Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: joesatch on March 07, 2022, 02:15:12 pm

Title: Preamp tube proximity. marshall mod
Post by: joesatch on March 07, 2022, 02:15:12 pm
Embarking on a #36 style mod to my 2204 clone. I have seen Lee Jackson do this type of mod and he squeezes the extra tube between V2 and V3 and it is a tight fit!. What are the effects of this proximity and would it be better to move it away from the PI and between V1 and V2?
Title: Re: Preamp tube proximity. marshall mod
Post by: sluckey on March 07, 2022, 02:21:32 pm
I'm sure Lee knows what he was doing. If we could see a schematic we might have a clue too.
Title: Re: Preamp tube proximity. marshall mod
Post by: joesatch on March 07, 2022, 03:43:44 pm
he puts it between v2 and v3 so he can tap off the B+ connected to the V2 100k plate. I'm gonna put mine between v1 and v2, wanna stay away from the phase inverter
Title: Re: Preamp tube proximity. marshall mod
Post by: sluckey on March 07, 2022, 04:16:32 pm
Well, since you ain't gonna show a schematic, I'll take a WAG. I suppose that #36 is gonna add more gain stages to your already high gain 2204. Where you put that tube could be very critical.
Title: Re: Preamp tube proximity. marshall mod
Post by: uki on March 07, 2022, 05:19:36 pm
Hey Joe how about put the extra tube at the edge of the chassis and rewire V1 and V2.

Look the picture, it will look much more neat!!
Title: Re: Preamp tube proximity. marshall mod
Post by: joesatch on March 07, 2022, 07:28:37 pm
Hey Joe how about put the extra tube at the edge of the chassis and rewire V1 and V2.

Look the picture, it will look much more neat!!
I have a small box chassis. cant do that
Title: Re: Preamp tube proximity. marshall mod
Post by: tubenit on March 08, 2022, 05:55:28 am
from ARCHIVES    https://el34world.com/Forum/index.php?topic=17406.0
Title: Re: Preamp tube proximity. marshall mod
Post by: dwinstonwood on March 08, 2022, 08:33:04 am
Thanks for that link tubenit!
[but, add an "h" in front of the URL so that it becomes clickable - https... ]