Silverface vs Blackface BASS control

[Groover]

I have had the experience that on most SF Fenders the BASS control makes no further change from 5 up, where on many BF amps you can hear the control continuing to affect the tone through more of the top half of the pot rotation.

Have others noticed this? and opined about the reasons and/or causes?

The circuits look the same in relevant respects as far as I can tell. Could there really have been a widespread change in the taper of pots at that time of transition?

[Chuck H]

You'd have to spec models to get an accurate response on whether the taper on the bass pot was different. FWIW I don't really know. But I do know that there was NO difference in the bass pot between early SF and late BF amps. But if your talking about an AB763 Amp compared to, say, a Bassman 100 then the difference could be profound. SF to BF is not enough distinction.

Chuck

[Sweetfinger]

I haven't noticed this. Are you sure you're comparing the same value tonestacks? These days you'd have to look inside to be sure- so many fenders have been modded and recapped.

[Groover]

I have not collected any specific measurements or anything, but it seems to be my general across the board impression over a lot of years with a lot of amps. It has seemed so consistently the case that I am surprised no one has chimed in on this thread who has noticed the same thing.

[mbratch]

Many of the amps the circuit hasn't changed from BF to SF. I've had both BF and SF Princeton Reverbs and they bass response is basically the same.

There are lots of factors, though, including speaker, etc, that can impact the bass response. To draw any conclusions you'd really want to do some kind of apples to apples comparison.

[pdf64]

The bass control at the tone stack stayed pretty much the same (some Supers used 0.022 or 0.033uF to the mid control, rather than 0.047uF, and this gives more upper bass).
The difference tends to be the PI input coupling cap, BF tend to use 0.001uF, SF use 0.01uF. My feeling is that with the SF, there's so much more bass from this that it doesn't sound like it increases much, from halfway to max. Even though the control is working the same.

[RWood]

I had a situation like that with a 6G6 bass channel circuit. Different circuit than yours but using Duncan's Tone Stack Calculator really helped me dial it in so that it did exactly what I wanted it to do.

It enables you to skip a lot of trial and error and zoom in on just the compenent values that you need to change.