I never like the result of auto-eq) is that after having to move my right M80 closer to the side wall---it was then 12"/12" with a fairly strong toe-in---it felt like a booming hump in the bass. To make sure I was not hallucinating, I ran the auto-eq and the problem disappeared (but then the sound was just off... not to say awfull). I then reset the parameters and tried some manual EQ.

As soon as I confirmed that my ears were not deceiving me (and that they was something wrong at around 90hz), I solved the problem by moving changing the angle with the corner of my right M80---now 9.5"/13" with a less toe-in---until the bass sounded right again. After that, reset everything to normal, confirm with SPL in hand, and voilà! great sound again! \:\)
Posted By: rmk1 Re: A1400-8 - 03/13/08 04:54 PM
 Originally Posted By: EFalardeau
Yes, I ran the Audyssey EQ with my 805 connected to A1400 connected to 7 speakers (8 counting double center ion parallel). It was a single pass (3 seats).

The only reason why I did it (I never like the result of auto-eq) is that after having to move my right M80 closer to the side wall---it was then 12"/12" with a fairly strong toe-in---it felt like a booming hump in the bass. To make sure I was not hallucinating, I ran the auto-eq and the problem disappeared (but then the sound was just off... not to say awfull). I then reset the parameters and tried some manual EQ.

As soon as I confirmed that my ears were not deceiving me (and that they was something wrong at around 90hz), I solved the problem by moving changing the angle with the corner of my right M80---now 9.5"/13" with a less toe-in---until the bass sounded right again. After that, reset everything to normal, confirm with SPL in hand, and voilà! great sound again! \:\)



Thank you for the detailed reply. This certainly lends some credence to your theory that there is some form of limiter for the AVR units that does not exist for the SSP’s. Of course that assumes that Audyssey is the cause of my blown channels in the first place.

Not sure that all this speculation and conjecture is productive but heck we are hobbyists and that sort of comes with the job, doesn’t it. ;\)

Posted By: jakewash Re: A1400-8 - 03/13/08 07:08 PM
 Originally Posted By: rmk1


Not sure that all this speculation and conjecture is productive but heck we are hobbyists and that sort of comes with the job, doesn’t it. ;\)
It at least makes for good reading.
Posted By: jakeman Re: A1400-8 - 03/13/08 09:16 PM
Well not exactly, Tex. \:\) I like to keep it simple and usually lump audio irregularities into either of two broad categories, physical (ie FR) and time domains(ie phase). Yes most can be expressed as functions of the other but for purposes of a discussion of equalization and acoustics its hard to correct one without damaging the other. That's why after a point applying more equalization to get the flattest FR curve actually sounds worse since phase anomalies are increasingly audible.

Those Audessey programs not only mess up phase but they also don't provide the smoothest response. In fact most of the time they make the 400hz and lower zone less linear. Behringer specifically warns about this in the literature accompanying their equalizers. Funny how Audessey never mentions it.

On your Axiom marketing conspiracy theory... ...just about every product these days has glitches, right? Not that makes it acceptable, but it does reinforce the importance of excellent service in whatever gear you buy these days.
Posted By: RickF Re: A1400-8 - 03/13/08 09:29 PM
Still in Sanibel John?
Posted By: Dundas Re: A1400-8 - 03/13/08 09:57 PM
 Originally Posted By: jakeman
I like to keep it simple and usually lump audio irregularities into either of two broad categories, physical (ie FR) and time domains(ie phase). Yes most can be expressed as functions of the other but for purposes of a discussion of equalization and acoustics its hard to correct one without damaging the other. That's why after a point applying more equalization to get the flattest FR curve actually sounds worse since phase anomalies are increasingly audible.

Those Audessey programs not only mess up phase but they also don't provide the smoothest response. In fact most of the time they make the 400hz and lower zone less linear. Behringer specifically warns about this in the literature accompanying their equalizers. Funny how Audessey never mentions it.


OK, I think we're pretty clear on your opinion on Audyssey (2 Ys 1 E). Now about the problem with the A1400-8 and whether I should buy one....
Posted By: jakeman Re: A1400-8 - 03/13/08 10:07 PM
I am Rick. I'll be here until Mar. 23. How far are you from Sanibel? It would be nice to get together.
Posted By: jakeman Re: A1400-8 - 03/13/08 10:12 PM
Only you can decide that one. Hamilton is only 3 hours from Dwight. If I was in your position, I'd take the drive, audition it and get the answers in person from the folks at Axiom also check out the alternatives. Having had the privilege of getting to know them over the last few years, I can tell you they are about as pleasant, honest and fine a group as I've met at any audio company. \:\)
Posted By: Mojo Re: A1400-8 - 03/13/08 10:37 PM
Yes, I see your point about frequency response vs. phase. Thanks!
Posted By: Dundas Re: A1400-8 - 03/14/08 12:50 AM
 Originally Posted By: jakeman
Hamilton is only 3 hours from Dwight.


Yea I know, 3rd generation family cottage on Lake Of Bays. I'd like to support the guys from Dwight.
Posted By: rmk1 Re: A1400-8 - 03/14/08 02:00 AM
 Originally Posted By: Dundas
 Originally Posted By: jakeman
Hamilton is only 3 hours from Dwight.


Yea I know, 3rd generation family cottage on Lake Of Bays. I'd like to support the guys from Dwight.


Outside of this potential Audyssey issue the A1400-8 is an amazing product. I am sure that Axiom will figure out what needs to be done and do it. The more I listen to this amp, the more I find to like.
Posted By: StuntGibbon TORTURE - 03/14/08 09:27 PM
The new definition of torture: A1400-8 arrived! Yay! But before the set of interconnect cables.... AHHHHHHHHHHHHH!

Impressions so far... it looks nice... it's large... and umm... heavy?
Posted By: EFalardeau Re: TORTURE - 03/14/08 09:48 PM
When are you expecting the cables? \:\)
Posted By: StuntGibbon Re: TORTURE - 03/14/08 09:51 PM
 Originally Posted By: EFalardeau
When are you expecting the cables? \:\)


Two days ago.
Posted By: rmk1 Re: TORTURE - 03/14/08 09:52 PM
Thats funny ... NOT

Are you using balanced (XLR's)? You could always run down to the nearest pro audio store and pick up some XLR mic cables. I used them for a while in a previous setup and they were cheap and perfectly functional.

The A1400 is heavy for it's size, no? I wish they would tone down the blue light.
Posted By: EFalardeau Re: TORTURE - 03/14/08 09:57 PM
I agree about the blue light. It's a bit bright.
Posted By: EFalardeau Re: TORTURE - 03/14/08 09:57 PM
So it must be your first child then! Apparently, the first one is always late!
Posted By: Ken.C Re: TORTURE - 03/14/08 10:03 PM
Not mine... he was 2 weeks early. That was a surprise.
Posted By: StuntGibbon Re: TORTURE - 03/14/08 10:03 PM
I'll be patient for the ones that are already on their way, since I already paid for them. (outlaw's just being a little pokey)
Posted By: JaimeG Re: A1400-8 - 03/14/08 11:03 PM
 Quote:
I hadn’t seen (Into the Wild) over the weekend. (BTW, Into the Wild is outstanding).


Indeed, I watched it last night, it was outstanding. Last year was a great year for movies, cant wait to se 'there will be blood'
Posted By: rmk1 Re: A1400-8 - 03/14/08 11:39 PM
 Originally Posted By: JaimeG
 Quote:
I hadn’t seen (Into the Wild) over the weekend. (BTW, Into the Wild is outstanding).


Indeed, I watched it last night, it was outstanding. Last year was a great year for movies, cant wait to se 'there will be blood'


I'm looking forward to that one myself.

I have No Country for Old Men in BR queued up for tonight.
Posted By: pmbuko Re: A1400-8 - 03/15/08 01:50 AM
We loved Into the Wild, as well.
Posted By: StuntGibbon Re: A1400-8 - 03/15/08 09:42 PM
Interconnects arrived this morning. Already all wired up. First test at a near reference level was some scenes from Ratatouille on BR. Easily already sounds better than any of our local theaters (tho, in their defense they have a LOT more space to fill with their sound.) (To recap this is the Onkyo 905 as a pre-amp, through the A1400-8, into the Epic 80/600 for 5.1)

Probably the most amazing thing to me so far is how clear and tight all the Foley effects come through. Breaking glass, especially, sounds really clear and in-your-face.
Posted By: fredk Re: A1400-8 - 03/15/08 10:01 PM
I'm jealous. I just finished listening to your setup (minus ep600) at Axiom on Monday and it does sound very very good.

Enjoy.
Posted By: EFalardeau Re: A1400-8 - 03/15/08 10:27 PM
Excellent! Ectasy without pills!
Posted By: EFalardeau Re: A1400-8 - 03/15/08 10:29 PM
BTW, if you want to get scared, tried the second DVD or Return of The King (the battle with all the Oliphants and the horses). That reaches extreme levels, but it does not feel "loud" with the 1400.
Posted By: jakewash Re: A1400-8 - 03/16/08 12:06 AM
Thanks for the tip Eric, I will try that with the SVS sub.
Posted By: haylo75 Re: A1400-8 - 03/16/08 01:23 AM
Congrats on your new amp, StuntGibbon! We all adjust to the sound of our home theatres, but I distinctly recall the astounding difference I heard when first experiencing my A1400-8. Listening to some of my favorite music was truly an emotional experience.
Posted By: StuntGibbon Re: A1400-8 - 03/16/08 02:57 AM
The best is when something truly surprises you. Like you're listening to a film at nice-to-the-neighbors levels, then nearly without warning you'll get something like a thunder crack or gun shot and the amp instantly throttles up and you're running to grab wall-hanging objects. (to the ep600's credit too, mind you)
Posted By: jakeman Re: A1400-8 - 03/18/08 12:54 AM
 Originally Posted By: Dundas
 Originally Posted By: jakeman
Hamilton is only 3 hours from Dwight.


Yea I know, 3rd generation family cottage on Lake Of Bays. I'd like to support the guys from Dwight.


Where on the Lake? I'm on Portage Bay.
Posted By: Dundas Re: A1400-8 - 03/18/08 03:59 AM
 Originally Posted By: jakeman

Where on the Lake? I'm on Portage Bay.


Baysville leg of the lake - Kerrimuir Road
Posted By: Kpt_Krunch Re: A1400-8 - 03/28/08 12:50 AM
 Originally Posted By: Ajax
Hi Kpt. You turn up in the strangest places. ;\)


LOL - how ya doing Jack? I actually have followed this forum for years. I never post here as I have never considered buying one of their products, until recently. This A1400-8 has really piqued my interest, and I will be doing a lot of research on it. This could be the amp I'm looking for for my h/t. We'll see \:\)
Posted By: EFalardeau Re: A1400-8 - 03/28/08 01:43 AM
It is an amazing product. I was a sceptic about separates (because of past experiences) before I got an A1400 in my place. I am now a complete convert.
Posted By: Kpt_Krunch Re: A1400-8 - 03/28/08 04:57 AM
 Originally Posted By: EFalardeau
It is an amazing product. I was a sceptic about separates (because of past experiences) before I got an A1400 in my place. I am now a complete convert.


I'll bet! This amp really really intrigues me. I'm still learning a lot about amplifiers in terms of how they work and how they can affect the sound. I like the 'technology' behind this amp. Except for this 'Audessey' thing which I don't really understand. I mean, I don't mean to piss anyone here off, but tell me, what real true 'audiophile' would EVER let a machine do a calibration for them? I always thought an 'audiophile' used their own ears and perhaps a ratshack meter (just to verify their own ears... as if they need to ;)) to get their sound just right. I know I've never used a built in program, just test tones, and since I'm not an audiophile, an analog ratshack SPL meter. Works great, easier on the amps too I guess \:\)

However, because of this 'flaw' shall we say, does that meant there is a problem with the design? I don't know, but if there is I'm sure the good folks at Axiom will resolve it a lot quicker than I can decide what amp to buy lol.

Right now, I'm debating between D-Sonic, Wyred for Sound, and the Axiom amps for D class amps. I'm not 100% I'm even going this route, but sound quality, size, power consumption (and delivery of course) are high on my priorty lists, and the D-Class amps seem to be the leaders for all three at their price points anyway.

Don't let this thread die folks. Keep posting your impressions/experiences with this amp. I'm all ears (so to speak) \:\)
Posted By: CV Re: A1400-8 - 03/28/08 05:11 AM
Unfortunately, I can't comment on other dedicated amps. My own experience has only been with receivers and then this Axiom amp. However, there was a noticeable difference going from my 90w/channel Onkyo receiver to the A1400-8. I would always get a lot of harshness in the sound at moderate to loud listening levels with certain material. I'm sure my receiver's amp was going into clipping. With the A1400-8, I don't hear that harshness. The difference, while remarkable on certain material, also comes at a huge price gap. In my case, I knew I was planning on having a much bigger home theater room in the future, so I bit the bullet and preordered it when there was a discount. I've been very happy with its performance, but again, I don't have a very meaningful point of reference, given my limited experience.
Posted By: jakeman Re: A1400-8 - 03/28/08 11:14 AM
I recently spent two weeks hanging around listening to music and watching movies at a friends place in Florida. After carefully considering his requirements last year I recommended he go with the following system: 3 VP150s, 4 QS8s, 2 EP500s, A-1400-8, Onkyo 885 pre-amp Denon TT, JVC-RS1 projector, Toshiba XA2 HDDVD, Dalite High Matte screen. A critical criteria was excellent sound reproduction and no blocking the views! All the speakers were mounted high and pointed down at the listeners. The subs were behind the piano and mid left sidewall.

He comes from a music oriented background, his father once being an opera singer with the Boston SO, and his mother an accomplished pianist. We listened mostly to piano, classical and jazz with high dynamic range. When his mother played piano unknown to us, it was hard to differentiate whether or not the system was playing . Sounds are very lifelike and realistic, so much so that both he and his mother say its the best reproduction of music and piano they have heard. Movie sounds confused his kids and pets especially when there were ringing phones or barking on the screen. There is great synergy between the equipment and the room. At the heart of it is the a-1400-8 which is lying on its side in the cabinet below left. Even at high levels there was no evidence of distortion.








Posted By: mapatton Re: A1400-8 - 03/28/08 09:32 PM
I see 4 remotes sitting there. Those need to be consolidated. \:\)
Posted By: Dundas Re: A1400-8 - 03/28/08 10:50 PM
Kind of screws up the amps cooling to sit it on its side that way. My A1400-8 arrived yesterday.
Posted By: jakeman Re: A1400-8 - 03/28/08 10:54 PM
How do you figure? Firstly the amp doesn't get hot. Secondly if it did there is more heat transfer with the amp on its side. He keeps it that way because of the internal dimensions of the cabinet.
Posted By: Mojo Re: A1400-8 - 03/28/08 11:42 PM
Two 150s are for left and right and one for centre, right?

That's a wonderful room. And it's not treated either.
Posted By: jakeman Re: A1400-8 - 03/29/08 12:03 AM
Yes it is a wonderful room with surprisingly good acoustics. Its not exactly without treatments since the wooden slats on the peaked ceiling effectively act as diffusers. I suppose it has a lot to do with the large airy dimensions (40 ft x 20ft x 15ft) and the fact that the speakers are up high pointed down. The 3 vp150s work very well much to my other surprise.

Initially I had thought m3s or m22s but the horizontal mains seemed to work best with the high placement. Also the a-1400-8 really makes them reach their full potential. The black couch is some 20ft away so the more powerful amp really delivers when dynamic range is needed. No audessey equalization necessary with that Onkyo though he is very much against such things anyway.
Posted By: ihifi Re: A1400-8 - 03/29/08 01:02 AM
Your friend is probably the only owner of the A1400-8 using it sideways. It will not get hot; perhaps little warm if he keeps the cabinet doors closed.

Three VP-150s across the top is very interesting; talk about matching the center to the mains. Unless the screen is retractable, one more center below the screen would be ideal. I also read somewhere that the A1400-8 runs cooler if all channels are connected.

With all this recent talk and setups with dual/multiple subs, I am finding myself increasingly motivated toward a second EP-500.

Thanks for the pics, John.

John
Posted By: Dundas Re: A1400-8 - 03/29/08 01:42 AM
 Originally Posted By: jakeman
How do you figure? Firstly the amp doesn't get hot. Secondly if it did there is more heat transfer with the amp on its side. He keeps it that way because of the internal dimensions of the cabinet.


Amplifiers rely on convection cooling that is why the fins on their heat sinks are vertical not horizontal. Probably not a problem but I wouldn't do it. The amp was designed to be horizontal and draw cool air in through the openings in the bottom cover and expel the heated air through the top.
Andrew Marshal commented on some heat in his review but I won't have the time to find out for myself for a few days.
Posted By: Mojo Re: A1400-8 - 03/29/08 01:51 AM
It also has a fan and I don't know how the orientation may affect its mechanical behaviour.
Posted By: Dundas Re: A1400-8 - 03/29/08 01:58 AM
 Originally Posted By: jakeman
No audessey equalization he is very much against such things anyway.


Makes it sound like a religious conviction not informed opinion but each to his own.

btw, Dan D'Agostino is "very much against" class D amplifiers
Posted By: Mojo Re: A1400-8 - 03/29/08 02:04 AM
Because they have the potential of killing his business.
Posted By: Dundas Re: A1400-8 - 03/29/08 02:07 AM
 Originally Posted By: Mojo
Because they have the potential of killing his business.


Perhaps that's his motivation but I suspect that Krell could design and market successfully some very expensive class D amps if they had a mind to.
Posted By: Mojo Re: A1400-8 - 03/29/08 02:18 AM
That would send mixed messages to his market. Now if he decides to pack in Class A and declare Class D the supreme grand champion of amplifier topologies, that would be a different story \:\) .
Posted By: Kpt_Krunch Re: A1400-8 - 03/29/08 02:25 AM
 Originally Posted By: CV
Unfortunately, I can't comment on other dedicated amps. My own experience has only been with receivers and then this Axiom amp. However, there was a noticeable difference going from my 90w/channel Onkyo receiver to the A1400-8. I would always get a lot of harshness in the sound at moderate to loud listening levels with certain material. I'm sure my receiver's amp was going into clipping. With the A1400-8, I don't hear that harshness. The difference, while remarkable on certain material, also comes at a huge price gap. In my case, I knew I was planning on having a much bigger home theater room in the future, so I bit the bullet and preordered it when there was a discount. I've been very happy with its performance, but again, I don't have a very meaningful point of reference, given my limited experience.


I'm sure there was. I should clarify a bit. I do know what an amp is, and I do have one (I have a 4 channel bridged to two channel HK PA2000 which provides 100 watts each to my Energy RC-70's). However, I want to go full out - a 7 channel amp. The PA2000 is taller than the A1400, and it is far more powerful.

My thing now is what is unique about an amp. Why does one amp 'sound' better than another. Sound is #1 on my priority list, with power second. Though I do know that if not enough power, then sound will not be there. I find my current PA 2000 runs out of steam at higher volume levels, things start getting a bit harsh (like what you described with you Onkyo). I must elaborate though - the volumes it starts to 'clip' are volumes I do not listen to normally as it is very loud. However, even at that volume, I expect and want more (when my son is a teenager, I don't want him wrecking my speakers..... or my amps :D).

I've got a year or so yet anyway before I buy.....unless there is a crazy sale or something \:D
Posted By: SirQuack Re: A1400-8 - 03/29/08 02:42 AM
"far more powerful" ?
Posted By: Ken.C Re: A1400-8 - 03/29/08 02:44 AM
Power hungry, I would bet..., either that or we're reading it backwards.
Posted By: Mojo Re: A1400-8 - 03/29/08 02:50 AM
How do you figure that the PA2000 is more powerful than the A1400?

If you are really worried about your son maxing out your system and destroying it due to clipping, then take the maximum rated power of your Energies, double it, and that's the amount of power you should look for in an amp.

As to what amp sounds the best, audible differences may arise from the distortion by-products. Some have more odd harmonic distortion components and others may have more even harmonic distortion components. Now as to whether or not these differences are audible, I don't know. I haven't spent any time doing any comparisons.

Remember too that the more sensitive the speaker, the louder it will sound with the same power input.
Posted By: Dundas Re: A1400-8 - 03/29/08 02:52 AM
 Originally Posted By: Mojo
That would send mixed messages to his market. Now if he decides to pack in Class A and declare Class D the supreme grand champion of amplifier topologies, that would be a different story \:\) .


He could market his class D line of amplifiers as his premium green line and spin some yarn about having all the advantages of class A but earth friendly and charge even more for them.
Posted By: jakewash Re: A1400-8 - 03/29/08 02:53 AM
 Originally Posted By: Kpt_Krunch

However, I want to go full out - a 7 channel amp. The PA2000 is taller than the A1400, and it is far more powerful.


Am I misreading this? you are saying your bridged H/K @ 100W/Ch is more powerfull than the A1400 @ 200W/ch?
Posted By: Mojo Re: A1400-8 - 03/29/08 02:54 AM
The A1400 is actually better than 200W/ch if used in only 2-channel mode.
Posted By: jakewash Re: A1400-8 - 03/29/08 02:55 AM
 Originally Posted By: Dundas

He could market his class D line of amplifiers as his premium green line and spin some yarn about having all the advantages of class A but earth friendly and charge even more for them.


Now that sounds like a true audiophile company.
Posted By: ihifi Re: A1400-8 - 03/29/08 02:58 AM
The A1400-8 actually pushes about one horsepower (745W) per channel in two-channel mode on a 15A supply and even higher on a 20A supply without clipping , distortion, compression, or heating up like a toaster. And, you can even put it sideways in a cabinet! \:\)

John
Posted By: jakewash Re: A1400-8 - 03/29/08 02:59 AM
 Originally Posted By: Mojo
The A1400 is actually better than 200W/ch if used in only 2-channel mode.
I know, I seem to remember 300W/ch in 2 channel and lets not forget the unique ability of all of its power into a single channel for a brief momment.

I was just going with the all channels driven idea as his H/K would be all channels driven since it is bridged;\)
Posted By: jakewash Re: A1400-8 - 03/29/08 03:02 AM
 Originally Posted By: ihifi
The A1400-8 actually pushes about one horsepower (745W) per channel in two-channel mode on a 15A supply and even higher on a 20A supply without clipping , distortion, compression, or heating up like a toaster. And, you can even put it sideways in a cabinet! \:\)

John
Not according to their own specs. 1 channel driven into 4 ohms would be 700W. I know they are being conservative.
Posted By: ihifi Re: A1400-8 - 03/29/08 03:04 AM
1 channel full and 6 channels at 1/8th power is also 700W into 4 ohms.
Posted By: jakeman Re: A1400-8 - 03/29/08 06:12 AM
 Originally Posted By: Dundas
Makes it sound like a religious conviction not informed opinion but each to his own.

btw, Dan D'Agostino is "very much against" class D amplifiers


He is quite informed about it and not alone in his views; he didn't need much encouragement from me on that one. The main problem with parametric equalization is that the filters introduce ringing and phase errors which can make sound audibly worse especially in the mid and high range. I use manual equalization sparingly and only in the bass regions where those side effects are less noticeable. Auto-equalization, like the current Audessey stuff, is an unfortunate bullet which rarely works well but does seem to have found a niche with people who aren't comfortable with manual adjustments or like the placebo effect they provide.

Dan D'Agostino designs wonderful Class A amps. I'm a big fan of Krell products. Five years ago I would have agreed with his views about Class D amps but todays designs are much different than what was available when he designed the Krells and easily challenge the best linear amps. Having read some of his comments, I'd say he is out of touch with developments in Class D and agree with Mojo that his comments are somewhat self serving. With the improvements in switching technology and the natural advantages of Class D in weight, size, cost and heat, its inevitable that the Class D amps will continue to displace Class As.
Posted By: jakeman Re: A1400-8 - 03/29/08 06:21 AM
 Originally Posted By: ihifi
The A1400-8 actually pushes about one horsepower (745W) per channel in two-channel mode on a 15A supply and even higher on a 20A supply without clipping , distortion, compression, or heating up like a toaster. And, you can even put it sideways in a cabinet! \:\)

John


Good point John. Like Jason said Axiom is being conservative with the specs. For people (like me) who have 20 amp circuits the Axiom amp should be renamed an A-2000-8. However any one channel is limited to 1440W by the protection circuit. If running all channels under the same loads, you should get close to 1000w in stereo mode or 633w in 3 channels, 500W into 4 channels etc. In reality most of the power will be dynamically allocated to whatever channel requires more.
Posted By: Kpt_Krunch Re: A1400-8 - 03/29/08 05:43 PM
 Originally Posted By: sirquack
"far more powerful" ?


Yep.... hehe, but I typed to fast .. I meant to say the PA2000 is taller than the A1400 but the A1400 is far more powerful (doesn't make much sense when you leave out "but the A1400".. sorry about that).
Posted By: Kpt_Krunch Re: A1400-8 - 03/29/08 05:48 PM
 Originally Posted By: jakewash
 Originally Posted By: Kpt_Krunch

However, I want to go full out - a 7 channel amp. The PA2000 is taller than the A1400, and it is far more powerful.


Am I misreading this? you are saying your bridged H/K @ 100W/Ch is more powerfull than the A1400 @ 200W/ch?


Nope, that's exactly what I wrote. I mis-typed it. So much for me knowing 'a littl bit' about amps LOL. As you see from my corrected post - that is what I meant to say (and did say,in my head, my fingers got a little ahead though and forgot to type that part in).

That's why I'm so interested. Here you got an amp that is not only smaller, but offers 8 channels of amplification, and is far more powerful, then my bridge PA2000 (hope that reads better lol).

Like I mentioned though, the big thing now is sound quality. From what I've read so far, that should also be a big improvement (not that H/K sounds bad).
Posted By: jakewash Re: A1400-8 - 03/29/08 08:04 PM
I think the sound quality is probably about the same as long as you are with in the useable range of the amp. However, those with the A1400 say it does have better attack/reaction, better low notes etc. to the music than the other amps/receivers they have used, even at low volumes, which makes me really want to hear one, I keep waiting for Mojo to buy one so I can have a listen. ;\)
Posted By: Mojo Re: A1400-8 - 03/29/08 08:24 PM
Mojo will never buy one if he keeps spending his time on these boards instead of making a buck.
Posted By: jakeman Re: A1400-8 - 03/29/08 08:25 PM
 Originally Posted By: jakewash
However, those with the A1400 say it does have better attack/reaction, better low notes etc. to the music than the other amps/receivers they have used, even at low volumes, which makes me really want to hear one, I keep waiting for Mojo to buy one so I can have a listen. ;\)


That summarizes it well. ;\)
Posted By: fredk Re: A1400-8 - 03/29/08 09:24 PM
 Quote:
...say it does have better attack/reaction
= slew rate?
This is how Tom Cumberland summed up the A1400. Tons of power + better slew rate/speed = better amp.

When I asked how much power the M80s need, Debbie gave the usual "any 100wamp will do" answer. Tom didn't miss a beat... "A kilowatt."

It took a bit of browbeating by Debbie to get Tom to admit you could drive the M80s with a 100w amp, but he really believes you need a lot more power to get the best out of them. The exchange was quite entertaining.
Posted By: Mojo Re: A1400-8 - 03/29/08 09:34 PM
So he must really be laughing at my half watt \:\) .
Posted By: jakewash Re: A1400-8 - 03/29/08 10:16 PM
Well, my 130W Denon does a great job at running the M80s to loud levels and certainly sounds as great as any amp I have heard. Now an A/B comparison is truly where you will be able to hear and notice the differences when present.
Posted By: Mojo Re: A1400-8 - 03/29/08 10:25 PM
I just think that Axiom needs to build more efficient speakers. For every watt that goes into a speaker, 99% gets converted to heat. We didn't all buy heaters...we bought speakers \:D .
Posted By: Spoiler Re: A1400-8 - 03/29/08 11:37 PM
 Quote:
Well, my 130W Denon does a great job at running the M80s to loud levels and certainly sounds as great as any amp I have heard. Now an A/B comparison is truly where you will be able to hear and notice the differences when present.


Ah, and there's the rub. No one as of yet has attempted an even semi-scientific comparison. All I've read so far from new owners regarding comparisons is "There's no need". I can understand how they feel after firing up the new amp, but I personally need more than that. That's why I'm eagerly awaiting Mojo's picking one up so I can get the real poop! \:\)
Posted By: Mojo Re: A1400-8 - 03/30/08 12:17 AM
So I've become the authority? Oh boy! Time to start charging \:D .
Posted By: jakewash Re: A1400-8 - 03/30/08 12:32 AM
Exactly, the kids can make their own clothes and you have a steady supply of protein or so it sounds from the other thread. What are you waiting for? Charge It! Wilma and Betty would be proud!
Posted By: jakeman Re: A1400-8 - 03/30/08 01:04 AM
 Originally Posted By: Spoiler

Ah, and there's the rub. No one as of yet has attempted an even semi-scientific comparison. All I've read so far from new owners regarding comparisons is "There's no need". I can understand how they feel after firing up the new amp, but I personally need more than that. That's why I'm eagerly awaiting Mojo's picking one up so I can get the real poop! \:\)




This may not be as scientific as you want but there are numerous side by side and listening comparisons with several other amps over a long period. At the end of the day voltmetres and graphs will only take you so far. \:\)

http://www.axiomaudio.com/boards/ubbthreads.php?ubb=showflat&Number=188805&fpart=1
Posted By: jakeman Re: A1400-8 - 03/30/08 01:11 AM
 Quote:
When I asked how much power the M80s need, Debbie gave the usual "any 100wamp will do" answer. Tom didn't miss a beat... "A kilowatt."

It took a bit of browbeating by Debbie to get Tom to admit you could drive the M80s with a 100w amp, but he really believes you need a lot more power to get the best out of them. The exchange was quite entertaining.





That's funny. Well they are both right, aren't they. Much depends on how far away you, type of music, and how loud you want to listen.

Disregarding other factors influencing amp performance, going back to that useful Allegro power calculator if you want 6db of headroom for dynamic range for the M80s in room and sit at no more than 2.8 metres you are good to go with 100w. You sit any further away, more watts please.

http://allegro-sound.com/Power.html
Posted By: tomtuttle Re: A1400-8 - 03/30/08 03:49 AM
 Quote:
So I've become the authority?


I think if you'll read carefully, you've been anointed as a dispenser of "real poop".
Posted By: CV Re: A1400-8 - 03/30/08 03:52 AM
Who's the toilet paper?
Posted By: St_PatGuy Re: A1400-8 - 03/30/08 05:57 AM
 Originally Posted By: CV
Who's the toilet paper?


I think that's us.



I've gotta go take another shower. . .
Posted By: CV Re: A1400-8 - 03/30/08 05:58 AM
I'm thinking maybe we should start buying into audio voodoo. Fake poop is so much easier to wash off.
Posted By: St_PatGuy Re: A1400-8 - 03/30/08 06:00 AM
Fake poop can fit in your pocket, too. . .


Never know when it might come in handy.
Posted By: CV Re: A1400-8 - 03/30/08 06:10 AM
Oh, man, if only I'd had some for Regina to sign.
Posted By: JohnK Re: A1400-8 - 03/30/08 06:56 AM
Joe, you're of course correct: overenthusiastic reports by users of audio equipment shouldn't be taken seriously, especially when they fly in the face of well-established principles of audio technology. The story is still the same: flat frequency response along with inaudibly low noise and distortion equal audibly transparent amplification, and this is true regardless of whether the amplifier is in a $300 receiver or is a $30,000 separate unit. Again, The Audio Critic puts it well in "Electronic Signal Paths Do Not Have a Personality" . Claims to the contrary have failed when put to the(properly controlled blind listening)test and manufacturers don't want to be made to look silly by claiming mysterious qualities that no amplifier can have.
Posted By: fredk Re: A1400-8 - 03/30/08 01:12 PM
 Quote:
That's funny. Well they are both right, aren't they

Yep and Yep, though you have to think a little to realize they are both right. I think that 100w is right on the hairy edge for minimum power. I understand why Denon and the likes are so popular here.

If you are in a bigger an like to listen to classical loud I can see the attraction of an amp like the A1400.
Posted By: jakeman Re: A1400-8 - 03/30/08 01:42 PM
Yes for any kind of well recorded classical or jazz at moderate volumes in anything but a small room a 100w receiver amp would guarantee you clipping at peaks and transients. Many people often mistake the sound of clipping distortion with "loudness" and rush to turn down their gear. Without clipping distortion higher SPLs don't sound so loud. That's often the first thing people notice when getting a more powerful separate amp. Other nuances like greater bass control or more textured sound usually follow. Doing a side by side comparison with different recordings and at varying volumes can be very revealing.

Denon makes a good product and it's true that the tradeoffs inherent in an integrated box are getting better but the quest for less compromised sound quality usually leads people to separates. Once someone goes that route they hardly ever buy receivers again. Over a longer time period, I've always believed its better value to go with an amp and upgrade the processor occasionally.
Posted By: jakeman Re: A1400-8 - 03/30/08 01:52 PM
 Originally Posted By: JohnK
Joe, you're of course correct: overenthusiastic reports by users of audio equipment shouldn't be taken seriously, especially when they fly in the face of well-established principles of audio technology. The story is still the same: flat frequency response along with inaudibly low noise and distortion equal audibly transparent amplification, and this is true regardless of whether the amplifier is in a $300 receiver or is a $30,000 separate unit. Again, The Audio Critic puts it well in "Electronic Signal Paths Do Not Have a Personality" . Claims to the contrary have failed when put to the(properly controlled blind listening)test and manufacturers don't want to be made to look silly by claiming mysterious qualities that no amplifier can have.


I guess its safe to say you won't be debating the merits of Class A and D amps with us anytime soon.
Posted By: MarkSJohnson Re: A1400-8 - 03/30/08 02:08 PM
 Originally Posted By: Mojo
So he must really be laughing at my half watt \:\) .


We ALL are, Mojo...we ALL are.....
Posted By: Mojo Re: A1400-8 - 03/30/08 02:57 PM
Just to add add to the conversation above, I find that I cannot listen to well-recorded classical pieces on my system due to my meager 90W/channel. I find I have to turn my Denon's gain knob to -3 (in order to properly hear the piccolos, oboes and the like) when I normally listen to -20 or -25 for rock, blues, jazz, etc. Then of course when there's a loud passage like brass and drums, it sounds terrible. My wife keeps saying that that's what the woodwinds should sound like and I shouldn't be turning it up to hear them "better".

I also find that out of the dozens and dozens of classical CDs that I've listened to as a result of recommendations from Johnk and others on this site, almost all have sounded flat and lifeless.

I'm not convinced that my second problem is amp-related because I have two in particular that sound absolutely fantastic. So I'm blaming the sound engineering for all others. As for my first problem, it's definitely the amp. When I crank it up that much, I run out of headroom.

And you may laugh at my half watt, but I boast a whopping 22.6dB of headroom \:\) .
Posted By: jakeman Re: A1400-8 - 03/30/08 03:42 PM
One of the most elegant stereo systems I have heard recently was at a friends place in January who uses a 5W single ended triode tube amp to drive a pair of high sensitivity (95db/w) Cain & Cain Abby speakers. He listens mainly to classical and jazz and they are very detailed and transparent in his small apartment. The downside was not good deep bass performance below 75hz. Otherwise it sounded very nice for strings and vocals in particular.
Posted By: mapatton Re: A1400-8 - 03/30/08 11:34 PM
Dynamic range over what? My favorable listening is at 92db (at 1 meter). And I would desire more than 6 db dynamic. More like 25db \:\)
Posted By: Dundas Re: A1400-8 - 04/07/08 05:28 AM
 Originally Posted By: jakeman
Firstly the amp doesn't get hot.


I guess hot is a relative term. The thermometer I have set on top of the amp is reading 43C after running for several hours at low volume on an open (no top no sides) peg board (holes) shelf.

It feels hot to me!
Posted By: EFalardeau Re: A1400-8 - 04/07/08 09:48 AM
 Originally Posted By: Dundas
I guess hot is a relative term. The thermometer I have set on top of the amp is reading 43C after running for several hours at low volume on an open (no top no sides) peg board (holes) shelf.

It feels hot to me!

Yes hot is relative. And relatives like company!
To complete your post, it would be nice if you ran some comparisons (one at high volume would be nice), but also compare it to the temp of your computer, your DVD player idle/playing and so on...
Thanks in advance.
Posted By: jakeman Re: A1400-8 - 04/07/08 02:24 PM
 Originally Posted By: Dundas

I guess hot is a relative term. The thermometer I have set on top of the amp is reading 43C after running for several hours at low volume on an open (no top no sides) peg board (holes) shelf.

It feels hot to me!


Right, like Eric says hot is relative. If you want to compare the meaning of "hot" try the same test with Class A, AB, tube or any other amp. Its the reason why Class D amps are now finding their way into heat sensitive applications such as integrated digital streaming devices or music servers.
Posted By: rmk1 Re: A1400-8 - 04/07/08 04:57 PM
I found the A1400-8 ran warm as well but I did not put a temp guage on it. I am now running a Sunfire TG7400 and it runs noticably cooler (based upon touching the case) during use.

BTW, I returned the A-1400-8. I found the two amps very close in performance but I slightly preferred the sound and flexibility of the Sunfire especially the signal sensing "Auto On" feature. I could never get the 12 Volt trigger feature of the A1400-8 to work with my Integra. As a result was I was leaving the amp on all of the time and it was very warm even at idle. I also use and like the Sunfire's Current/Voltage Source output options for my main speakers.

Again, I liked both amps a lot but I have a history with Sunfire amps and for me the A1400-8 needed to be noticeably better ... and it just wasn't.

Posted By: jakeman Re: A1400-8 - 04/07/08 05:21 PM
Must be a fine amp Rob. What's the purpose of Sunfire's Current/Voltage Source output options?
Posted By: rmk1 Re: A1400-8 - 04/07/08 06:11 PM
 Originally Posted By: jakeman
Must be a fine amp Rob. What's the purpose of Sunfire's Current/Voltage Source output options?


Hi John,

Yes the Sunfire's are nice amps but i don't think you will like the explanation . According to a whitepaper by Bob Carver, you can create a "Tube Amp" sound by increasing the impedance of the speaker outputs "Current Source" (as I recall they use a 1 Ohm resistor). They suggest bi-wiring the speakers with the Current Source to the Tweeter ("warmer sound") and the Voltage Source to the bass/mid drivers.

I have played around with this a bit and currently use the above config with my Revel Studios. The differences are slight but the concept is interesting. It is easily bypassed by running from the Voltage Source outputs only. Here is a link to the Sunfire Whitepaper
Posted By: EFalardeau Re: A1400-8 - 04/07/08 06:15 PM
I first had trouble with 12V trigger and my Onkyo 805 until I realized that it may not necessarily work with a stereo jack. I switched to mono and it started to work just fine. Were you using a mono or stereo 1/8 cable?
Posted By: rmk1 Re: A1400-8 - 04/07/08 06:22 PM
 Originally Posted By: EFalardeau
I first had trouble with 12V trigger and my Onkyo 805 until I realized that it may not necessarily work with a stereo jack. I switched to mono and it started to work just fine. Were you using a mono or stereo 1/8 cable?


Yes, I tried two different mono 1/8" cables and double checked the settings in the Integra. No response on the A1400-8 side . I have not tried this feature with the Sunfire (even though it has it) as I prefer the signal sensing "Auto On" feature. Works great and one less cable to mess with.
Posted By: jakeman Re: A1400-8 - 04/07/08 07:14 PM
Interesting feature. I read that paper, Rob, and like his technique for making the amp more heat efficient. On the other hand, I doubt that impedance change will get you "tube" sound in the mid and high drivers. Perhaps this impedance/voltage thingee is there to appeal to tube fans. Many designers over the years have tried to come up with topologies that get the best of transistors and tubes. I'm glad Carver doesn't use tubes in a hybrid amp design. In any event, it looks like a very robust and beefy amp, one that will be hard to clip and should provide high quality amplification and sound .

The only way I know to successfully achieve the "tube" sound Carver is suggesting in his paper is by dedicating a formidable tube amp to drive the mid/highs and a separate SS amp connected to the woofers. If you can get the gains matched and the amps are close enough in phase, the presentation can be superb. I've employed such a setup with a McIntosh MC2102 and a Bryston 4BSST.

On another note, I was at the Montreal Audio Show this weekend and there were hybrid tube/SS amps on display at stratospheric prices which didn't sound good compared to dedicated SS or tube amp setups. Such hybrid amps are notoriously unstable. I once had a 300w Moscode tube/SS hybrid amp which fried my mid and high drivers.
Posted By: Dundas Re: A1400-8 - 04/07/08 10:33 PM
 Originally Posted By: EFalardeau

Yes hot is relative. And relatives like company!
To complete your post, it would be nice if you ran some comparisons (one at high volume would be nice), but also compare it to the temp of your computer, your DVD player idle/playing and so on...
Thanks in advance.


OK, I left the amp running for about 9 hours with the volume on the preamp (a Denon AVR-3806) turned all the way down.
The amp’s temp was 44C.
The Denon’s temp was 35C and my Motorola DCT 6412 DVR, which is always left on, was 36C. Both the receiver and the cable box are in a unit that is closed top, bottom and sides.
Room temp was 21C

The A1400-8’s manual states:
“Precautions: Air flow in the bottom vents and out the top vents of your A1400-8 is very important. Do not block these vents in anyway. Your A1400-8 is designed to operate in ambient temperatures up to 30 degrees C (86F). Since the A1400-8 will actually cool down as you increase the output please be sure to turn off your amplifier in very high ambient temperature conditions when not in use.”

Andrew Marshall in his Audio Ideas Guide review suggests connecting the input of the typically unused 8th channel to a signal source. Would be nice to hear what Axiom recommends.
Posted By: rmk1 Re: A1400-8 - 04/07/08 10:36 PM
 Originally Posted By: jakeman
Interesting feature. I read that paper, Rob, and like his technique for making the amp more heat efficient. On the other hand, I doubt that impedance change will get you "tube" sound in the mid and high drivers. Perhaps this impedance/voltage thingee is there to appeal to tube fans. Many designers over the years have tried to come up with topologies that get the best of transistors and tubes. I'm glad Carver doesn't use tubes in a hybrid amp design. In any event, it looks like a very robust and beefy amp, one that will be hard to clip and should provide high quality amplification and sound .

The only way I know to successfully achieve the "tube" sound Carver is suggesting in his paper is by dedicating a formidable tube amp to drive the mid/highs and a separate SS amp connected to the woofers. If you can get the gains matched and the amps are close enough in phase, the presentation can be superb. I've employed such a setup with a McIntosh MC2102 and a Bryston 4BSST.

On another note, I was at the Montreal Audio Show this weekend and there were hybrid tube/SS amps on display at stratospheric prices which didn't sound good compared to dedicated SS or tube amp setups. Such hybrid amps are notoriously unstable. I once had a 300w Moscode tube/SS hybrid amp which fried my mid and high drivers.


You always have an interesting take on things John, thanks. I have no base line for a Tube vs. SS amp comparison so the slight changes I notice with Sunfire’s Current Source outputs may well be imagined. I did feel that the Sunfire was just as powerful but a bit less bright sounding but again, that observation is subjective at best. I know Axiom has a winner with this amp and I’m glad I had a chance to run one in my system.
Posted By: jsw Re: A1400-8 - 04/08/08 02:42 AM

Does anyone know how this amp the 1400 sounds ,compare to say the outlaw 7900 300x7 amp?
Posted By: Dundas Re: A1400-8 - 04/08/08 03:33 AM
 Originally Posted By: jsw

Does anyone know how this amp the 1400 sounds ,compare to say the outlaw 7900 300x7 amp?


Below clipping level - the same.
The Axiom is about 90 lbs. lighter and does not require 2 separate AC power circuits.
Posted By: SirQuack Re: A1400-8 - 04/08/08 03:48 PM
Plus the outlaw is not a digital amp.
Posted By: tomtuttle Re: A1400-8 - 04/08/08 04:39 PM
Plus, it's not going to dynamically deliver higher output. I don't know about you guys, but I seriously doubt that I need 300 watts for the surrounds. The Axiom amp is unique in its ability to dump it's entire capability into whatever channels need it.
Posted By: SirQuack Re: A1400-8 - 04/08/08 07:19 PM
yup like my m80's. \:\) , oh wait, I don't have the amp, \:\(
Posted By: EFalardeau Re: A1400-8 - 04/08/08 07:59 PM
Slew rate of that 7x300 is also only 50V (compared to +80V for A1400). Micro-dynamics and accuracy would thus be less impressive than the A1400. 50V is not bad per se, but for the same price or so, the difference is almost a no brainer (at least for me or classical music listener in general).
Posted By: tomtuttle Re: A1400-8 - 04/08/08 08:59 PM
And don't forget about the long-term savings in energy costs. \:\)
Posted By: EFalardeau Re: A1400-8 - 04/08/08 09:06 PM
Yes! Go Green without have to turn down the volume! \:\)
Posted By: Dundas Re: A1400-8 - 04/09/08 12:13 AM
 Originally Posted By: sirquack
Plus the outlaw is not a digital amp.


Is the Axiom? The A1400-8 is a Class D amp. The "D" does not stand for digital.
Posted By: EFalardeau Re: A1400-8 - 04/09/08 12:17 AM
A1400-8 is a digital amp. Check the front page of your manual! \:\)
Posted By: Ken.C Re: A1400-8 - 04/09/08 02:57 AM
D does in fact stand for digital.
Posted By: JohnK Re: A1400-8 - 04/09/08 03:18 AM
Nope; D just happens to be the amplifier class that follows class C. It's a switching amplifier(possibly even tube-powered) that can use either analog or digital control circuits and of course has an analog output. See brief Wiki discussion.
Posted By: jakeman Re: A1400-8 - 04/09/08 03:22 AM
In the general nomenclature of amps, D was just the letter that came after C to designate the class of amps that converts an input into a pulse-width modulated analog signal. It was not meant to refer to digital amps.

Digital amps convert input into a pulse-code modulated signal. Digital amps can be Class D, Class E or Class F if they pulse code modulate.
Posted By: SirQuack Re: A1400-8 - 04/09/08 03:40 AM
Dundas, yes the Axiom amp is a digital amp, the "D" has nothing to do with it.
Posted By: Ken.C Re: A1400-8 - 04/09/08 03:55 PM
Oh fine.
Posted By: fredk Re: A1400-8 - 04/09/08 10:11 PM
... also stands for Doh!


Posted By: Mojo Re: A1400-8 - 04/10/08 12:44 AM
There's no such thing as a digital amp as there's no bit-stream conversion at all.
Posted By: SirQuack Re: A1400-8 - 04/10/08 12:45 AM
So why does Axiom and others call their amps a digital design?
Posted By: Mojo Re: A1400-8 - 04/10/08 12:52 AM
Good question. I don't know the history of that one. Maybe it has to do with the fact that the FETs turn on and off really fast so for slang they call it "digital".
Posted By: Mojo Re: A1400-8 - 04/10/08 12:56 AM
The A1400's efficiency is proportional to the power sourced from it. So for me playing at a half watt, it's probably as efficient as a lightbulb \:\) .
Posted By: Murph Re: A1400-8 - 04/10/08 11:08 AM
I didn't think light bulbs were all that efficient. They shed a lot of heat.

Sorry, I have no real point here. When I'm overtired my brain woks in odd ways.
Posted By: Mojo Re: A1400-8 - 04/10/08 02:03 PM
That's right Murph. I don't know how efficient a lighbulb is exactly but it's probably less than 10%.
Posted By: gmeyer Re: A1400-8 - 04/10/08 05:52 PM
Not sure if the amp utilizes this or not but I think it explains where the digital in Pule width modulation comes from

http://www.embedded.com/story/OEG20010821S0096
Posted By: gmeyer Re: A1400-8 - 04/10/08 05:57 PM
also found this really technical guide to the Basics of class D amplifiers

http://www.irf.com/technical-info/appnotes/an-1071.pdf
Posted By: JohnK Re: A1400-8 - 04/11/08 03:19 AM
The International Rectifier discussion is excellent, but the embedded link doesn't use the term "digital" in the generally accepted manner, and some might say is simply incorrect. Pulse Width Modulation of a continuous analog waveform doesn't involve any digital sampling, and although the max/min appearance of the PWM waveform has been said to be "digital-like" in appearance, it's still just a modulated continuous analog waveform. The analog waveform "concealed" within the PWM waveform is revealed when the low-pass filter removes the PWM frequency and its harmonics, leaving the original analog waveform.
Posted By: Mojo Re: A1400-8 - 04/11/08 04:37 AM
Yeah, that's right. I think some marketeer called this "digital" to be "hip" with the times. That's the difference between architecture and marchitecture \:\) .
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