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Hoffman Amps Forum image Author Topic: Reverb Circuit Recommendations  (Read 1633 times)

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Offline Thisismyname

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Reverb Circuit Recommendations
« on: February 21, 2025, 01:48:51 pm »
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?

Offline SEL49

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Re: Reverb Circuit Recommendations
« Reply #1 on: February 21, 2025, 01:52:27 pm »
Show us a schematic of your amp as it is now, and you'll get some specific suggestions.

Offline Thisismyname

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Re: Reverb Circuit Recommendations
« Reply #2 on: February 21, 2025, 02:15:23 pm »
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+

Offline Jonas

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Re: Reverb Circuit Recommendations
« Reply #3 on: February 21, 2025, 02:17:30 pm »
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......
« Last Edit: February 21, 2025, 02:22:01 pm by Jonas »

Offline Thisismyname

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Re: Reverb Circuit Recommendations
« Reply #4 on: February 21, 2025, 02:58:59 pm »
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!

Offline Willabe

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Re: Reverb Circuit Recommendations
« Reply #5 on: February 21, 2025, 06:15:53 pm »
.... 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?

Offline Thisismyname

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Re: Reverb Circuit Recommendations
« Reply #6 on: February 21, 2025, 06:27:05 pm »
.... 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.

Offline Willabe

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Re: Reverb Circuit Recommendations
« Reply #7 on: February 21, 2025, 06:28:33 pm »
.... 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.

Offline Willabe

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Re: Reverb Circuit Recommendations
« Reply #8 on: February 21, 2025, 06:33:11 pm »
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? 
« Last Edit: February 21, 2025, 06:52:00 pm by Willabe »

Offline tubeswell

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Re: Reverb Circuit Recommendations
« Reply #9 on: February 22, 2025, 12:25:30 am »
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.
« Last Edit: February 22, 2025, 04:14:52 am by tubeswell »
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Offline Thisismyname

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Re: Reverb Circuit Recommendations
« Reply #10 on: February 22, 2025, 06:23:50 am »
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.

Offline Willabe

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Re: Reverb Circuit Recommendations
« Reply #11 on: February 22, 2025, 09:09:18 am »
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? 


Offline Thisismyname

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Re: Reverb Circuit Recommendations
« Reply #12 on: February 22, 2025, 10:06:18 am »
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.

 


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