Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Ledvedder on August 11, 2022, 12:03:43 pm

Title: Dual PPIMV? Anyone?
Post by: Ledvedder on August 11, 2022, 12:03:43 pm

Has anyone done this to a 1987/1959 circuit? If so, I'm wondering how it works, and hopefully get more information about it. I have a PPIMV in my 1987 build that works pretty well, but I'd love to have dual switchable ones.

http://forum.metropoulos.net/viewtopic.php?t=45431

Title: Re: Dual PPIMV? Anyone?
Post by: kagliostro on August 11, 2022, 05:04:55 pm

Never tried

But I don't see a reason to don't give a try

you can do all trying without mod to the faceplate and using a DPDT Switch

Then, if you are satisfied you can go on with the necessary faceplate mod

Our friend Da Geezer experimented something like that in one amp (don't remember which kind of amp)

Franco


p.s.: May be a relay and the use of a FS will result more performant instead of a panel switch

Title: Re: Dual PPIMV? Anyone?
Post by: acheld on August 11, 2022, 06:18:31 pm

This may or may not be relevant, but Dumble included a "trim" pot for the LTP in the #124 and others -- this varied the plate resistance in lieu of the usual Fender 82K/100K.  One had to adjust the the trim pot to the "optimal" tone using an arcane (to me) method.  Wouldn't a dual PPIMV do the same?