Recommendations for Dual-Gang Pot for Vol/Gain on Preamp

General discussion area for tube amps.

Moderators: pompeiisneaks, Colossal

Post Reply
PRoper
Posts: 3
Joined: Mon Oct 20, 2014 9:55 pm

Recommendations for Dual-Gang Pot for Vol/Gain on Preamp

Post by PRoper »

Hello all,
I built a single channel amp with the cascaded V1a V1b similar to the 2204 Hi Input. The gain comes on a little early for my taste and thought I might modify it with a dual gang pot that would straddle V1b, in hopes that it would give me a little more sweep for the clean side before starting to break up. One pot for the Vol off the V1a output (normal vol), and the other pot would replace the 470K/470K volatage divider after V1b. Anyone messed with this before and have a good recommendation or schematic to reference or any other suggestions?
User avatar
cbass
Posts: 4401
Joined: Sat Jul 23, 2011 6:17 pm
Location: Between Pomona & Bakersfield

Re: Recommendations for Dual-Gang Pot for Vol/Gain on Preamp

Post by cbass »

Like this¿
You do not have the required permissions to view the files attached to this post.
User avatar
mhartman
Posts: 611
Joined: Sun Jun 15, 2008 5:43 pm

Re: Recommendations for Dual-Gang Pot for Vol/Gain on Preamp

Post by mhartman »

cbass wrote:Like this¿
That's totally what I was thinking. I really like my SD60.
Alan0354
Posts: 65
Joined: Tue Apr 15, 2014 7:15 am

Re: Recommendations for Dual-Gang Pot for Vol/Gain on Preamp

Post by Alan0354 »

If you really want two volume, I would look into a dual pot BUT with separate control for each volume......or two totally separate volume pot. You really get different sound adjusting the two volumes, you can lower the first one and crank up the second, or vise verse. You get different sound.
PRoper
Posts: 3
Joined: Mon Oct 20, 2014 9:55 pm

Re: Recommendations for Dual-Gang Pot for Vol/Gain on Preamp

Post by PRoper »

If I use two separate pots would the second pot work better as a 500K or should I stick with 1M for both? Which works better tone and impedance wise?
PRoper
Posts: 3
Joined: Mon Oct 20, 2014 9:55 pm

Re: Recommendations for Dual-Gang Pot for Vol/Gain on Preamp

Post by PRoper »

cbass wrote:Like this¿
Thank you for the Schematic, on the first 500K Pot you have a 220K in front and a 100K to ground what do these acheive or what is the purpose?
pops
Posts: 160
Joined: Tue Dec 17, 2013 12:27 am
Location: S.W. Wi.

Re: Recommendations for Dual-Gang Pot for Vol/Gain on Preamp

Post by pops »

Look for concentric pots, i have used them several times works well.
The world is a better place just for your smile.
Smokebreak
Posts: 1391
Joined: Tue Dec 18, 2012 5:53 pm
Location: Texas

Re: Recommendations for Dual-Gang Pot for Vol/Gain on Preamp

Post by Smokebreak »

PRoper wrote:
cbass wrote:Like this¿
Thank you for the Schematic, on the first 500K Pot you have a 220K in front and a 100K to ground what do these acheive or what is the purpose?
220k//470p, as well as the 560K//.001 are treble peaking networks. This is what gives Marshall types those upper mids they are known for. IIRC the Naked only has 1 network there. You'll find a typical 470K//470p on Marshall schematics .
The 100k to ground off the first gain pot means the voltage division that pot provides will always be a little hotter than the other gain pot, proportionally speaking.
Post Reply