Please Help With Strange Wiring In '72 Custom - Advice Needed On Best Alternative Please

BluegrassPicker

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Regarding vol/tone independance, Fralin’s and Modern (Gibson style) and your diagram all seem equivalent to me.

Do you like what you hear now? If yes, change nothing. If no, then switch to the wiring you like, but tonewise it’s the choice of tone caps and pots values that is paramount.
I definitely like what I hear now, except for the muddy sounding RI WRHB that's getting replaced in this process.

The problem is while I'm going through the effort to do the HB installation I'd like to make all the components and wiring correct or as "optimal" as can be, or as good as what is generally thought to be correct on the average. I'm trying to prevent having to re-do it later after I find that I did the wrong thing. I don't have the Tele expertise to know one method of wiring from the other or if what I have now is good or bad, hence my reaching out to the Tele folks here, and the responses have been very helpful and I'm learning a lot in the process.
 

NoTeleBob

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snip

Me neither. Sure the vol and tone pots value affect the tone, and the way it is wired may have some effect too. That’s what I hear with my Esquire when switching from position 2 (Vol+tone, tone to 10) to position 1 (Vol only, tone bypassed): Noticeable gain in the highs.
Regarding the 50s vs Modern wiring, it is a thing, but I have never been able to do a fair comparison. I have guitars wired both ways though, but my feeling is that the difference is subtle compared to other factors (pickups, tone cap and pots values).
This is why I chose to emphasize here the more practical question of the volume wiring over the more subtle effect of the tone wiring.

The pickup is an inductor and the pot a resistor, so it forms a filter - and RL network. The volume pot acts to restrict that high-end filtering. The more resistance, the more it stops the bleed to ground through the pot. That's why we use a 500K pot with a humbucker (dark, it needs all the highs it can muster) vs. a single coil (brighter, we can afford to lose a little and probably even want to).

The tone control is an RC filter. The highs pass through the capacitor. The pot resists that flow. But it lets some through. If you use a higher value pot, you will again keep more highs. Once again, we probably want a 500K with a humbucker.

But, it's all a bit complicated based on the inductance in the coil, the other components, and other factors well beyond my simple analysis. Whether a 250K vs. 500K or a no-load tone and/or volume make any difference in output or tone output is all very much dependent on those other components in the circuit all interacting. Add another pickup, and a cable to the amp, and it's all a bit complicated. Most people solve it with trial and error.

In the OP's case we've also added a treble bleed. It will interact with the resistance in the pot. As the pot (wiper to output) resistance increases beyond the value of the resistor in the treble-bleed, more signal is forced through the small capacitor in the bleed. the small value of the capacitor make it essentially a bass filter, which means that treble is effectively increase. So, turn the pot closer to "10" and the resistance from wiper to output is low, little goes through the treble bleed. Turn down towards "1" and more signal runs through the cap and treble is effectively increased.

That 1 meg volume pot in the OP's wiring is certainly limiting any bleed of treble to ground. But I think that it also reduces the point at which the treble bleed comes into play. So you conversely lose treble over more of the volume control's range. But I'm no expert.

Whether the crossed wiring of the pot in the OP's diagram matters... i don't think so. You've still got a voltage divider (the pot and the wiper). It's just backwards. But, there might be some subtle effect beyond my rudimentary understanding of a voltage divider.

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NoTeleBob

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What value tone pot would you put on the WRHB if it were yours?

I'm not sure how to wire master tone or bass controls as I have no diagram to refer to. Do you have a link to an example? Thanks.

Cutting the bleeds would be the easy part.

Sorry, didn't get to drawing anything. Long day I will do that and post it.
 

jvin248

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I'd pull the control circuit you have in one piece and then start from scratch wiring up the new way you want. That way you can go back or not carry over issues to mods.

.
 

NoTeleBob

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@BluegrassPicker : Sorry for the delay. I found a diagram and tweaked it for your specific situation.

Note that the bass contour cap is probably best as a value between .001 and .003 uf. The smaller the value the more bass it filters out. Since the contour control lets you essentially bypass the filter, I'd probably go on the low side with a .001 or .0015.

1668458317680.png
 

Steve Holt

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When the switch is in middle position (two pickups in parallel) if you turn one volume down it sends the signal from that pickup to ground, so it takes that pickup out of the circuit without affecting the other pickup. Whereas with the more traditional Fender/Fralin wiring, turning one volume down would send the output of both pickups to ground (remember they are in parallel) and silence the two pickups, same as creating a short between the ring and tip of the output Jack…

I have been experimenting on this and made a simplified diagram (no switch , no tone) to help myself understand what happens when the pickups are connected to the center lug of a volume pot:
View attachment 1050107



Me neither. Sure the vol and tone pots value affect the tone, and the way it is wired may have some effect too. That’s what I hear with my Esquire when switching from position 2 (Vol+tone, tone to 10) to position 1 (Vol only, tone bypassed): Noticeable gain in the highs.
Regarding the 50s vs Modern wiring, it is a thing, but I have never been able to do a fair comparison. I have guitars wired both ways though, but my feeling is that the difference is subtle compared to other factors (pickups, tone cap and pots values).
This is why I chose to emphasize here the more practical question of the volume wiring over the more subtle effect of the tone wiring.

That makes sense! I had been wondering why jazz basses were wired that way. That makes sense...now I'm going to have to rewire the bass I did and switch the output and inputs on those!
 

BluegrassPicker

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Pacific NW - USA
@BluegrassPicker : Sorry for the delay. I found a diagram and tweaked it for your specific situation.

Note that the bass contour cap is probably best as a value between .001 and .003 uf. The smaller the value the more bass it filters out. Since the contour control lets you essentially bypass the filter, I'd probably go on the low side with a .001 or .0015.

View attachment 1050999
Thanks for the diagram, much appreciated.
 




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