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Push/Pull for Tone/Bypass

F

floatingaxe

Feb 4, 2010
242
6
The great state of Northern NJ
#1
I did some searching and couldn't find anything to help me so I'm hoping that this is an easy one for somebody.

On my J I have Vol/Blend/Bass-Cut/Treb-Cut.
The bass and treble cuts work great, but having 2 pots in the signal path darkens the tone even when they are all the way up.

I want to replace the tone pots with push/pulls so that down is completely bypassed and up is normal tone control.
This way I can have full bright most of the time, but be able to bring in the bass or treble cut if I want to.
I don't know how to wire the push/pulls to do this.
Thanks.
 
#2
The bass cut control will not darken up the tone because it's in series, and not parallel as the treble cut control is.

The big question is what value are your blend and volume pots? That's where your tone will darken up. If you are using 250K for the blend and volume, you have 83.33K load on the pickups. If you use a 500K blend, you will have 125K load on the pickups, just as you would with two 250K volume controls.

To bypass the treble pot, just wire up the push/pull to disconnect the tone cap when you pull it up.

Before you do all that, disconnect the tone cap from ground to see if it even makes a difference.
 
#3
SGD Lutherie said:
The bass cut control will not darken up the tone because it's in series, and not parallel as the treble cut control is.

The big question is what value are your blend and volume pots? That's where your tone will darken up. If you are using 250K for the blend and volume, you have 83.33K load on the pickups. If you use a 500K blend, you will have 125K load on the pickups, just as you would with two 250K volume controls.

To bypass the treble pot, just wire up the push/pull to disconnect the tone cap when you pull it up.

Before you do all that, disconnect the tone cap from ground to see if it even makes a difference.
Click to expand...

+1 to all of this.
 
#10
5818443127_c4514cb5cc_o.png
 
#11
Thanks.
So this is the tone (treble cut)?
The Signal is my "in", where is my "out"?
Also, don't I need to bridge some of the terminals if I want to bypass the cap in the down position?

So it looks like if you label the switch terminals:
s1 s2
s3 s4
s5 s6
s1 and 3 (up) OR 3 and 5 (down) are connected inside the switch, and 2and 4 OR 4 and 5.
Is that right?
 
#12
floatingaxe said:
Thanks.
So this is the tone (treble cut)?
The Signal is my "in", where is my "out"?
Also, don't I need to bridge some of the terminals if I want to bypass the cap in the down position?

So it looks like if you label the switch terminals:
s1 s2
s3 s4
s5 s6
s1 and 3 (up) OR 3 and 5 (down) are connected inside the switch, and 2and 4 OR 4 and 5.
Is that right?
Click to expand...

The tone control runs parallel to the signal, so the input and output both go to that terminal.

You said down was to be bypassed and up was to be the normal tone control. s1 and s2 are down positions, s5 and s6 are up positions. The grounded terminal should be on the side toward the pot.
 
#15
floatingaxe said:
I think I understand enough to do the bass cut now, if I need help I'll come back.
Click to expand...

Like I said earlier, and Line6Man said, you don't need to do anything to the bass control because it wont change anything.

When bypassed it will be like the control is on 10. The bass control is not causing any change in your tone when on 10, unlike the treble cut control.
 
#17
the bass-cut pot is in parallel with its cap, and wired such that the pot on "10" is shorted. that means it doesn't matter if the pot is 10kΩ or 10MΩ, it still shorts out the cap completely, thus doing nothing.

when you turn it down, it starts to matter, as the higher value the pot, the more it forces the signal to go just through the cap, cutting the bass.

i wouldn't bother with push-pulling the treble cut pot (which is in series with the treble-cut cap); at 500kΩ, it already just about doesn't do anything on "10". go with 1M if you want it to totally have zero effect on "10".
 
#18
walterw said:
i wouldn't bother with push-pulling the treble cut pot (which is in series with the treble-cut cap); at 500kΩ, it already just about doesn't do anything on "10". go with 1M if you want it to totally have zero effect on "10".
Click to expand...

I'm going to have to agree with this.
A 500k tone pot places a pretty high resistance between the signal and cap. You won't hear much difference at all between bypassed and "10." (And I have tried this, personally.)

Tone control bypasses are mainly used with 250k pots, where you can actually hear a difference.

Walter, I'm surprised to hear you suggesting 1M tones. Unless your impedance is really high, they act like on/off switches.
 
#19
true enough.

maybe a 250k no-load would be better, as it would still "switch out" at the top, but have a reasonable sweep through its range.
 
#20
line6man said:
I'm going to have to agree with this.
A 500k tone pot places a pretty high resistance between the signal and cap. You won't hear much difference at all between bypassed and "10." (And I have tried this, personally.)

Tone control bypasses are mainly used with 250k pots, where you can actually hear a difference.

Walter, I'm surprised to hear you suggesting 1M tones. Unless your impedance is really high, they act like on/off switches.
Click to expand...

OK, I'm going to have to hijack my own post then.
This used to be active/passive. The bass and treble controls were just for active mode, no tone control in passive. In passive mode the sound was very nice and bright and clear.
I convert to all passive since I never used the active mode and wanted tone control in passive.
Now with just volume, blend, and tone it's not bright and clear anymore. New 500K CTS volume, same blend pot, 500K tone.
I assumed that the tone, even at 10, was stealing some of my highs, so I thought of this bypass idea.
If it's not the tone pot, then what happened? :crying:
 

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