Motorboating sound from amplifier (1 Viewer)

[Nathan Crowell]

I am getting a motorboating sound from my main speakers- ostensibly the source would be my Adcom GFA1A power amp. Other system components are an Adcom GFP1A preamp, Denon DCM370 CD player, and Audio Alchemy DDE 3.0 DAC. It will occur at random intervals, and occaisionally manifest itself as a burp or a long stream rapidly rising in pitch and speed.

This is very scary for me, because I have no idea what the problem is and if it could be potentially damaging to my main speakers or other system components. I would be grateful for any help. Thanks.

 

[Paul Clarke]

What else is connected on the line that feeds your system?

You need to isolate your system power feed with a dedicated circuit or UPS line conditioner or remove the offending appliance/device from the line.

 

[Michael Hurst]

I agree with Paul it sounds like an appliance is interfering with your power feed. The major culprits tend to be: refridgerator, air conditioners and halogen lamps. Next time you here the sound, start unpluging appliances until it stops. Once the culprit is found you can try a ferrite bead around it's power cord. Try some place like Diga-Key for beads, one of the better brands is Fer-Rite.

Nathan I used to live in Libertyville, IL. Saw the address and Lou Malnotti's Pizza came to mind. Are they still there? Best pizza I ever had

 

[Nathan Crowell]

Yeah, Lou Malnati's is still around.

I had all my equipment plugged into a Monster HTS3500, so supposedly all components are isolated from one another. I get the noise regardless of what the components are plugged into- the Monster or a $5 surge protector.

 

[Paul Clarke]

Which means the culprit is something else in your house that is plugged into the same line somewhere on that circuit, most likely upstream from your HT feed point. It doesn't have to be anything A/V.

Motorboating almost always involves a ground problem.