[gsxrmike]

I have a Denon AVR 2809-CI that I'm using to control a 5.1 set of Mordaunt Short speakers. The SW I'm using is a MS909W. My sub currently isn't working, and I'm not sure if it's the SW itself or the AVR. I've set the volume knob on the back of the SW to 12 o'clock, tried various frequencies, swapped cables, and I'm still getting nothing. Did a microprocessor reset on the AVR and the sub wasn't detected during Audyssey setup. All speakers are set to small (even tried large), but no luck. Yes, I've checked and I'm 100% positive the cable is in the SW Pre-out and not the EXT In port. What other ways should I troubleshoot this to find out what the problem is?

Thanks!

 

[jdsmoothie]

Pull the cable from the sub pre-out on the AVR and rub your finger over it the tip with the sub powered on. Hear anything? If no, either sub or cable is bad. If yes, AVR is bad.

 

[gsxrmike]

Pull the cable from the sub pre-out on the AVR and rub your finger over it the tip with the sub powered on. Hear anything? If no, either sub or cable is bad. If yes, AVR is bad.

Thanks, I tried it and got nothing at the AVR. My connection from the AVR goes like this: 3ft SW cable to SW wall plate, SW wall plate to 100ft cable, 100ft SW cable to SW wall plate, SW wall plate to 3ft SW cable. I even tried pulling the 3ft cable on the SW end from the wall plate and touching it. Still nothing. So should I assume dead SW? How likely is it the SW port on the AVR would go bad?

 

[jdsmoothie]

Thanks, I tried it and got nothing at the AVR. My connection from the AVR goes like this: 3ft SW cable to SW wall plate, SW wall plate to 100ft cable, 100ft SW cable to SW wall plate, SW wall plate to 3ft SW cable. I even tried pulling the 3ft cable on the SW end from the wall plate and touching it. Still nothing. So should I assume dead SW? How likely is it the SW port on the AVR would go bad?

If you're sure it's powered on, then yes.

 

[gsxrmike]

Ok, so I just did some more troubleshooting and here's what I came up with:

1) Tried swapping power cable - no difference
2) Connected to High Level connection from FL speaker input. SW worked
3) Disconnected High Level connection, then connected Line Level connection and SW immediately made a pop and cut out.
4) Pulled power cable, turned volume down to 1/3, plugged power back in, tested SW by touching tip of cable, made noise. As soon as variable notch filter was turned on SW made pop and cut out.
5) Pulled power again, turned variable notch off, volume at 1/3. Applied power again, SW worked, when volume turned up pop and cut out again.

It's almost like something inside keeps cutting into the circuitry to stop the sub from working (acting like it's overheating). Thoughts on this?

 

[JHAz]

A broken amp is, ummm, a broken amp. No magic will make it unbroken, and nothing you change in front of the input to the sub will let you troubleshoot problems after the input. Sometimes life sucks.

 

[gsxrmike]

If you're sure it's powered on, then yes.

JD - Big thanks for your time on the phone today. Appreciate all your help and wealth of knowledge

A broken amp is, ummm, a broken amp. No magic will make it unbroken, and nothing you change in front of the input to the sub will let you troubleshoot problems after the input. Sometimes life sucks.

True, just wish the AMP's were available to replace.

I've determined for sure it's not the Receiver. I have a small Lepai Amp that I use in my garage for audio. Brought it in and plugged the SW cable from the AVR into the L input, ran two speaker wires from it to a bookshelf speaker I have, and voila, it worked. This narrows it down to the SW Amp, as the SW driver itself works. Too bad I can't find a replacement plate AMP!