Vegas 400 reverb feedback

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Jim Hinton
Posts: 174
Joined: 26 Aug 2004 12:01 am
Location: Phoenix, Arizona, USA

Vegas 400 reverb feedback

Post by Jim Hinton »

I have a Vegas 400 that was build around 1982, and works pretty good. I just installed the tone enhancement kit (I am an engineering technician), and it works nicely.

I played a job last night, and the reverb wants to feedback at any setting above 4. I like the "wet sound" I get from using a fair amount of reverb, and hate it when I can't turn it up at least to 6.

Does anyone know how to "tame this beast"? I'm very technically capable, but really don't know much about audio (except what I've had to learn to keep my antique stuff working)

Thanks in advance for any advice or assistance.

Jim Hinton
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b0b
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Post by b0b »

Moved to the "Electronics" section of the Forum.
Bill Crook
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Post by Bill Crook »

Jim.......

Try to move the reverb pan more away from the amp chassis. Whats happening here is the output of the verb pan is getting back into the front of the amp.

The fix may be just as simple as physically turning the pan around 180 degrees and locking it back into place. DO NOT SWAP THE RCA CONNECTORS.
Mike Brown
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Joined: 4 Aug 1998 11:00 pm
Location: Meridian, Mississippi USA

Post by Mike Brown »

Jim, call me toll free if you cannot resolve the problem. I-877-732-8391 until the hurricane gets too close.
Jim Hinton
Posts: 174
Joined: 26 Aug 2004 12:01 am
Location: Phoenix, Arizona, USA

Post by Jim Hinton »

Hi Bill and Mike:

I have found the cause and fixed the problem. You are both correct in that the cause of the problem was the routing of the power wires.

Years ago, sometime in the 80's, a friend of mine installed a power outlet duplex box, so that I could plug "other gadgets" in when I needed to.

Since I have just installed the "tone enhancement kit" in my amp, one of two things has happened. I either re-routed the wires so that they were too close to the reverb unit, or the frequency response has been shifted by the tone kit, and is now more susceptable to 60 cycle hum.

Maybe both conditions contributed to the problem.

Anyway, I rewired the power input wires and duplex box, and moved it as far away from the reverb as I could.

I can't make the reverb feedback now ... at least in my house. I guess the acid test will be when I play at the saloon I was in, when the problem first occured, which will be this Sunday afternoon.

My sincere thanks for all the kind suggestions and emails how to rememdy this malady!!

You guys are great!

Jim

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