Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Esquirefreak on October 10, 2022, 09:26:03 am

Title: A250k solid shaft push/pull pot
Post by: Esquirefreak on October 10, 2022, 09:26:03 am
Does anyone here know where to find good quality p/p 250k pots with steel/brass/metal solid shafts? Looks like most pots are either splined shafts or concentric dual gang pots. At least, here in Europe, that is.

I've been experimenting with treble attenuation and would like to have this option on a switch. Two series caps with the switch between them would hopefully avoid DC presens and increase the switch longevity.

This in combination with a 47pF bright cap on the volume pot makes for interesting combinations, because the high mids get scooped out a bit.

/Max
Title: Re: A250k solid shaft push/pull pot
Post by: PRR on October 10, 2022, 01:11:23 pm
That's still going to pop. Leaving the ends of caps floating is such an undefined (bad idea) state that my circuit simulator won't even think about it.

I think what you want is this.
Title: Re: A250k solid shaft push/pull pot
Post by: isaac_teller on October 10, 2022, 02:42:56 pm
https://www.tubesandmore.com/products/potentiometer-alpha-linear-solid-dpdt-7mm-bushing

Title: Re: A250k solid shaft push/pull pot
Post by: Esquirefreak on October 10, 2022, 04:57:23 pm
That's still going to pop. Leaving the ends of caps floating is such an undefined (bad idea) state that my circuit simulator won't even think about it.

I think what you want is this.

Of course, that makes sense. Thanks!

/Max