Help with sudden, strange noises

[macdaddyjakarta]

Hi out there,

Looking for some troubleshooting help.

I have a Yamaha Rx-1400, with my fronts pre-outed via a couple of monoblocks. Ihave a CD, DVD, sat receiver, and VCR all hooked up as well as a TV.

When I turn on the yammy, whether or not the monos are powered on, there is a fairly thoaty 'whomp' coming through the woofers of both left and right speakers. If I go from mute to -79 db, or back again, the same sounds happens, as when I power off. there is no other humming or hissing, just these whomps when powering on or off. Now if I switch to CD mode and play a CD, it sounds fine.

Any ideas? I've had the system since September with no problems.

Thanks for anyone's help,

chris

 

[Doug917]

Hello,

I used to have a similar problem with my old receiver when I would power on my amp for the subs. I ended up using a line conditioner Monster HTS-5000 and put the amp on a delayed circuit. Problem gone. I might be able to help more if I knew if the amps are plugged into the same outlet, do you plug anything (powerwise) into the receiver, etc. If you take the amps out of the circuit, does the problem still occur?

 

[zipper]

I also have a Yamaha receiver & am using an older B&K amp to drive my mains..........same problem, but only when I power the amp down. Have also noticed it when changing formats(like from stereo to DD)...........I was using some other amps for a while & I didn't have the problem with those, so I'm writing it off to the B&K, not as a problem, but just a characteristic of the amp.

I try to make sure I have the volume down when I change sources or formats or turn the amp off, but it doesn't seem to matter much. Still, it just seems like a good precaution.