Plz help, my Pc12-Ultra started buzzing

[spidey.joe80]

Hello there all.
I bought this sub used about 6 months ago and its been working great until yesterday. I had been tweaking crossover settings on my Yamaha amp and noticed a few crunchy popping noises during playback, then all of a sudden it started humming/buzzing fairly loudly. It only hums when plugged into RCA. Im really hoping my av reciever is dead and not my sub amp. Before this problem, if I turned the sub on before the reciever it would hum, but as soon as i turned on the reciever it would be reduced greatly: inaudible during playback. Now the humming gets louder when i turn on the amp(reciever). Also when I switch the crossover on sub to Disabled the hum changes to higher frequency. Pease help

 

[Bizarro_Stormy]

Have you checked the sub's port for a beehive...?

I hate bees...






especially the speeling kind...


er... spelling kind...




Sounds like a Sub amp problem... or a grounding issue...?

 

[Adam]

Welcome to the forum!

This might be a ground loop. Are the sub and receiver plugged into the same outlet or power strip/conditioner?

Also, it might be the RCA cable. Sometimes the connections between the cable and connectors get loose. You could try a different one to see if it makes a difference.

 

[spidey.joe80]

Ok, What a crazy day, after some troubleshooting the problem seems to have resolved itself... here's the story.
I talked to a svs tech and we seemed to have eliminated everything but the sub cable. So I exchanged with a shorter rca cable (2 feet) I noticed no buzzing and told the tech thanks then after i hung up i noticed the power on my sub was off...(had turned it off to exchange rca cables) i prayed then turned it on. No more buzz yay.
But now im using the longer cable and its still not buzzing. So maybe something in the cable was loose.

Also I almost destroyed my sub in the troubleshooting process by running the sub from a random rca out on amp. The gain was halfway up on sub holy crap it was loud! I bottomed it out hard, was so scary. Also after lowering the volume i could hear frequencies from the hundreds to i think 1khz!!(crossover on sub was disabled) So during the bottom out it got unfiltered full range signal jeez. anyone know if these old bash amps have limiter protection?
Sounds good now though. I think I dodged a bullet today. But somewhere in my mind I know I should start saving for the pc-13 ultra.

Thanks all

 

[FirstReflection]

The old BASH amps don't have a limiter or compressor, but they do have "soft clipping", so at least the very worst sort of potentially damaging signal is protected against

The Ultra drivers are extremely robust. Obviously, you don't want to be bottoming it out regularly. But a lone incident isn't likely to cause damage.

Glad to hear you fixed the problem! Probably just had a loose connection within the wire itself. With RCA cables, either the pin or shield lead can sometimes disconnect inside the RCA plug, and that would have caused your humming problem.

Easy fix, which is always nice

 

[Bizarro_Stormy]

So...

No bees...?