Troubleshooting a non-functioning sub (or bass response)

[bradsmith]

Hey guys,

I've been having a bit of an issue with the bass response in my home theatre system. I wanted to check in for troubleshooting ideas before I tore everything apart. Here's what's going on:

Over the last few months I've noticed that occasionally I stop getting LFE response from my system when watching or listening to any source. I'm not entirely certain how long it stays that way (depends on how familiar I am with the source material and how close I'm paying attention).

Lately it's been happening more and more. I can get it to come back, often by unplugging the sub, powering down the towers and the receiver, then powering them back on. It would usually be fixed for a few days. Then last week, just a handful of minutes. Now I can't seem to reliably bring it back.

I've checked the connections and everything seems to be good. Test tones aren't coming out of the sub. It doesn't appear to be getting warm on the grill on the back.

Any ideas?

 

[j_garcia]

Sounds like the sub could be dying. Does it have an "auto-on" and an "always on" setting? Try setting it to always on to see if it is related to that. If that works, try upping the output level a few dB in the receiver and lowering it correspondingly on the sub's level.

 

[ImcLoud]

I had a sub problem and wanted to see if it was the signal or the sub, so when it went out, I plugged my ipod into the subs input with an 3.5mm x rca cable and the sub worked fine, come to find out it was in the avr programming, it would switch to direct when it played certain channels.... I fixed it with a new HDMI cable after talking to tech support...


First make sure you are getting lfe signal to the sub... and the sub has power...

if you are getting signal and the sub has power than it is the subs int. amp that has the problem...

If you dont have signal than it can be you sub connect cable, programming, source cables, ect....

 

[ImcLoud]

Also, what do you have for gear, sub ? Avr?

 

[j_garcia]

If your receiver has main preamp outs also, you can test using the main L&R to the sub and setting the mains to Large.

 

[bradsmith]

Hey guys. Thanks for the replies. I worked through all of your suggestions. No luck with anything, until I did some more wiggling with the cables. I have an RCA Y plug (I have no idea why) splitting the subwoofer cable to the L & R inputs on the sub. I removed it. It's working again. I feel so stupid right now. Why didn't I try that? I'm crossing my fingers that it wasn't just a coincidence, but it's been running good for a few hours now.

BTW, my system is a Denon AVR 1905 (I think that's the right number) and I have an AV123 (yeah, I know!) ELT 5.1 system.