Horrendous feedback type sound N112

LaVern Skarzenski · From: North East,Pennsylvania, USA

Hello All,
I have a Peavey Nashville 112 purchased new in 2003, label on front says Made in USA. It is setup in my music room and doesn't get moved or tore down anymore. I am having a problem that started about 6 months ago with a terribly loud, ear piercing feedback type noise when ever the Mids are turned on. As long as I turn them off (Counter clockwise) all the way it doesn't occur. It started out as only occasionally, but now it's to the point where I cannot have them on at all. I have tried various settings on every knob on the front panel and nothing changes. I have tried both the single cord volume and the double chord. I have tried guitar to volume pedal, pedal to amp. Everything I have read in the past about spraying the pots and cleaning the jacks with electronic cleaner. I have sprayed pot shafts from the outside with 'CRC QD Electronic Cleaner', rotating them, and did the same with the jacks by spraying and then inserting and removing a cable end but to no avail. Perhaps this is not the correct way to do it, so can somebody tell me what else I may do to alleviate this problem, short of shipping it to a repair shop, or is that the only thing that will work? Perhaps there is a better way to clean them. Thanks.
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GFI S10, BSG S10, Nashville 112, Digitech 155, DOD DFX9 Digital Delay, Goodrich L 120.

Jim Palenscar · From: Oceanside, Calif, USA

Change the mid pot

LaVern Skarzenski · From: North East,Pennsylvania, USA

Thanks for the reply. Is that something that requires any high skill electronics? I take it one must pull the top end out and some soldering would be required? I've made several lap steels and did the soldering required for them.
LaVern
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GFI S10, BSG S10, Nashville 112, Digitech 155, DOD DFX9 Digital Delay, Goodrich L 120.

Gil James · From: Louisiana, USA

Pretty common occurrence on these amps. The first time it did it to me, I about had a heart attack! I think my left ear was permanently damaged! My solution was to turn the gain and master all the way down, then rotate the mid knobs ferociously, ending them up in the correct positions, then slowly increase the gain. After about 2 or 3 tries it stopped. Then I put a piece of tape over those knobs. Lol. All I ever use it for is on one steel, so I've never had to change em. And didn't want anybody else fooling with them. It's never done it again. If you use it for other instruments,I'd take Jim's advice.

LaVern Skarzenski · From: North East,Pennsylvania, USA

I just took a look at it and first off I cannot make out how to disconnect the reverb tank. The connections don't look like any of the "molex" connections I've seen online. I did see a video on cleaning the pots where he removed the "head" on a Bandit 112, and it looks like the pot removal and replacement might be out of my league. I have a 112 Bandit and that doesn't sound too bad, perhaps that will be my amp for a while. Would like to find a Peavey dealer nearby that's certified for repairs. Thanks for the replies.
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GFI S10, BSG S10, Nashville 112, Digitech 155, DOD DFX9 Digital Delay, Goodrich L 120.

Stephen Cowell · From: Round Rock, Texas, USA

You can change the Mid pot (it's a specific dual pot) or you can yank the Mid chip to stop the squeal. Same thing happened to my N1000.
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Too much junk to list... always getting more.

Ken Fox · From: Nashville GA USA

Unless you have very good skills with desoldering you may easily destroy the traces on the board. There are 7 connections to be desoldered. 4 are the mounting bracket and 3 easy to burn up electrical connections for the pot itself
I would send it to Peavey or a local electronics repair shop

LaVern Skarzenski · From: North East,Pennsylvania, USA

Lee Baucum · From: McAllen, Texas (Extreme South) The Final Frontier

I just had a flashback to many, many years ago when some of us had our ears blasted by our Nashville 400 amps.

I believe it was the Mid-Shift pot. One little turn and it sounded like a bomb going off.

Shocked

I wonder how many of those tanks are still in operation out there. Practically indestructible.

~Lee

Richard Sinkler · From: aka: Rusty Strings -- Missoula, Montana

Dennis Saydak · From: Manitoba, Canada

What a coincidence to come across this thread just when I'm dealing with a really bad mid pot issue. I'm actually amazed to have this problem as I'm a “set it and leave it” kind of guy. My amp has only been moved once since I bought it new back in 2007; that was to install the chip mod package that I got from Mr. Fox. That was a relatively easy task as the parts were easy to access. However, that is not the case with pot replacement. Given how common this problem seems to be, I have to wonder exactly is causing this problem.

To gain access to the underside of the circuit board, there are 8 pots and 6 jacks that require removing the knobs and retaining nuts. That's means a lot of careful work to not break a knob or bend a shaft. My midi pot knob doesn't want to come off easily, so it looks like I'll have to carefully pry it and the others off after I make a notched tool for that task.

Anyway, here's a picture of the “innards” for someone thinking about doing this repair themselves. BTW, I do have the necessary experience with soldering to tackle the job myself. I just need to scrounge up a replacement part and that won't be easy since I don't have a local repair depot handy.
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Dennis
Just when you think you're getting ahead in the rat race, the rats get faster.

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