#1
So I have the hot rodded humbucker set in a Les paul with 250k volume pots and tbx's for both the tones. My problem is the jump of brightness in the jb once you get to the 1meg pot on the tbx. I have it wired as such:

Could this be fixed by adding a 220k cap between the 3 lugs on both of the pots to ease the transition? I'm not good with thinking through hypothetical wirings in my head and I need opinions.
#2
Is the point of this TBX setup just to give you different tone filters? I'm not sure how valuable I'd find that, to be honest. Certainly I would consider using another pot value if it were available, I have not found 1M to be a friendly value for the JB. You can always fiddle with the R/C values, but perhaps I'm missing what the point of this mod is. If you're trying to make the transition less bright, aren't you just removing the function of the switch?

This seems like something far more suited to a single-coil guitar than to a JB. Perhaps I've misunderstood but I've done a whole lot of JB mods and this one is not one I'd expect to work well.
#3
That's what I thought too, because the jb can be bright in Gibsons any way and cutting bass would just make it sound brighter. Buy what the mod attempts to do is fix how the stock tbx didn't actually cut bass, all it did was put a resistor to make it sound like it was cutting bass from 6 to 10 when in reality it was just cutting the resistor out of the circuit. Also, does a bass cut make it brighter or just thin your tone out more than anything?
Last edited by christopher0214 at Jul 11, 2016,
#4
The stock 82k resistor loads the pickups and the 6-10 setting would put a variable 1M resistor in series with it to reduce the loading, so technically it did cut bass.

As for the jump in brightness, I think it has to do with the 250k side opening up so I don't think you can do anything about it. It's been years since I've dealt with this stuff on a daily basis so I could be wrong.
#5
Could you add a cap after the 1megs output to add more resistance? My question is still up for if bass cut thins it or more of makes it brighter.
Last edited by christopher0214 at Jul 12, 2016,
#6
It makes it brighter by thinning it out. As the name "bass-cut" suggests, it is cutting out bass frequencies. Nothing is being added, if that's what you're asking.

A cap after the 1M pot will not increase its resistance. I think you mean adding a resistor. The 1M pot and 2n2 cap are in series with the signal, so no, you wouldn't want this.

This is a basic overview of what's going on (note that the TBX pot is special, but the circuit is otherwise the same)

The stuff in black is just a standard tone control, so let's just ignore it. With the 1M pot at full-CW, the 2n2 cap is shorted out and nothing is happening. With the 1M pot at full-CCW rotation, there is a 1M resistor across the 2n2 cap; for this purpose, that resistance is so high that it can be ignored and treated like an open circuit. This means that the 2n2 cap is now in series with the signal. Caps pass high frequencies more easily than low frequencies, so the lows are being blocked and only the highs are making it to the output jack.

If you have the parts, just experiment with it. You'll learn a hell of a lot more and you'll get faster, more definitive answers. That's what the hobby is all about, man.
#7
I guess your right, I just wanted to avoid the hassle of having to buy all these caps and resistors that I'm not going to use. I only am really able to work on one guitar a year so I have all these parts lying around.