Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Thisismyname on February 21, 2025, 01:48:51 pm
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I tried building a TW Express in a Deluxe Reverb chassis, but gave up trying to cure the gremlins. So I decided to bypass the cold clipper 3rd stage and use it as a clean amp. I'd like it to have reverb.
I know the AB763 reverb is great, but I have 4 triodes and many eyelets available, so I'd like to go as far as possible with this.
What are some exceptional reverb circuits I could put in this amp?
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Show us a schematic of your amp as it is now, and you'll get some specific suggestions.
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Here's what I used. How I bypassed the 3rd stage is by coming off the 2nd stage plate and going into a .0022uf cap as the PI input cap.
GZ34 rectifier. 480v unloaded B+, 380 loaded B+
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I am getting close to starting a capacitor driven reverb project based on the AMPEG Gemini II
uses 3 triodes, so you could re-visit the cold clipper triode later on......
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I am getting close to starting a capacitor driven reverb project based on the AMPEG Gemini II
uses 3 triodes, so you could re-visit the cold clipper triode later on......
Thanks!
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.... but I have 4 triodes and many eyelets available, so I'd like to go as far as possible with this.
What do you mean?
The TW Express uses 3 triodes, and are you saying you could add 4 more triodes/2 tubes to the chassis if needed?
If so will your PT be able to power the heaters, 2 x 300mA = 600mA?
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.... but I have 4 triodes and many eyelets available, so I'd like to go as far as possible with this.
What do you mean?
The TW Express uses 3 triodes, and are you saying you could add 4 more triodes/2 tubes to the chassis if needed?
If so will your PT be able to power the heaters, 2 x 300mA = 600mA?
It's the standard Deluxe Reverb PT, should it should.
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.... but I have 4 triodes and many eyelets available, so I'd like to go as far as possible with this.
What do you mean?
The TW Express uses 3 triodes, and are you saying you could add 4 more triodes/2 tubes to the chassis if needed?
If so will your PT be able to power the heaters, 2 x 300mA = 600mA?
It's the standard Deluxe Reverb PT, should it should.
I still have no idea what your saying.
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I know the AB763 reverb is great, but I have 4 triodes and many eyelets available, so I'd like to go as far as possible with this.
What does this mean?
That you only have 2 preamp tubes/4 triodes total for the preamp, PI and tube reverb?
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I was so impressed with the reverb from a M*****n SW22R that I serviced a few years back that I re-engineered my version of a schematic It's got loads of reverb for a 1-tube reverb, and although it only uses 3 x 12AX7s, it might work with the preamp in your concept.
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I know the AB763 reverb is great, but I have 4 triodes and many eyelets available, so I'd like to go as far as possible with this.
What does this mean?
That you only have 2 preamp tubes/4 triodes total for the preamp, PI and tube reverb?
DRRI chassis and iron. No 2nd channel, trem, reverb. 2 preamp tube sockets were removed years ago for a different project. So using this TW Express circuit, after the 2-stage preamp and PI tube, and after I remove the 3rd stage cold clipper I'm not using anymore, I have 2 tubes/4 stages free for whatever.
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DRRI chassis and iron. No 2nd channel, trem, reverb. 2 preamp tube sockets were removed years ago for a different project. So using this TW Express circuit, after the 2-stage preamp and PI tube, and after I remove the 3rd stage cold clipper I'm not using anymore, I have 2 tubes/4 stages free for whatever.
That's better but you still found a way to muck it up.
This part is still confusing;
So using this TW Express circuit, after the 2-stage preamp and PI tube, and after I remove the 3rd stage cold clipper I'm not using anymore, I have 2 tubes/4 stages free for whatever.
Basically what you have is a DRRI chassis and iron with a TW Express 2 stage preamp, a PI, 2 x 6V6 and you still have 2 tubes left that you could use for reverb?
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DRRI chassis and iron. No 2nd channel, trem, reverb. 2 preamp tube sockets were removed years ago for a different project. So using this TW Express circuit, after the 2-stage preamp and PI tube, and after I remove the 3rd stage cold clipper I'm not using anymore, I have 2 tubes/4 stages free for whatever.
That's better but you still found a way to muck it up.
This part is still confusing;
So using this TW Express circuit, after the 2-stage preamp and PI tube, and after I remove the 3rd stage cold clipper I'm not using anymore, I have 2 tubes/4 stages free for whatever.
Basically what you have is a DRRI chassis and iron with a TW Express 2 stage preamp, a PI, 2 x 6V6 and you still have 2 tubes left that you could use for reverb?
Yes.