Nasville 400 Reverb hums

Ray Minich · Post by **Ray Minich** » 7 Nov 2003 6:34 pm

And it don't hum 'cause it dont know the words...

My NV400 is nice and quiet (as in hum free) until I turn up the reverb control whereupon said hum doth increase by a heckuva lot...

I already removed and replaced the reverb unit after reseating the audio connectors on both ends of the cables in the process, and it still hums...

Any suggestions, is there a capacitor that needs replacement?

Thanks in advance for any help.

Russ · Post by **Russ** » 7 Nov 2003 8:11 pm

Make sure there is no ac Adapter or Tranformers near the Amp. I had that trouble and it was an Ac Adapter setting to close to the Reverb unit. Just an Idea.

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Russ Kern

Brad Sarno · Post by **Brad Sarno** » 7 Nov 2003 8:39 pm

Those reverb tanks will hum in a noisy place. They act sort of like single coil pickups and I haven't found any way around it other than digital reverb units. Sometimes you can rotate the amp position to find a null or a quieter position.

Brad Sarno

D Schubert · Post by **D Schubert** » 7 Nov 2003 8:44 pm

I know it sounds dumb, but it worked for me. Try reversing the "input" and "output" wires to the reverb tank.

Harold Parris · Post by **Harold Parris** » 7 Nov 2003 8:46 pm

Make sure you don't have your reverb cables reversed. You can swap them around if you have any doubt that they are not right without causing any bad effect. I know if you get those leads crossed up a Peavey will hum in the reverb circuit although the reverb will still work. I assume most all amps will do the same.

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Sierra Session and MSA Classic Guitars, Nashville 400, Session 400, and Evans FET 500 HiVolt, and Gretsch Nashville Pro Steel Amps, Keith Hilton Digital Sustain pedal and Digital Sustain Box .
Harold Parris email hparris9@aol.com

Tom Ward · Post by **Tom Ward** » 8 Nov 2003 5:13 am

Ray, Try a jumper wire from the reverb tank to chassis of the NV 400 (Don't worry, you won't get shocked). If hum goes away you probably have a broken printed board connection or a bad solder connection to the reverb connector on the board. Let us know. Tom

Tony Prior · Post by **Tony Prior** » 8 Nov 2003 8:21 am

Also try cleaning all the connectors, all of them.

The goes'inta's and the goes'outta's.

These amps are very well known for dirty or weak connections causing mysterious things..like noise.

good luck

tp

Ray Minich · Post by **Ray Minich** » 8 Nov 2003 7:01 pm

Thanks everyone for the suggestions and recommendations. I'm gonna try them all in order to get rid of this annoyance.
BTW, the wall mount transformer for my DeltaFex was, in fact, plugged into an extension cord and was laying on the table snuggled up close to the NV400. I Moved it immediately. Some improvement noticed.

Today the manager at my local Peavey store said that "spring sag" in the reverb tank will make the reverb hum. He said a new reverb tank would cost about $75.00. Does anyone know if there is any reality to his statement or is he wanting to sell me a reverb tank I really don't need.

Again, I really appreciate everyone's help on this issue.... thanks a bunch.

David Doggett · Post by **David Doggett** » 8 Nov 2003 8:20 pm

Ray, it's almost always what Tony said, the molex connectors from the amp to the reverb and back. Clean those first and it'll probably sound fine again.