Electrical incompatibility - Nashville 400

Tom Palmer · Post by **Tom Palmer** » 12 Apr 2003 8:57 pm

Has anyone experienced any electrical incompatibilty with a Nashville 400 in places that have extremely old electrical circits? I went to play at a jam last weekend, set up and waited my turn. When my turn came I turned on the amp and it just screamed with a sound like a high pitched feedback. I turned it off, checked all of my connections, turned it on again with the same result. Then I eliminated all my effects and went directly from the steel to the volume pedal to the amp with the same result. Then I unplugged everything from the amp and turned it on again with the same result. Then I changed the plug from the power strip to the wall with the same result. I unplugged, packed up, and went home scratching my head. The amp worked the night before and low and behold it worked fine when I got home. Any ideas?

Jim Bob Sedgwick · Post by **Jim Bob Sedgwick** » 12 Apr 2003 9:19 pm

Maybe it didn't like the place. (Sorry), I just couldn't resist. I wish I had an answer, but I don't. Maybe some of the real electronic geniuses can help.[This message was edited by Jim Bob Sedgwick on 12 April 2003 at 10:19 PM.]

Donny Hinson · Post by **Donny Hinson** » 13 Apr 2003 8:59 am

Were there any other amps there? Did they have a problem? If anyone else had an amp, and didn't have the same problem, it's probably safe to assume it was your amp causing the ruckus. I've never heard of squealing or feedback coming from a power source. "Hiss", "hum", "clicking", "popping", "buzz", yes. "Squealing", no.

Cause? Most likely a bad cap in the amp, or a problem with the connections to the reverb tank.

Paul Osbty · Post by **Paul Osbty** » 13 Apr 2003 11:35 am

It also sounds like there may have been a noise source that your amp was susceptible to. An air conditioner, neon sign, etc.? Funny that you didn't hear problems from any other equipment that night.

Next time, I would try going to the other side of the same room and using a different AC plug, hopefully on a different circuit breaker.

Tom Palmer · Post by **Tom Palmer** » 13 Apr 2003 11:56 am

There were other amps opperating there that day without a problem. However, a couple of people came up to me and said the place had a reputation for causing unusual electrical abnormailities in equipment that funtioned normally elsewhere.

I received the following reply from Larry Clark via e-mail which I believe hit the nail on the head.

"Hey Tom, sounds like you might be experiencing the Molex connector problem. If you trace the wiring from the reverb tank to the underside of the amp section of your Nash you will see a white plastic connector about an inch and a quarter long. With the amp unplugged, unplug the connector and spray it with some electronic contact cleaner(DeOxit D5 is about the best if you can find it). Spray both sides and plug and unplug the connector a few times to "clean " the contacts. That may well solve your problem. That Molex connector on the Nash has been "thorn in the ass" of an otherwise trouble free amp."

I thought I would post his reply for those who have not experienced the problem but will help them recognize it when and if it happens.
It certainly caught me off guard.

Thanks to all of you for your thoughts and ideas.[This message was edited by Tom Palmer on 13 April 2003 at 12:56 PM.][This message was edited by Tom Palmer on 13 April 2003 at 12:58 PM.]

Ole Dantoft · Post by **Ole Dantoft** » 13 Apr 2003 12:15 pm

Tom,
I have a Nashville 400 and yesterday evening I experienced exactly what you describe, only in my case it started with the reverb disappearing alltogether. I then reached for that molex-connector, and as soon as I touched it (with the amp still being "on") I got a horrible scream from the amp. I then turned it off, cleaned and re-seated the connector and everything has been A-OK since !

Ole
[This message was edited by Ole Dantoft on 13 April 2003 at 01:17 PM.]

C Dixon · Post by **C Dixon** » 13 Apr 2003 1:29 pm

Yes,

I must agree with the last two posts. I believe you may have been the victim of a coincidence.

That is, it would have happened anywhere IF that molex plug was in fact the problem. Which 99% of the time it is. It just decided to show up, IMO, in that place that night. Possibly having been jarred a bit in the ride to the place.

Try wiggling the molex plug coming from the reverb pan. You will probably be able to recreate the problem. If so, cleaning it is the answer. "Contact cleaner" from Radio Shack works fine.

While you are at it, cycle all the controls from one end to the other several times to remove bits of oxidation off the control's wipers. CAUTION: make SURE you have the amp OFF when you do this unless you want to go deaf.

IF there is oxidation and you clear it with the amp on, you will hear the loudest pop imaginable (almost).

carl

Mike Brown · Post by **Mike Brown** » 14 Apr 2003 11:05 am

Could be a number of things, ie; open input jack, reverb connections, bad ground in the wiring of the building. But, if I had to guess, I'd check the reverb circuit.

If you need further assistance, please don't hesitate to contact me here at Peavey. I can be reached toll free in the U.S. at 1-877-732-8391.

Thanks for using Peavey.

Mike Brown
Peavey Electronics Corporation

jim milewski · Post by **jim milewski** » 15 Apr 2003 11:28 am

did you try kicking the amp

Fred Shannon · Post by **Fred Shannon** » 15 Apr 2003 11:43 am

[This message was edited by Fred Shannon on 06 December 2004 at 02:23 AM.]

Mike Brown · Post by **Mike Brown** » 15 Apr 2003 11:58 am

Jim, let me know what you find out and I'll be glad to assist you from there.

Eddie Malray · Post by **Eddie Malray** » 25 Apr 2003 7:53 am

Tom: A friend of mine bought a used Session 400 Limited a few weeks ago. It worked great in the store. The First time out it had the same problem. The problem was a reverb tank connection. No more problems since the repair.----Eddie