A friend has a '67 that he wants to mod. Basically using the channels 3 and 4 for more gain. I was thinking of just adding a 5000pF on the volume 3 pot and a split cathode arrangements.
Another option I'm considering is doing a cascaded gain stage (ala JCM800) and tweak the values to his liking. The only thing I'm not sure about is that on this type of circuit, the Master volume is linked to the treble pot.
We want to keep the first two channels original. Would it work if the Treble wiper was connected to both the master volume (for channel 3 and 4 now converted to Master Volume and Gain) AND the .022uF in the PI?
Super P.A. (8 inputs) mod
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Stevem
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Re: Super P.A. (8 inputs) mod
Can you post up a schematic ?
It's been 30 plus years since I worked on one of those and if memory serves me right I may not be the best tube layout to try for a added gain stage deal?
That being said, there is tons of chassis area there to punch some new holes and move things around.
It's been 30 plus years since I worked on one of those and if memory serves me right I may not be the best tube layout to try for a added gain stage deal?
That being said, there is tons of chassis area there to punch some new holes and move things around.
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!