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Hissing amp

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(@artlutherie)
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Joined: 20 years ago
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Okay, so I've acquired a Peavey BackStage Plus circa Eighties from someone who owed me some cash. It was pretty filthy but all the knobs worked, so I took it home cleaned it up ( Armor All for the cabinet and a wet toothbrush for the cloth grill). It looks great now, but it's got a hissing going on when I'm not touching the strings or bridge on my guitar. Upon further inspection I noticed the plug is missing a ground someone just removed it. Could this be fixed by replacing the plug? Or is it a problem with my guitar? Or should I open the amp and hit it with electronics cleaner? Any ideas greatly appreciated.

Chuck Norris invented Kentucky Fried Chicken's famous secret recipe, with eleven herbs and spices. But nobody ever mentions the twelfth ingredient: Fear!
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(@forrok_star)
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Joined: 21 years ago
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Sounds like that missing ground may by the problem. Yes I would change the chord. Is there a polarity switch on it. Don't it will work right without the ground. I've been zapped more time than I count. That time playing at NAU when the melting snow came in under the wall and onto the stage. For about a week after that I only had to put the pluggin in my pocket for my amp to work...LOL

Joe


   
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(@artlutherie)
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Joined: 20 years ago
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Well, I replaced the plug, made sure the outlet was grounded, and hit the pots on the amp with electrical cleaner. There's still a buzz at mid volumes when I'm not touching the metal parts on mt Strat clone. Guess I'm doing a ruff and ready shield job tonight. :x

Chuck Norris invented Kentucky Fried Chicken's famous secret recipe, with eleven herbs and spices. But nobody ever mentions the twelfth ingredient: Fear!
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(@ricochet)
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Joined: 21 years ago
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I've got a really nasty looking old Backstage Plus that my mother got from somebody who owed her money. It's not half bad sounding!

"A cheerful heart is good medicine."


   
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(@artlutherie)
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Topic starter  

I've got a really nasty looking old Backstage Plus that my mother got from somebody who owed her money. It's not half bad sounding!

Yeah at low volumes it's great. I can't wait to hear it like it's supposed to sound.!!!

Chuck Norris invented Kentucky Fried Chicken's famous secret recipe, with eleven herbs and spices. But nobody ever mentions the twelfth ingredient: Fear!
ChuckNorrisFactsdotCom


   
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(@hueseph)
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Joined: 21 years ago
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Sounds like you're dealing with standard issue single coil hum. Nothing you can do for it short of sheilding or installing stacked humbuckers.

Here's a diagram and explaination of how to sheild your guitar:

http://www.guitarnuts.com/wiring/shielding/innards.php

Sheilding does wonders but it doesn't eliminate hum entirely. You have to be pretty meticulous with covering the entire inside of the body cavity including the space where your jack is with conductive paint or foil. If the circuit isn't complete, it won't work.

https://soundcloud.com/hue-nery/hue-audio-sampler


   
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(@hueseph)
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(@artlutherie)
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Wasn't aware you had to do the jack hole :oops: that's going to be hard to do and complete the circuit.

Chuck Norris invented Kentucky Fried Chicken's famous secret recipe, with eleven herbs and spices. But nobody ever mentions the twelfth ingredient: Fear!
ChuckNorrisFactsdotCom


   
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(@artguitarhendsbee)
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Joined: 18 years ago
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I've got a really nasty looking old Backstage Plus that my mother got from somebody who owed her money. It's not half bad sounding!
've acquired a Peavey BackStage Plus circa Eighties from someone who owed me some cash.

do many other people get backstage plus' from people who owe them money, how much money we talking about here?


   
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(@artlutherie)
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Well I got 'er done (sheilding) and I've definately Qiueted her down quite a bit now it looks like I'm going to have to replace a flakey 5 way switch. :x By the way anybody notice a difference in output with longer cables? I've got a 5ft and an 18ft and it seems I lose a loy of volume when using the 18 footer. Luckily I've got 35 watts to play with.

Chuck Norris invented Kentucky Fried Chicken's famous secret recipe, with eleven herbs and spices. But nobody ever mentions the twelfth ingredient: Fear!
ChuckNorrisFactsdotCom


   
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(@ricochet)
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Joined: 21 years ago
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You'll lose a little bit of volume with long cables, but you'll especially lose treble frequencies. There's a lot of capacitance in there.

"A cheerful heart is good medicine."


   
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(@xkmangwingx)
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Joined: 18 years ago
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you also loose some tone with really long cables due to impedance


   
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(@ricochet)
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It's the resistance-capacitance combination. Acts as a low pass filter.

"A cheerful heart is good medicine."


   
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