Fender Quad Reverb (Power amp section dead)
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stratoflight
- Posts: 2
- Joined: Mon May 25, 2015 10:47 pm
- Location: Tacarigua, Venezuela
Fender Quad Reverb (Power amp section dead)
So i have this Fender Quad Reverb from 1971.. I Tested and no sound came out of it after putting new ruby 6L6's tubes. So i did a quick check into it. and the filter caps were bubled, this can be a cause to the power amp section to be dead? also the 470k resistor on one of the power tube socket was broken.
reverberizated
Re: Fender Quad Reverb (Power amp section dead)
Yes, your amp should not be powered on with the conditions you spotted.
I build and repair tube amps. http://amps.monkeymatic.com
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Stevem
- Posts: 4576
- Joined: Fri Jan 24, 2014 3:01 pm
- Location: 1/3rd the way out one of the arms of the Milkyway.
Re: Fender Quad Reverb (Power amp section dead)
The amp needs all new filters ( main power supply and bias power supply ) even the 25 uf ones on the preamp section black oil board.
Take a good look at all of those 470 ohm resistors and on the socket with the bad one the 1500 ohm resistor may be gone also!
When you done with the fix up, and before you put the output tubes back in confirm that you have at least a minus 48 volts on pin 5 of each output tube socket.
When you order up a new filter for the bias section get one with a 75 to 100 volt rating, I use 100 uf @ 100 volt filters for a more stable bias when the amp is cranked!
Take a good look at all of those 470 ohm resistors and on the socket with the bad one the 1500 ohm resistor may be gone also!
When you done with the fix up, and before you put the output tubes back in confirm that you have at least a minus 48 volts on pin 5 of each output tube socket.
When you order up a new filter for the bias section get one with a 75 to 100 volt rating, I use 100 uf @ 100 volt filters for a more stable bias when the amp is cranked!
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
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stratoflight
- Posts: 2
- Joined: Mon May 25, 2015 10:47 pm
- Location: Tacarigua, Venezuela
Re: Fender Quad Reverb (Power amp section dead)
Some pics... This chassis had seen better days... dont ya think?
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reverberizated
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Stevem
- Posts: 4576
- Joined: Fri Jan 24, 2014 3:01 pm
- Location: 1/3rd the way out one of the arms of the Milkyway.
Re: Fender Quad Reverb (Power amp section dead)
Nah, you should see a 65 a Bassman I have, it was left outside all last Summer, yes, just the chassis !
By some miracle all it needed was filters and the main reason it was toss, a PT!
By some miracle all it needed was filters and the main reason it was toss, a PT!
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!