Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: TIMBO on March 30, 2013, 10:30:52 pm

Title: PLEXI 6V6 With OD
Post by: TIMBO on March 30, 2013, 10:30:52 pm

Hi guy's, Well Hasn't this been a pitta of a build, the Hiwatt Lead is now a plexi  :icon_biggrin: Thinking that it better to stick to a circuit that is more mainstream should any problems arise.  :cussing:

Again using M Huss 6V6 Plexi as my build.

Had no real problems on startup and I like the overall sound  :icon_biggrin:

Again I have hiss at full volume but I think that is OK as full volume it's loud and gets over distorted (8 on the dial is a good level) and has plenty of breakup to be Played with.
I think that there is tweaking that could be done to help with the tone as there is not much change in tone in the TS. I was thinking that the TS in the JP Hiwatt might be tried again and splitting V3 as per schem.

I'm also thinking a master volume may be needed possibly PPIMV

Now the OD, As we have done the OD would slot in just before the PI and works well in this position but after looking at the  Hiwatt lead and the position it is in this has tweaked my interest and to keep it simple by just having a volume control as the idea is just to create a CLIPPING type circuit.

After reading the wizard's take on BOOTSTRAPPING I thought this might be the answer BUT there is always a BIG BUTT and this is way over my pay grade as weather this is what I need to achieve this  :w2:

Any input would be great, thanks  :icon_biggrin:

Title: Re: PLEXI 6V6 With OD
Post by: tubenit on March 31, 2013, 06:28:48 am

I think that will work and could sound good.  Only things I would consider changing are:  1)  change the 220uf to 5uf or 10uf. You'll not be able to benefit from the 220uf anyway  &  2)  change the 100k resistors in the bias to 220k.

I did something sorta kinda similar (at some level) with an OD using a triode & CF here: http://www.el34world.com/Forum/index.php?topic=11261.0 (http://www.el34world.com/Forum/index.php?topic=11261.0)       The clean is different obviously, but it turned out pretty good and the owner really likes it.

There is a sound clip of that OD being used here:  http://www.soundclick.com/player/single_player.cfm?songid=10391428&q=hi&newref=1 (http://www.soundclick.com/player/single_player.cfm?songid=10391428&q=hi&newref=1)

With respect, Tubenit

Title: Re: PLEXI 6V6 With OD
Post by: TIMBO on March 31, 2013, 04:42:31 pm

Thanks T, The change to the bias that you talk of which triode are you talking about ???

Thanks for the link to the DOUBLE C amp,that looks great but I want to keep it simple so I will remove the TONE and put a fixed TRIM.

My thoughts were to put the OD just before V3, but if that doesn't work then I can always slot it in before the PI.
This is what I have come up with.Thanks

Title: Re: PLEXI 6V6 With OD
Post by: tubenit on March 31, 2013, 06:49:33 pm

Quote

My thoughts were to put the OD just before V3,

I've done OD like that before.  It should work fine.

I was referring to the power tubes bias and using 220k instead of 100k

With respect, Tubenit