Nate Dort wrote: Thu Jul 13, 2023 12:30 pm

bassdriver wrote: Thu Jul 13, 2023 12:25 pm Oh and maybe a master volume right before the output might be a nice feature. Wouldn’t that allow you to drive the tubes into saturation and then reduce the output level accordingly?

Yeah, I have a master volume on my Gyraf G9 clone and being able to drive the tubes hard is where the fun is.

I guess I should try this with my Mila preamp too! Is it as simple as inserting a potentiometer right in front of the output transformer and dropping the signal to ground?

bassdriver wrote: Fri Jul 14, 2023 12:08 pm

Nate Dort wrote: Thu Jul 13, 2023 12:30 pm

bassdriver wrote: Thu Jul 13, 2023 12:25 pm Oh and maybe a master volume right before the output might be a nice feature. Wouldn’t that allow you to drive the tubes into saturation and then reduce the output level accordingly?

Yeah, I have a master volume on my Gyraf G9 clone and being able to drive the tubes hard is where the fun is.

I guess I should try this with my Mila preamp too! Is it as simple as inserting a potentiometer right in front of the output transformer and dropping the signal to ground?

You'll need some sort of buffer stage to present the correct impedance to the transformer primary, like this:

The input pad i'm using, as suggested here is this:


Looking at it struck me how similar it was to what Ken Fischer dubbed the "Master Volume Type 3". Basically a post-phase inverter variable resistor that allowed blending of the two phase-inverted signals to cancel each other out. Kinda like a Vox "cut" control but no cap. Like so:



One wonders if you couldnt do the same sort of approach on the secondaries of the output transformer to achieve a passive output reduction?

Nate Dort wrote: Sat Jul 15, 2023 6:13 am You'll need some sort of buffer stage to present the correct impedance to the transformer primary, like this:

Thanks, I googled the gyraf schematic last night and figured it might be way more complex than I imagined!

Dr Tony Balls wrote: Sat Jul 15, 2023 6:34 am The input pad i'm using, as suggested here is this:

Looking at it struck me how similar it was to what Ken Fischer dubbed the "Master Volume Type 3". Basically a post-phase inverter variable resistor that allowed blending of the two phase-inverted signals to cancel each other out. Kinda like a Vox "cut" control but no cap. Like so:
One wonders if you couldnt do the same sort of approach on the secondaries of the output transformer to achieve a passive output reduction?

The pad on the left looks pretty much like the pad in the Mila design, just with a 3 way switch and slightly different resistors.
I too been wondering if blending the +/- signal post output transformer would work!

Powerful Booster. Direct clone of the 18V Colorsound Power Booster. A while ago I made a limited run of these for Tommy's Guitar in Everett, WA. The customer had one of those original ones and wanted a second one.

Dr Tony Balls wrote: Thu Aug 17, 2023 12:59 pm Powerful Booster. Direct clone of the 18V Colorsound Power Booster. A while ago I made a limited run of these for Tommy's Guitar in Everett, WA. The customer had one of those original ones and wanted a second one.

Nice. I’ll be honest I don’t much like the master volume mod that other people add to these. The only caveat is that you do get a gnarly fuzz with the gain maxed and master down. But all the in between sounds just don’t do it for me.

Dr Tony Balls wrote: Thu Aug 17, 2023 12:59 pm Powerful Booster. Direct clone of the 18V Colorsound Power Booster. A while ago I made a limited run of these for Tommy's Guitar in Everett, WA. The customer had one of those original ones and wanted a second one.

I bought one of those from the original run, sold it, and had you make me another one too. I still have the second one. Those are killer pedals

Splitter to serve FM GuyLaCroix's needs per this post: viewtopic.php?p=823904#p823904

3-way buffered split with phase flip and ground lift on two channels.

Looks great!