I have a K200B-1 that I recently purchased and want to use on a gig this weekend. The Bright channel adds considerable noise when the amp is idle.
In another post, someone came up with the idea of un-soldering the power to the PC board as a way of eliminating the noise. Is this valid?
From what I can see, the power is supplied by the red wire in this photo:
I plan on doing some repair work in the future to replace the resistors and caps if necessary but I want to get through this gig with diminished noise.
stevem Messages: 4743 Registered: June 2004 Location: NY
Senior Member
If I can add my 2 cents here I would unpower it by removing the red wire, as unhooking the blue would may invite noise pick up as you would have a open input and even though both preamp inputs to that transistor have 33k resistor they feed into you still can use the methode of shorting that unused blue wire to kill noise input.
So if I understand you correctly, if I was to unhook the blue lead to the poweramp, I ahould run it to ground to prevent noise entering from an open circuit.
stevem Messages: 4743 Registered: June 2004 Location: NY
Senior Member
On amps that are that dusty and with possible corrosion like yours I would slide the 4 slip on output transistor connectors up and down 3 to 4 times to clean off any possible garbage so they can pull the full current they need.
Already did. The pictures were taken immediately upon opening the amp the first time. I got contact cleaner from Rickety Shack and sprayed the pots and connectors.