Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: bakerlite on July 14, 2012, 11:48:19 am

Title: any info on dougs single channel ab763 amp?
Post by: bakerlite on July 14, 2012, 11:48:19 am

This is an amp i'd love to build.
Are there any layouts/schems knocking around?
is it just simply his ab763 layout with the normal channell removed and a dwell added to the reverb?
sounds super in his clips!
(hope its cool to ask)
thanks

Title: Re: any info on dougs single channel ab763 amp?
Post by: sluckey on July 14, 2012, 08:09:15 pm

There's a layout somewhere on Doug's site, but I don't remember where. Here's his layout as well as a schematic...

http://home.comcast.net/~seluckey/amps/misc/Hoffman_single_channel_no_trem_AB763.pdf (http://home.comcast.net/~seluckey/amps/misc/Hoffman_single_channel_no_trem_AB763.pdf)

Title: Re: any info on dougs single channel ab763 amp?
Post by: bakerlite on July 15, 2012, 05:53:27 am

maybe i am refering to a different amp.
I was sure it has the trem and reverb
(http://www.el34world.com/Hoffman/images/homebrew5.jpg)

Title: Re: any info on dougs single channel ab763 amp?
Post by: sluckey on July 15, 2012, 08:52:24 am

I've never seen a layout or schematic for the amp in that pic. The fact that there is a dwell and mix control for the reverb suggests that the amp is not simply Doug's AB763 without the normal channel. Using Doug's description and photos from the page where that pic came from should get you very close without an actual layout. Some of his other projects such as "Stout reverb" or "adding reverb to a Western amp" will give clues to the actual reverb circuit. If you need more info you'll have to ask the man.

EDIT... Here's Dougs special reverb wedged into a Plexi amp. Probably exactly what he did on the AB763 in your pic...

Title: Re: any info on dougs single channel ab763 amp?
Post by: proaudioguy on July 19, 2012, 11:48:37 pm

What is dwell?