Master Volume pot

[Roe]

Martin, just found this PPIMV for JTM45, I assume it will work equally well for the 100W Super Lead.

Ange

It works better on the latter due to less nfb

[jazzbass]

No I don't do much amp stuff anymore because of many health issues including my left ear finally decided it was tired and with years of multiple surgeries. It goes from no hearing to slight, ENT don't know what exactly is wrong.

The right ear is completely swollen shut with an infection but can't get back to ENT to get that fixed.

The tinnitus has increased dramatically too so for me to rely on my hearing to tune amps would be a joke.

Trying not to be too funny

Hi Mark,

I was looking in TAG for insights into Ken Fisher's amps and only now reading what you wrote in 2015.
I really hope you have solved those hearing problems, they are serious problems for everyone but especially for musicians.
many good wishes

Franco

[M Fowler]

Wow I read what I wrote and yes the ears are better but hearing is muffled.

Been doing little amp stuff since we moved, no room and little energy. But still have the desire to build.
Perhaps lumber price will drop and get a shop built.

Mark

[jazzbass]

Wow I read what I wrote and yes the ears are better but hearing is muffled.

Been doing little amp stuff since we moved, no room and little energy. But still have the desire to build.
Perhaps lumber price will drop and get a shop built.

Mark

Hi Mark,
wikipedia writes that the country you live in has 189 inhabitants, wow, it's really very small and I guess you all know each other. I live in Resana (TV) a town in northern Italy. Resana has 4500 inhabitants but a few chilometers away I have four large cities, Venice, Padua, Vicenza, Treviso.
I hope you can build the shop you want soon and I am pleased to read that your hearing is getting better.
I wish you every luck.
Franco

[M Fowler]

Thanks Franco, I love small communities, no hassle or problems.

Mark

[Ledvedder5150]

Sorry, I realize this is an old thread. But I'm thinking of trying a ppimv in my Liverpool build. I'm curious if any has had decent results. I do use a power station attenuator, but thought it might be useful to also have the ppimv option in a pinch. Where do they sell 3/8" 250K linear dual pots? Also, I read somewhere that it's useful to add a cut control to adjust when using the ppimv? Where is this documentation?

[sluckey]

https://www.tubesandmore.com/products/p ... 5c147a1052

[martin manning]

I don't know where you are loaded but Amplified Parts has dual 250k Audio pots. https://www.amplifiedparts.com/products ... audio-dual
Classic Vox cut control is just a 250k linear pot wired as a variable resistance in series with a 2n2 cap across the output tube grids, just before the grid stoppers.

[Ledvedder5150]

I don't know where you are loaded but Amplified Parts has dual 250k Audio pots. https://www.amplifiedparts.com/products ... audio-dual
Classic Vox cut control is just a 260k linear pot wired as a variable resistance in series with a 2n2 cap across the output tube grids, just before the grid stoppers.

It seems most are saying a dual 250k linear works better as a ppimv. And I thought the cut control uses 250k audio?

[martin manning]

The 250k pot elements are replacing the 220k grid leak resistors, so 250k is the closest value, and then when you add a 2M2 safety resistor the effective value is 224k (if the pots are really 250k). AC30 seems to have a log pot for the cut, but my Express has a linear, which works well.

[Ledvedder5150]

Has anyone had good results with one in a Liverpool or Express?

[martin manning]

The PPIMV? Yes, my express has one, and it works well.

[Ledvedder5150]

The PPIMV? Yes, my express has one, and it works well.

Do you have a cut control as well?

[martin manning]

Yes, that is how I learned that the cut compliments the PPIMV.

[Ledvedder5150]

Yes, that is how I learned that the cut compliments the PPIMV.

I'm assuming it's similar to this setup?

Screenshot_20230117_125737_Gallery.jpg