Sub making randon boom

[DTRUTH]

I'm hoping someone has some ideas on this one as I'm out.

My brother has a Velodyne 1210 that he got back in 99, I believe. He has a Sony receiver from the same time period, but I don't know the model number. Everything appears to be set up correctly and the sub sounds fine when used for music or HT, but it randomly makes a loud boom.

Has anyone seen/heard anything similar to this or have any ideas on how to fix it.

Here are the settings that I can remember.
All speakers set to small.
On the sub:

Lowpass xover 80Hz
Highpass xover 100Hz (I believe)
xover OUT (I believe)

He's not using the line out, so the highpass should be irrelevant (I believe) and with the xover set to out,this should bypass the subs internal xover.

Thanks,
DTruth

 

[Sheep]

If anything, its the amp, or connection. My old sub cord (RCA type) didn't make a good connection, and when ever got bumped, it would let out a 60hz hum. It would even do it randomly. If not one of those, the reciever could be screwing up and sending a signal. Try hooking up another reciver and a new cord. If that doesn't fix it, then its something in the sub, which you should leave to velodyne to fix.

Hope that helps,
The Sheep

 

[tbewick]

It could be exciting a room node. Try moving the subwoofer aorund to see if that helps.

 

[patnshan]

I had an issue like this with my BIC sub. It would go on whenever it liked, and make a loud hum. It's funny, 60 Hz sounds about right, but I didn't meter it.

I called tech support and they recommended I plug it into the same outlet as the receiver. Since that, I have had no more problem. I think they mentioned it as a possible ground loop problem.

Good luck,

Pat

 

[DTRUTH]

If anything, its the amp, or connection. My old sub cord (RCA type) didn't make a good connection, and when ever got bumped, it would let out a 60hz hum. It would even do it randomly. If not one of those, the reciever could be screwing up and sending a signal. Try hooking up another reciver and a new cord. If that doesn't fix it, then its something in the sub, which you should leave to velodyne to fix.

Hope that helps,
The Sheep

He originally thought it might be the sub and sent it back to CC for repair, but they indicated there was nothing wrong with it. I'll try swapping the cable first and then the receiver to see if that changes anything.

It could be exciting a room node. Try moving the subwoofer aorund to see if that helps.

He has it inside of his entertainment center. That is, he cut the back out of the EC so he could hide it in the lower storage area behind the doors. The EC takes up the entire wall and his existing sub cable isn't long enough to allow for replacement.

I called tech support and they recommended I plug it into the same outlet as the receiver. Since that, I have had no more problem. I think they mentioned it as a possible ground loop problem.

Cool. I'll have him try that too.