Mysterious power-amp hum with solid-state guitar amp

[HarpCat]

Hi,

I got a Behringer GMX 212 guitar amp in need of a repair and need some help.
There is a low-level 50Hz Buzz on the right speaker...

[showlyshah]

Hello all, i am new to this forum.

I am basically an electronics enthusiast. and recently my friend bring me some dynacords.
1. dynacord...

[NO-ALI]

hi everyone , its my first thread on this website , i just bought 2 rcf hps 1500 power amps , they are both faulty , i started working on them but i really...

[Petr]

Hi there,
Few days ago a friend of mine brought me his Laney DB300C bass combo for repair. Blown power amp. I have read this thread on this forum carefully...

[parentheticalfact]

Anyone have a recommended silicon replacement output transistor for the rhodes 80w peterson amp? Perhaps even some recommended replacement resistor values...

[cablercdd1]

I have a Ramsa WP-9110 power amp that we're looking to donate to a school. I replaced a driver transistor a couple of years ago and noticed it runs warm just...

[Mr.Lawnmowerman]

Hey guys, I have an EV SB120a I got for 20 bucks that has no output. It's a 400 watt class D powered 12 inch sub. On the power amp board an IR2110 went up...

[trojax]

Hi, I was recently working on finding a way to get my Bugera V22 amp signal to a direct box To do this I was running from my effects loop straight to the...

[Klaatuboradanikto]

Gentlemen, I'm new to building and am looking to make a low watt amp. I'm planning on using some early Fender pre-amp design. What I'm wanting for the power...

[Stoffie1974]

Hello,
I'd like to share this simple schematic of a very good clipping indicator. Most indicators measure the non amplified signal and take no account...

[Sloan]

I'm working on a Yamaha P4500 power amp here with distortion on 'Channel B' and I'm trying to track down the source. There is no DC on the speaker outs....

[docSanchez]

Hello everyone

I have an Alesis RA-150 that has been getting cranky over the last couple of months. At first the signal would just drop out...

[StratBastard]

Hi, I just picked up a really clean Audio Centron RMA-1600 power amp. It immediately blows the fuse as soon as the switch is flipped on. I opened it up and...

[snowballfight]

Hi

I have Merlin's book which is a great aid for desgining all the preamp and generally an introduction to tube amps. I'm wondering what is the...

[mattygeetarross]

Hi guys,
I have a CS800, s/n00-05985512, it's the "wind-tunnel" with the layout on the top cover, and plastic front cover.
It worked...

[magnus0]

I'm building a small amp with KA2206. Basically it works, but it's too quiet. How can I increase the gain on it. I know there are gain pins on other amps...

[magnus0]

TDA7052 power amp is not available here. What can I replace it with?

[BritishSteel]

Hi all, New guy here. I have a tech question for the repair guru's.
I have a Peavey 60/60 Pwr Amp works perfect, but, I would like to improve on what...