Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Tone Junkie on May 11, 2020, 08:49:01 pm

Title: What do you like best normal channel or vibrato channel on ab763 curcuit
Post by: Tone Junkie on May 11, 2020, 08:49:01 pm

Was thinking of building another single channel fender style . Wanted to know if you guys were like most of my friends who use these amps for there pedal platform and like the vibrato channel over the normal channel.Thanks Bill

Title: Re: What do you like best normal channel or vibrato channel on ab763 curcuit
Post by: Willabe on May 11, 2020, 09:49:33 pm

I want the mid range control. And that's on the vibrato channel, if the amp has a mid control. 

Title: Re: What do you like best normal channel or vibrato channel on ab763 curcuit
Post by: glass54 on May 11, 2020, 10:49:20 pm

Hi Bill
I built the a Single Channel, with optional Mid Control and Rev/Vibrato.
My friends who own Deluxe Reverbs, don't use the "Normal" Channel and their preference is Input 2 Jack (lower sensitivity) for their Pedal Board. (Input 1 for straight guitar)
Great Amp for clean work and with the pedals if required and not too heavy for us guys well over 50!!  :icon_biggrin:
Kind regards
Mirek

Title: Re: What do you like best normal channel or vibrato channel on ab763 curcuit
Post by: Tone Junkie on May 11, 2020, 11:44:52 pm

Cool thank you. funny after posting i remembered this was talked about before here. and there was even a schematic put up for it.Bill

Title: Re: What do you like best normal channel or vibrato channel on ab763 curcuit
Post by: Dave on May 21, 2020, 05:10:12 pm

So, here is something that I have done to give a "best of both worlds" scenario. Build either channel (after all, there are the same thing anyway), take the out put of that channel to a switch (DPDT) that either runs to the reverb/tremolo effects or straight to the PI. The other side of the switch takes the output of the tremolo recovery tube and either switches it to the PI (Opposite from the other side) or straight to ground. Then you have an normal channel that at the throw of a switch becomes the effects channel.


Dave

Title: Re: What do you like best normal channel or vibrato channel on ab763 curcuit
Post by: labb on May 21, 2020, 07:44:03 pm

Anyone tried the AB763 Deluxe without trem and with the normal channel mods from over at the Robrobinette site? Jack the preamp plate voltage up from about 170 to 210, do a little voicing with about 3 component changes headed towards the Marshall plexi type and add a Vox type master volume controll. As for the mid range, replace the 6800 resistor with a 10k pot. Up the pre amp plate resistors from 100k to 200k, 

Title: Re: What do you like best normal channel or vibrato channel on ab763 curcuit
Post by: Dave on May 21, 2020, 08:00:37 pm

Yeah, I built an AB763 one time with the normal channel stock and the other channel a screaming high gain tyrannosaur with a couple of extra gain stages and a completely different circuit and then ran them both through reverb/tremolo. Pretty cool.