Skyliner and Classic mid pot question

[greiswig]

This is probably a little bit of a dumb question, but I guess I'm kind of thinking out loud. I'm trying out a push-pull pot to switch mid cap values from Skyliner to Classic. The pot value is also supposed to change, though.

I'm not sure where most people typically run their controls in either tone stack. But suppose for the sake of supposing that the mid pot is designed to be run typically around 12:00, whatever the value is. I think both circuits are supposed to use audio taper pots, although I've seen some with linear tapers.

In a 100kA pot, 12:00 would be around 10k to ground, right? So the Classic tone stack would be designed to run around that value. The Skyliner would operate right around 25k to ground in a 250kA pot.

The Classic, since it takes a broader dip out of the tone and has a lower R to ground, would be a fair amount quieter, right? That seems a little backward to me. And sure enough, when I try it out, the Skyliner is considerably hotter. To even them out, I have to get their R to ground close to the same...within about 5k of each other. Then I can start to tell the character difference between the cap values without the drastic drop in volume.

Does this mirror anyone else's experience?

[ayan]

This is probably a little bit of a dumb question, but I guess I'm kind of thinking out loud. I'm trying out a push-pull pot to switch mid cap values from Skyliner to Classic. The pot value is also supposed to change, though.

I'm not sure where most people typically run their controls in either tone stack. But suppose for the sake of supposing that the mid pot is designed to be run typically around 12:00, whatever the value is. I think both circuits are supposed to use audio taper pots, although I've seen some with linear tapers.

In a 100kA pot, 12:00 would be around 10k to ground, right? So the Classic tone stack would be designed to run around that value. The Skyliner would operate right around 25k to ground in a 250kA pot.

The Classic, since it takes a broader dip out of the tone and has a lower R to ground, would be a fair amount quieter, right? That seems a little backward to me. And sure enough, when I try it out, the Skyliner is considerably hotter. To even them out, I have to get their R to ground close to the same...within about 5k of each other. Then I can start to tell the character difference between the cap values without the drastic drop in volume.

Does this mirror anyone else's experience?

Classic uses a 100KL pot (heritage from the Fender reverb control, I suspect). Halfway up, like everyone sets these things, it gives you 50K to ground. The Skyliner 250KA pot gives you 37.5K to ground if you use an Alpha 15% taper pot. If it were me, I would go with the 250KA pot and turn it up a notch when switching to the .047uF cap.

Gil

[greiswig]

Thanks, Gil!

[Structo]

Yes when I tried the .01uf mid cap I had changed the pot to 250K as well.

I didn't like the .01uf cap so I changed back to the .047uf.

But I left the 250k pot in there mainly because I was lazy.

Works fine.