Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Rockranger on November 21, 2019, 06:06:01 pm

Title: Hoffman 6v6
Post by: Rockranger on November 21, 2019, 06:06:01 pm: Hey, I have built the Hoffman 6v6 a year ago and love the amp, a friend inquired about me building a higher wattage version of the same amp for him, but I have only built a couple of amps sticking closely to the schematics. Just wondering if perhaps a 6L6 version of this is possible, what I would have to change, and what transformers I would need if it is possible, any insight at all would be greatly appreciated.

Thanks
Title: Re: Hoffman 6v6
Post by: shooter on November 21, 2019, 06:14:42 pm: which 6V6 the 5f1, 5e3 champ? plexi?, :dontknow:
Title: Re: Hoffman 6v6
Post by: Rockranger on November 21, 2019, 06:41:43 pm: Sorry guys the plexi 6v6!
Title: Re: Hoffman 6v6
Post by: sluckey on November 21, 2019, 06:54:06 pm: Look at Hoffman's Plexi50.
Title: Re: Hoffman 6v6
Post by: Rockranger on November 21, 2019, 07:13:42 pm: Yeah I was thinking that may be the answer thanks, really liked the American style tubes (6V6) version, would it be possible to do 6L6’s in the plexi 50 or is it best to stick with the el34’s. Really love the clean sound of my plexi 6V6, was really hoping to achieve the same on the higher wattage version.
Title: Re: Hoffman 6v6
Post by: EL34 on November 22, 2019, 05:38:29 am: The only difference between a 6V6 amp and a 6L6 amp would be the transformers
Title: Re: Hoffman 6v6
Post by: shooter on November 22, 2019, 09:42:12 am: Quote
be possible to do 6L6’s
it is but there's things you have to hunt down;
filament draw between 34's vs 6L6
Ra-a from tube datasheets for fixed bias PP EDIT: at the aprox plate B+

those 2 things will determine how or if the iron needs to be different
Title: Re: Hoffman 6v6
Post by: DummyLoad on November 22, 2019, 02:43:14 pm: build hoffman 50W plexi - tweak bias power supply for 6L6.

you could also design bias variance range to accommodate either 6L6 or EL34. switchable would work best.

--pete
Title: Re: Hoffman 6v6
Post by: Rockranger on November 25, 2019, 07:58:32 am: Quote from: EL34 on November 22, 2019, 05:38:29 am
The only difference between a 6V6 amp and a 6L6 amp would be the transformers
.
Just wondering if you have transformers that would be appropriate for this build?
Title: Re: Hoffman 6v6
Post by: sluckey on November 25, 2019, 08:15:47 am: I think Doug is out of the transformer business. Just get a set of iron for any Fender 6L6 amp (Super Reverb, Bandmaster, etc.) or any Marshall 2xEL34 amp.
Title: Re: Hoffman 6v6
Post by: EL34 on November 25, 2019, 08:41:41 am: Quote from: Rockranger on November 25, 2019, 07:58:32 am
Quote from: EL34 on November 22, 2019, 05:38:29 am
The only difference between a 6V6 amp and a 6L6 amp would be the transformers
.
Just wondering if you have transformers that would be appropriate for this build?

I have links here for all the discontinued stuff
Look here for transformer links
https://el34world.com/Forum/index.php?topic=23827.0 (https://el34world.com/Forum/index.php?topic=23827.0)
Title: Re: Hoffman 6v6
Post by: Rockranger on November 25, 2019, 01:09:32 pm: Thanks guys, Living in Canada I have access to the Hammond super reverb style transformers, I am assuming I would use the large fender style choke instead of the small as well?