Losing highs and power mid rehearsal
- Thread starter emilio
- Start date
Gtrjunior
Well-known member
Losing highs and power mid rehearsal
I would suspect the power tubes first.
Many times caps will "swell" or look puffy when they need replacing. They are relatively cheap, I'd have my tech replace them if I were in your situation. Tubes too...probably cost about $150, maybe a little bit more. Assuming you have 4 power tubes.
I would suspect the power tubes first.
Many times caps will "swell" or look puffy when they need replacing. They are relatively cheap, I'd have my tech replace them if I were in your situation. Tubes too...probably cost about $150, maybe a little bit more. Assuming you have 4 power tubes.
Kamanda~SD
New member
Re: Losing highs and power mid rehearsal
Yeah I'd start with Tubes. How old are the one's in there?
Caps usually last a long time, but looks for what Gtrjunior said just incase.
Yeah I'd start with Tubes. How old are the one's in there?
Caps usually last a long time, but looks for what Gtrjunior said just incase.
Joey Voltage
New member
Re: Losing highs and power mid rehearsal
Most of the time the capacitors in question which use a wet electrolyte, will have a life that depends on the environment and the conditions in which they are used. The typical life estimate people usually throw around is 20-25 years under normal use, but there really isn't a hard set life. And newer variations especially ones designed for ballast applications, can have a life that far exceeds this. That said, they are usually not the first suspect when tracking down a problem like you describe, although the symptoms are similar. Always try the plug and play first before worrying it's something worse.
Most of the time the capacitors in question which use a wet electrolyte, will have a life that depends on the environment and the conditions in which they are used. The typical life estimate people usually throw around is 20-25 years under normal use, but there really isn't a hard set life. And newer variations especially ones designed for ballast applications, can have a life that far exceeds this. That said, they are usually not the first suspect when tracking down a problem like you describe, although the symptoms are similar. Always try the plug and play first before worrying it's something worse.
Gtrjunior
Well-known member
Re: Losing highs and power mid rehearsal
You would need the amp to be up at full operating temp to see any bulge in the caps.
You would need the amp to be up at full operating temp to see any bulge in the caps.
Joey Voltage
New member
Re: Losing highs and power mid rehearsal
If it's that old, it's probably time to have them replaced anyway.
If it's that old, it's probably time to have them replaced anyway.
GoldenVulture
Braindeadologist
Re: Losing highs and power mid rehearsal
Dying caps don't always show by bulging. That amp is thirty years old and if it's never had a cap job it probably needs one by now
Dying caps don't always show by bulging. That amp is thirty years old and if it's never had a cap job it probably needs one by now
Diego
New member
saxmo
New member
Re: Losing highs and power mid rehearsal
I believe that a passive treble(as well as Bass And Mids) often pass thru a pre-amp tube 12au or ax7 B4 the power tube stage or at least , they do on mine. If the pwr tube swap doesn't work, a pre-amp tube swap may. An intermittent, failing pre-amp tube once drove me nuts.
I believe that a passive treble(as well as Bass And Mids) often pass thru a pre-amp tube 12au or ax7 B4 the power tube stage or at least , they do on mine. If the pwr tube swap doesn't work, a pre-amp tube swap may. An intermittent, failing pre-amp tube once drove me nuts.
Similar threads
