Nashville 400 Humming Sound

Fred Nelson · Post by **Fred Nelson** » 31 Dec 2000 3:36 pm

Been useing this amp for several years no problems, all of a sudden the sound just goes away then it will come back. I can touch any metal part on the amp and it starts to buzz, plug in the guitar it buzz's, throw the ground switch it makes no difference. Please can anyone tell what may be the problem.
Thanks a lot

------------------

Gene Jones · Post by **Gene Jones** » 1 Jan 2001 12:07 pm

Are you sure someone didn't spill a glass or beer or coke on it when your back was turned and didn't tell you about it? That's what happened to one of my tube amps one time and it had the same symptoms...finally had to replace it.

Bob Metzger · Post by **Bob Metzger** » 2 Jan 2001 1:27 pm

If you're technically inclined, disassemble the amp and check all grounds, especially the AC power cord and the input jacks (and the 'patch in/out' jacks). Check that everything is tight and things haven't loosened up at all. The Pre-out and Power amp in jacks on the back panel have little switches internal to them that 'normal' the connection (like a patch bay) and these like to break sometimes. They're hard to fix and usually better replaced. Use some tech spray while putting a plug in and out of these. Look for broken wires (or nearly broken wires) going to the circuit board, especially ground wires (or shielded wires). I would unplug the molex connectors, making sure you make note which way they go back together and retension the female sleeves, using a good tech cleaner spray at that time. Be certain that the molex connectors are making a good connection after reassembly. Sometimes reseating the ICs in their sockets is a good idea. Gently push down on them to make sure they are making proper contact with their socket connection (gently, please). Also, be careful of static electricity when touching ICs; they hate it. Look for burnt resistors on the circuit board or discoloration on the board cause by excessive heat. A part nearby could be getting ready to join the big parts bin in the sky. When solid state amps break, about 90% of the time (or more), the problem lies in the power supply, as that is where all the heavy lifting occurs. Anything more than this visual once-over will call for test equipment and some electronics knowledge. On the other hand, Peavey does a good job of repairing their amps and they have generally excellent support for people who buy their products. Or look for a local tech who has had experience with the NV 400 or other Peavey amps (or other solid state amps).

If you look 'inside' yourself, make sure the amp is unplugged from the wall AC first and then, please discharge the filter caps before doing any poking and prodding around. If you need info on cap discharge, email me.

Bob

Skip T · Post by **Skip T** » 5 Jan 2001 11:00 am

Fred ,
Had the same problem and believe it or not - - it was my "volume pedal" causing the problem. Have you bypassed your pedal to see if it is the amp for sure ?
Skip T

Fred Nelson · Post by **Fred Nelson** » 7 Jan 2001 5:14 am

Thanks guy's for all your suggestions I tried them all plus about everything in the book, so I sent it back to Peavey for repair.
This forum has got to be the best site on the web.

Thanks a lot
Fred

------------------

Vernon Hester · Post by **Vernon Hester** » 7 Jan 2001 1:28 pm

Repaired a Vegas 400 yesterday,Bad ground on the reverb return.
Vern