Subwoofer Out Problem (1 Viewer)

[John_JLtZD]

Hello, hopefully someone has some insight into a problem I am having with my reciever's subwoofer out.

I've been slowly upgrading my system, Ascend in the front, HTD in the back, and a Tempest/PE 250 sub so far. I just completed the wiring and was able to move the subwoofer from right next to my tv (where it is very much in the way) to the back of the room (which is in a diamond shape).

The trouble is, the sub is no longer receving signal. First thing I did was test my cables by hooking them up to a small stereo's aux input and cranking the crossover on my receiver all the way up - worked no problem. I then plugged the sub back in and nothing. So I plug the small stereo back in and nothing.

I next plugged an old vcr into the source end of the cables in place of the receiver and hooked the subwoofer up. It was faint, but signal was getting through to the sub.

I was able to get the small stereo to work with my recevier's sub out one more time before I gave up but never a peep from the sub.

My current thought is that it may be some type of protection circuit in the receiver (a JVC RX-884v) being overloaded. The cable run is somewhere between 30-40 feet. The sub has always worked great when it was plugged in with a six foot cable, but unfortunately, it must move.

I am planning to replace the JVC with an Onkyo sr-601 but I don't intend to do it this month and I want to work out this problem first.

Any insight or test I should try would be appreciated. I've boosted the sub signal as much as possible on the amp and swapped every setting I could back and forth.

Thanks,

JL

 

[Johnny Ayala]

Are you still using the same kind of connection? IMO, you should still be getting a signal even though you now have a longer run. Have you tried it with a shorter cable like you had it before?

 

[John_JLtZD]

Yes, I'm still using the same type of cable (dif brand, but still a sub cable). With a short cable it works, with the long run it sent signal to the mini-stereo I used for testing but stopped sending signal when I hooked the sub back up with the same cable.

JL

 

[Aaron Gilbert]

John,

It sounds to me like you have a bad subwoofer cable. The fact that you only had a faint signal when using the VCR as a source indicates something is seriously wrong. The audio output of a VCR is at line level, not a preamp output level like your receiver's subwoofer output. As such, the output level from your VCR should be close to the maximum out of your receiver. The sub should have been blasting. The fact that it works fine with your receiver and a different cable would indicate that both the receiver and subwoofer are working properly. And, since it also sounds like your small stereo system and VCR are working on their own, that leaves the cable.

If everything works with a shorter cable, there's no reason it should cease working with a longer cable. Some amplifiers can have a problem with auto-turn on circuitry with very long cable runs, but given your VCR experiment, I don't think this is your problem (not even sure your subwoofer amp has an auto turn on circuit?).


Aaron Gilbert