Rev-A-Loop Revisited

[glasman]

Well after much troubleshooting of ground loops the beast is completed. Overall I am very pleased with the sound and depth of the reverb and loop operation. As soon as I finallize the schematic I will post it in the files section. I will also post some sound clips of the reverb tomorrow.

Original plan was to use a 12AT7 for the reverb driver and two sections of a 12AX7 for recovery. In practice it was found two recovery stages was too much reverb. A single stage is MORE than enough. I will probably end up paralleling the two 12AX7 sections for the recovery amp.

The basic circuit drives the reverb from the output of the Cathode follower in the D-loop using a 470pf cap. The reverb recovery is fed back into the grid of the D-Loop recovery amp via a 220K resistor. I also had to do a little shaping of the recovery amps low end response (Rk/Ck) to eliminate a low frequency (60hz) noise that was being picked up by the reverb tank.

Panel Controls,

Loop = Send Bright, Send Level, Return Level and Return Bright.
Reverb Section - Dwell, Level and Tone.

Here are a few pictures of the completed unit. If you have any questions, just ask... Still have a few things to clean up in the wiring.

Gary

[Bob-I]

Very cool unit Gary. I can't wait to see the finished schem and hear it.

[MarkB]

Gary

Nice build. What size unit is that?

[glasman]

Gary

Nice build. What size unit is that?

The unit was built in a 17x10x3 Hammond steel chassis I had sitting around the last couple of years. I had to remove the tank from it's housing to make it fit in the chassis. If I did another, I would remote the tank ala Fender Reverb unit. Would have been a LOT easier to make work correctly.

Gary

[PaisleyTube]

Hi Gary

Nice job!!!
Greetings from Chris-CMW

[glasman]

Hi Gary

Nice job!!!
Greetings from Chris-CMW

Hey Chris, how are thing in the Netherlands. I am flying to Eindhoven next weekend (Mar 17) and will be there for two weeks.

How is the weather, I have been hearing it has been COLD!!

Gary

[PaisleyTube]

Hi Gary

Slightly better than last weeks but kinda gry/rainy from time to time, I'm waiting for sunny spring/summertime...
Very busy with mods, pedals since some months and pre-work needed to put some amps on the market.

Let me know when you're in the neighbourhood. We can talk amps over here, have a few drinks and you're invited for dinner.

Later,

Chris (info AT cmwamps DOT com)
Vleuten, next to Utrecht

[glasman]

Hi Gary

Slightly better than last weeks but kinda gry/rainy from time to time, I'm waiting for sunny spring/summertime...
Very busy with mods, pedals since some months and pre-work needed to put some amps on the market.

Let me know when you're in the neighbourhood. We can talk amps over here, have a few drinks and you're invited for dinner.

Later,

Chris (info AT cmwamps DOT com)
Vleuten, next to Utrecht

Very cool Chris I will drop you a note when I hit Eindhoven and we can set somehting up. Driven through and around Utrecht many times over the past 22 years.

Gary