110RD-50 quit after an hour
jazzyybass
Hello
After about 1 hour my 110RD-50 quits. Completely silent.
When turning the amplifier off and on the amp works for about another hour.
Sometimes if I turned the volume knob the amp will work after a hard sound.
I put the original tubes back in, but the problem remains the same.
Replaced the TL072CP's, however this does not help.
Does anyone know what the problem may be?
Faulty pot or capacitors?
Thank you.
Full Name
Steve Kennedy
Music Man Equipment
Music Man 410-65 (1974)
Music Man 410-65 (1979)
Music Man 112RD-100 (1980)
Music Man 210RD-100-EVM (1982)
Music Man HD-130 Head (1975)
Music Man RD-50 Head (1982)
Music Man 112RD-50 (1982)
Music Man 410-65 (1979)
Music Man 112RD-100 (1980)
Music Man 210RD-100-EVM (1982)
Music Man HD-130 Head (1975)
Music Man RD-50 Head (1982)
Music Man 112RD-50 (1982)
Member for
11 years 1 month
Full Name
Rob Hazelaar
Music Man Equipment
112RD-65 (1978-1979)
110RD-50
110RD-50
Member for
10 years 6 monthsFull Name
Rob Hazelaar
Music Man Equipment
112RD-65 (1978-1979)
110RD-50
110RD-50
Maybe a Bad Solder Joint or Cracked Resistor!
Something sounds like it is opening or shorting a connection when the amp gets warm. The areas of failure that are the most notorious for this sort of behavior are resistors, semiconductors, output tubes and solder joint connections. Other things can also be responsible but if a problem is not obvious, take it to a good tech for classic troubleshooting to find the issue.
Most tube amps are NOT completely silent if you have a bad pot (even when it is shorted to ground). Standby mode (no DC voltage on the plate of the output tubes) also results in an absolutely silent amplifier (an intermittent B+ connection will also cause this symptom). Your amp doesn't have a standby switch so an intermittent connection could be involved. Also, a shorted D9 Zener or loss of 30Vdc on pin 5 of the output tubes can also cause significant silence.