Nashville 400 Amp Hum

Paul King · Post by **Paul King** » 12 Mar 2004 10:52 am

I have developed a hum in my Nashville 400 amp. I have bypassed everything and even tried different volume pedals. I am looking for some pointers from anyone who might have had a hum problem with their Nashville 400 and what the problem was and what an estimate was to repair it.

Erv Niehaus · Post by **Erv Niehaus** » 12 Mar 2004 11:00 am

Have you tried turning it on with nothing plugged into it? I had a hum one time and, lo and behold, I discovered a jack that wasn't plugged in all the way.
Erv

C Dixon · Post by **C Dixon** » 12 Mar 2004 11:17 am

Before taking it to a repair shop, simply reach under the amp and wiggle the molex plug coming from the reverb pan.

You just may save yourself a trip and some hard earned money. IF the hum goes away, turn the amp off; remove and reinsert the plug several times. This will tend to "clean" the pins. (NOTE: it is often very tight.)

For a longer lasting repair, procure some "contact cleaner" from Radio Shack and spray not only the plug's contacts, but the jack contacts on the amp as well.

This molex connector has caused a myriad of different symptoms; with hum being one of them.

CAUTION: If you have not turned your mid and shift controls in a while, do NOT adjust them with your amp on. Lest you hear an ear bursting pop that will make you think someone has shot you. Seriously I am dead serious about it. If you have not had this horrid experience, it is really a tremendously loud pop, if either of these controls is dirty and you go to adjust them.

Simply excercising both controls from one end to the other with the amp off will avoid this malady.

carl

Ray Minich · Post by **Ray Minich** » 12 Mar 2004 12:25 pm

Make sure none of them wall mount transformers or power strips are near the base of the amp. My hum was caused by the power pac/xfmr of the Peavey DeltaFex being right next to the base of the amp near the reverb tank. Just a thought.

Don Discher · Post by **Don Discher** » 12 Mar 2004 7:01 pm

Mine developed a hum and loss of power and it turned out to be the molex reverb plug,cleaned and re-set,no problem since.

Mike Brown · Post by **Mike Brown** » 16 Mar 2004 8:29 am

Contact me here at Peavey if I can be of assistance. Toll free in North America at 1-877-732-8391.

Mike Brown
Peavey Electronics Corporation

Paul King · Post by **Paul King** » 17 Mar 2004 5:35 am

Thanks guys for the advice. Also, Mike I appreciate your help from Peavey. That is one reason this forum is a great website. You can need help and people are willing to help out without even knowing me. I took the amp back to church and did not hear the hum until I really press the volume pedal down quiet a bit. I will have it looked at shortly.