Axiom Home Page Forums General Discussion Technical Questions subwoofer not working..i think im an idiot

So i hook up my epic midi 125 http://www.axiomaudio.com/epicmidi_125main.html with my denon 2105 http://www.usa.denon.com/ProductDetails/451.asp. I use a monster THX Digital Coax cable http://www.monstercable.com/thx/productPageTHX.asp?pin=1599&LastPage=Digital%20Interconnects. I plug the cable in the Line IN from the sub to the Subwoofer jack in the receiver. I get nothing from the subwoofer. The little green light is on indicating power, but i get 0 sound. Am i using the wrong cable?

In the menu of the 2105 under speaker set-up, do you have yes or on for the subwoofer?

yes it is..i should also point out that my surrounds and center dont work either. Im only getting sound from my 2 fronts.

how is your DVD player connected to your receiver?

i have not hooked up my dvd player yet. Right now just tryin the radio.

No problem, but you'll need to make sure you are using a mode which takes the stereo signal from the radio and expands it out to a 5 channel signal to make all the speakers work.

Something like Dolby Pro Logic II would do.

Alternatively, you could start at the speakers and work back. Look in the manual for test tones and push whatever buttons you need to get the test tones running. That will put a "shhh" pink noise signal out on one speaker at a time and let you verify that the speakers are all hooked up properly and the amplifier channels are all working.

EDIT -- if you haven't already read this article from Alan, it's worth a quick look. Bottom line is that the problems you are having are really common... a whole bunch of things have to be set correctly to get 5.1 out, and if ANY of them are wrong you're only gonna get stereo until you find the right setting.

http://www.axiomaudio.com/archives/dolbydigital.html

Just keep telling us what you did and we'll get you through it...

... or just give the Axiom folks a call in the morning, they deal with this all the time as well. Home theater is like any other "open system" -- sure you get to mix and match, but you also need a room full of geeks to get the mix & matched system to work

try a DVD. The radio is 2 channel stereo. I guess you could apply a DSP to it to make it play in your surround speakers, but it isn't going to play in your sub because there isn't really any low frequency sound in FM radio.

A DVD will have a 5.1 channel soundtrack. The "5" stands for your 5 speakers (Left, Right, Center, Surround Left, Surround Right) and the ".1" stands for the Low Frequency Effects (LFE), which your subwoofer will play.

Your subwoofer can also play sound from the main speakers depending on how you set things up. But start with getting everything hooked up correctly and working.

woohoo ok now the surrounds and center are working...works when i switch it to 5 channel or dolby, thanks!. But my sub still doesnt work..whats up with that...am i using the right cable...i noticed there are "subwoofer" cables from monster. am i suppose to use one of those?

There really is no such thing as a "subwoofer" cable. They just market them that way. Any RCA type connector running from the sub out to line in will work just fine.

The receivers have many settings on them that need to be set to correctly represent your system. Although most don't like it, one of the best things you can do is read and re-read your owners manuals and apply what you learn to your system. It took me numerous reads of my receiver manual to figure out what each setting meant and what it did.

Don't overlook the subwoofer manual as well.

Jonn, just about any cable with RCA connectors works fine. If you haven't already done so you should do what John Bridgman suggested: look in the 2105's manual for the section on calibrating with the test tones and see if the test noise comes through the sub when it's the sub's turn.

Let's check a couple of things re: the subwoofer :

1. Make sure the cable is going from "Sub Out" or "Subwoofer Out" on the receiver to "Line In" on the sub. If you are connected to "Line Out" it isn't going to work. You are getting a green power light so this is probably OK but check anyways.

2. Make sure the crossover is set all the way up, ie 120 Hz. You're not actually using the crossover in the sub; turning it to the highest frequency makes sure it won't filter out any frequencies.

3. Look in the speaker setup menu on your receiver and make sure all the speakers are set to "small". This will take the bass content from each channel and route it to the subwoofer, along with the "LFE track" or bass sound effects on the .1 channel. If your speakers are set to "large" then the sub will only get bass from the LFE track, which isn't always active on many DVDs.

4. Adjust the sub volume control on the back to maybe a quarter of the way up; play a DVD with 5.1 sound (an action film, no chick flicks ) and turn up the sub volume until you hear something...

What do you have the volume set on the back of the sub, a good rule is 10'o clock to 12'o clock position. Do you have the crossover set on your receiver? I have mine set to 80hz and all my speakers set to small. For CD's and radio music I listen in Direct mode. Also, if you click the round button on the remote while your listening, it will cycle through each channel, what sound level do you have the sub set at? Have you run the Auto Setup with the Mic on the Denon?

>>For CD's and radio music I listen in Direct mode.

Of course you have M60 mains, not M2s

I would still think with M2's you would use direct mode, as it shuts down other un-needed functions on the receiver to make a more pure sound. In Direct mode the sub still works, so I would think it would be the same for smaller speakers. As long as he has speakers set to small, and has his crossover set correctly, he should be good to go. He may have to bump up the crossover to 120hz or so since he is using bookshelfs.

I have to admit, I have never been able to fully understand exactly what Direct and Pure Direct modes do on a Denon.

The HK's are really simple -- you can turn the DSP off, but you lose bass management.

The Direct modes on Denon seem to drop out the tone controls but keep the DSP running unless you also turn off the sub. Seems to me, though, that if the bass management is still running (it's the DSP that filters the bass out of your main channels when running the speakers in Small) then you aren't really running what I would call Direct, are you ?

Or is the idea that the mains are getting a full-range signal bypassing the DSP, but the DSP is still running to peel off the LF information and send it to the sub ? If that were the case the sub info would still go through the DSP but your mains would get "pure direct signals"

Any ideas ? When you have the mains set to "small" and run in Pure Direct do you get deep bass out of the mains ? If not, what other than the DSP is... um... de-bassing the signal ?

EDIT - I have read the manual a few more times and am starting to suspect that Pure Direct is only different from Direct when the sub is turned off. The manual for the 2805 says a few times that "the Subwoofer channel must be set to Off in order to disable the digital circuits" or something like that. My guess is that the DSP keeps running as long as the sub is enabled.

Anyways, thread drift... back to getting this guy's sub running

ok i tried a whole bunch of stuff...receiver setup, testing with dvd..bla bla...still dead as a doornail. So i called axiom up and they had me run a few tests. They said run a dvd and plug one of the rca's into the sub..i got nothing. They also had me test the cable by licking the end while plugged into the sub...got nothing. They said it may be the cable...I went a bought another cable...still no sound with the new cable. Sooooo, they are shipping me a new sub. Thanks for the help...We will see what happens when i get the new sub...thanks again.

Very interesting, I can't wait to hear the results...

Jonn,"...test the cable by licking the end while plugged into the sub..."? Did they explain this?

Man, that just don't sound right .

It's better than licking the power cord...

Oh the lick method, I've tried that before. If I recall correctly, I could hear Purple Haze by Hendrix playing in my head.

ya i thought it was weird myself, i actually laughed at him...then i realized he was serious. He didnt really explain.

well guess what, it works now.

I decided to pop open my sub to see if anything obvious came loose. I noticed one of the speaker wires was not connected. I connected it and.... now it works. Must've came lose during shipping. So I called axiom and canceled the new sub shipment.

thanks for help.

jon

Glad to hear it was something simple. Enjoy!

>>well guess what, it works now.

Guess you weren't an idiot after all

Glad it's all working now. How does it sound ?

Funny how problems can sometimes be a very simple fix

Glad you got it going, hope you like your axioms once you get them all calibrated..

popped in a few dvds and sounds pretty good. now trying to decide on surroound speaker placement. I also need some stands for the fronts...anyone know where to find some nice cheap ones?

I have never dealt with this place but they are supposed to be pretty good :

http://www.racksandstands.com/

Depends on what you consider cheap. I like my Atlantis stands very much. Here's a link showing their product line. I'm sure if you Googled "Atlantis speaker stands" you could fine more than a few dealers. Perhaps start with Audio Advisor.

Jonn21,

Excellent detective work on your part finding the detached speaker lead. Sometimes the most obvious thing is the one easily overlooked (and I do this myself--sometimes choosing a complicated fix for something that's really simple). I'll add this to an article I'm writing on sleuthing out subwoofer problems.

I'm not sure which one of my colleagues suggested licking the RCA jack but I got a great laugh out of it. From a practical point of view, licking it might remove any oxidation or grease from an RCA plug if it was really old.

I'm glad you got your EP125 up and running.

Regards,

You might have to get a tetnis shot after licking off any corrosion

thanks ill check out the sites.

In reply to:

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I'm not sure which one of my colleagues suggested licking the RCA jack but I got a great laugh out of it.

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I dunno Alan, during my tenure as a human being I must admit that I have licked some things more questionable than an RCA jack...especially during my Army days, so maybe licking the RCA jack ain't so bad after all.

Yea go ahead and laugh...like some of you guys *never have*?

I don't know what you Army boys did but us Navy fellows were always on the best of behavor

Oh yea, I remember seeing you Navy dudes in Athens after parking your ships in Peiræus for a short stay...what a hoot!

It wasn't me, I was never in Athens .

RCA cables are one thing -- ewww. Now, licking the terminals of a new 9V battery, that's more like it.

that wasn't around 6/86 was it? if so......i wasn't there either.