Due to work commitments, I've been away from home for most of the last year. Christmas came, my wife bought me a nice new TV :), I've got time on my hands again and I've had a chance to watch some movies and spend a lot of time listening to music. And somethings been missing...

Although I probably should have realized it was the sub, I was getting some LFE during movies so it didn't initially jump into my head.

My initial thoughts were that one of the kids may have adjusted the setup (although they do know better) but everything was as I left it.

I went through my setup from the beginning again.
- sub crossover to 120Hz
- receiver crossover to 80Hz
- sub volume to 10 o'clock to start
- sub in phase
- all speakers set to small

At 10 o'clock I get nothing, and the sub won't even wake up on its own. By 2 o'clock I start to get the really big LFE effects, but even at max volume, I don't get any bass other than the LFE channel on DVD and nothing off CD.

From there, I worked back to the amp. I checked continuity on my sub cable which seems fine. I changed my sub cable out with another 75ohm cable I had on hand. I checked the sub preamp out on the receiver with my voltmeter and I do register a signal.

My next move was to bypass the receiver altogether and feed the CD player directly to the sub input. Nothing.

Is my subwoofer amp hooped?

Am I completely missing something?

Is there something else I can check?

Thanks.

endish,

Have you checked the SW receiver trim level on your Yamaha. This setting could have been turned down which could lead to low output and also lead to the auto/on not being able trigger. What level is that set to on your Yamaha.

Good luck!

The SW trim level seems fine. It's currently set 3 ticks above 0, which is higher than any of the speakers which vary from -1 to 2.

120Hz is the max crossover for the sub, so that should be out of the picture.

Try boosting the level on the reciever a tad more and see if that helps at all.

Endish, I've been hesitating in replying until I could think of something sensible, but decided to reply anyway. As Dr.Horse suggested, temporarily set the sub trim on the receiver all the way up to see if that "wakes up" the sub amp.

One puzzling thing is the failure with the CD player direct to the sub. That would seem to indicate that the amp was shot, but you say that some LFE was experienced from the sub during movies, so the amplifier has some life, but seems to require an unusually high voltage input(higher than the CD player could provide)to turn on.

*giggle*

Have you tried unplugging the sub from the outlet and letting it sit for a bit before you plug it back in, a year is a long time.

I haven't, but what might that accomplish?

I will try bumping the level tomorrow. I missed the kids' bedtime limit for tonight

It'll recalibrate the phased flux capacitor to the inverted tachyon field array.

Sometimes electronics just need a reboot. Granted, there's not much in a sub that ought to require a reboot, but it's worth a shot. Something easy to try, anyway.

I can think of a couple of other ideas.

1) Turn the sub's crossover all the way up, as high as it will go. To 'bypass' if that's an option. You want the receiver doing the crossover duties, not the sub.

2) Double check all of your connections & wiring. Make sure your sub cable isn't falling out somewhere or has a break in it. I'd physically disconnect & reconnect every cable in the chain. But since you're seeing voltage with the voltmeter, I don't know - sounds like you're all good on the connections front. Perhaps double check the connections & switches on the sub itself. Is there an auto-turn on setting? Perhaps jiggling that switch a bit might help. If the switch has an 'On' position, try that instead of 'Auto'. See if that makes any difference.

3) Have you tried calibrating your system with an SPL meter? It may not solve the problem, but it would give you some idea of how many DB 'cold' the sub is compared to the rest of your speakers. I don't know anything about Yamaha receivers, but your description of the settings does sound like it ought to be working.

4) Make sure the receiver isn't in some 'midnight' mode, where it's attenuating the output.

5) If it won't cause you too much stress, as a last-ditch effort you could do a full reset on the receiver. Sometimes settings get messed up and it could be hard to diagnose what it is. Resetting it would let you start from scratch. Yes, you'd have to set it all up again, potentially a PITA. I'm not very optimistic that this would solve anything, but it's something.

But again, since the sub didn't work with the CD player, that would almost have to indicate that the problem is in the Sub. Would a CD player provide enough output voltage to trigger a sub? I don't know. Anyone?

Good luck.

A cd player should work with the sub, Alan has mentioned doing this to check a sub before. The rest of you have pretty much covered it, well done. My first thought was as Peter mentioned some sort of dynamic compression is being used on the yamaha to keep the range low which would explain only the most extreme LFE making it to the sub.

I would also suggest calling Axiom to see what they say and any possible help/suggestions they may have, you may find a new amp on its way and the problem solved by this weekend.

I suggest you pull the amp off the back to see if one of the cables is loose
Mel N.

+1 Did I miss another good thread? You never know when stuff takes a left turn around here.

Well this one is into the second page and still seems to be on track. Are you guys slipping?

My two test discs that I'm moving forward with are Pirates of the Caribbean 2 for DVD and Oscar Peter Jazz Essentials for CD. The DVD has lots of LFE and a deep soundtrack and the CD features Ray Brown with a lot of bass that goes down below a deep C (~65 Hz) so I'm sure that my source material is delivering the right content.

RE Sir Quack: I unplugged over night on the off change that something may reset, but this evening the difference in performance is not statistically significant (I'd say identical, but technically I can't back that up)

RE Dr. House: I bumped the subwoofer level all the way and I get output with the sub volume as low as 12 o'clock, but at 50%, that seems awfully high for the minimum threshold. It is certainly not consistent with past performance where the level was set at three ticks vice 10. I still do not believe I am getting all I should be off the CD.

RE Peter Chenoweth: I'm satisfied that the cables and connections are correct. I hadn't considered the night mode, but confirmed that is is not enabled. As Jakewash noted, Alan Loft has mentioned patching the CD player directly to the sub input in the past for fault finding purposes.

RE Onn: I pulled the amp and the internal connections are tight


I believe that the CD I've been using is my best source materiel for experimenting with. Knowing the music, my sense is this: My sub has two issues. First, there is an issue with the sub cross over setting or other LPF which is interfering with performance. Second, the is a gain issue such that typical/normal/reasonable levels are not being produced.

I will contact Axiom tomorrow, but I'm still ready to try anything else you can come up with.

Thanks for the support

A bad amp.

Thought I'd chime in here as well.
My EP350 volume is up @ 75% to get the proper depth in the low end. I had some of placement issues at first (as some of you know). I too felt as thou I wasn't getting the performance at that volume level, but JC @ axiom assured me 75% volume was totally normal.
I do have a large room as well. I still "kinda" feel like it should push more low end at that volume level (my yamaha trim is set to +2, XO at 80hz). I just don't have anything to compare it to in the same class as the EP350.

The thought of returning it (still within 30days) goes thru my head so I can try a different sub to compare, was thinking about the HSU MK3. Worst case is they both will perform about the same and I can always return the MK3 and reorder the EP350. Both are close to the same money, I would be surprised if the was a "huge" difference. If there was, I would suspect I too have an amp issue with my EP350.

It's a tough decision because I'm really not sure if it's even under performing or not. Some here tell me they have their 350 volume no where near my level & get plenty of low end.

BTW, when connecting a CD player to the sub, what exactly is that supposed to tell me? Should the sub be cranking @ 75% volume with a CD player? What am I listening for to tell me my Sub is performing normally?

Dana

I wouldn't be

Hhmmm...anyone else agree?

Never mind, I just read a few other posts & Craigs sub list, the will be a big difference for sure. The EP500 would be more of a fit against the MK3.

Dana

My setup is in my basement family room and the room isn't that big. In the order of 10x22x7 with a couple of bumps to break up the long walls. About 1400 sqft.

If I had to push the volume to 75% because that's what my room required, I'd be satisfied with that or move on to a different sub if I was concerned.

In my case, it's not a matter of not enough to fill the room at a given setting, it's that I'm getting nothing until I hit what I believe to be an unreasonable high lower threshold.

Actually, You do. Every single time someone posts a new thread...

Following my last post, I exchanged some email with Alan who asked me to check a couple of extra things.

1. How does the red/green led behave when a signal is introduced? Does the LED turn green (not always). But it always come green if I toggle the ONOFF switch

2. If I disconnect the sub cable from the sub and only insert the signal terminal while keeping the cable shield physically separated, do I get a hum/buzz? No


I heard back from Alan at 9 who recommended I talk to JC. I called JC at 1145 who already knew the issue and was waiting for my call. By the time I got back from lunch and checked my email, I had a notice from Noreen letting me know the new amp had already been shipped.

I love customer service. It's so rare to come across.

Wait until you see how they pack the replacement amps for shipping. It is quite impressive as well!

Jason

I know both of my Yamaha recievers have a screen that allows you to set the LFE/BASS output to FRONT, SUBWFR, or BOTH.

Did you check that screen? I think when Fronts are set to LARGE and LFE/BASS is set to SUBWFR, you will only get LFE to your sub not bass from 2 channel music. You need to set BOTH or have your Fronts set as SMALL.

Just my 1st thought, after I read your post. Set it to BOTH even if you dont want to keep it there, just till you get the sub working.

**I guess I didn't read far enough. Good luck with the new sub amp. :-)**

Shortly after Axiom shipped the new amp, I went away on vacation (Vegas, baby!) so I've only had a chance to deal with it in the past couple of days.

I arrived back home to find a nice big box in my front hall. I unpacked the amp and was happy/surprised to find that it is the newer version from the v3

The leads to the driver attach via a blade terminal on the new amp while my older amp connected via the standard screw connectors. After a quick discussion with JC at Axiom, the easiest way to deal with this was to cut off the terminal connectors from the leads, strip some housing and solder the strands to prevent any strays from making undesired connections.

With the amp now prepared, it was an easy matter to pop off the old one, connect the new amp to the driver and secure the amp onto the back of the cabinet.

I fired up some Red Hot Chili Peppers and the amp immediately came to life with the crossover set to max and the volume set to 9 o'clock. I've still got to spend some time fine tuning the amp and receiver settings but it appears that everything is back the way it should be.

Thanks to all who provided feedback and suggestions via the forum.

Thanks to Alan and JC at Axiom for quickly getting back to me and helping to sort this out.

Norm

Sounds like you are good to go now.

Hmmm..Successful Flea.

Good name for a band.

Good news!

Good news indeed! I love my EP350