My Jaguar wiring problem: sending out an SOS

[CIJ]

Looking for some help from the resident wiring experts. I recently modded my Jaguar to achieve two goals: 1) series wiring when both pickup selector switches are in the down position (traditionally the Off position or kill switch), and 2) to make both pickups (plus series plus strangle switch) available in the rhythm circuit as well as the lead circuit. I used this wiring diagram for the series wiring and the four deviations from standard.

Wiring deviations

I got this wired up and all seemed to be functioning as it should be. And for the most part it is. However, two issues have become apparent as I've played around a bit more:

The tone pots are cutting some volume as I roll them off (this occurs on both circuits but most noticeably on the lead circuit). The tone pots are still working as tone pots - I can still roll off high frequencies, and even fully counterclockwise I have signal (ie the volume never drops fully out). But some volume drop is definitely perceptible. It is most noticeable through my fuzz face style pedal: the fuzz cleans up a lot going between 10 and 9 or 8 on the tone pot of the lead circuit. There is a similar but less obvious effect with the tone pot of the rhythm circuit .
Another weird thing is that my lead circuit volume knob cuts all signal between 0 and roughly 3 (on a 0-10 scale). It doesn't take this long for signal to kick in from fully "off" on any of my other guitars). I've no idea if these two issues are related but thought the second point worth mentioning.
I wired the lead and rhythm circuits according to this diagram:
https://photos.app.goo.gl/JDNqxRS3DJDtirQ66

Is this expected behaviour? It doesn't seem like it should be. Any help greatly appreciated.

[GilmourD]

Looking for some help from the resident wiring experts. I recently modded my Jaguar to achieve two goals: 1) series wiring when both pickup selector switches are in the down position (traditionally the Off position or kill switch), and 2) to make both pickups (plus series plus strangle switch) available in the rhythm circuit as well as the lead circuit. I used this wiring diagram for the series wiring and the four deviations from standard.

Wiring deviations

I got this wired up and all seemed to be functioning as it should be. And for the most part it is. However, two issues have become apparent as I've played around a bit more:

The tone pots are cutting some volume as I roll them off (this occurs on both circuits but most noticeably on the lead circuit). The tone pots are still working as tone pots - I can still roll off high frequencies, and even fully counterclockwise I have signal (ie the volume never drops fully out). But some volume drop is definitely perceptible. It is most noticeable through my fuzz face style pedal: the fuzz cleans up a lot going between 10 and 9 or 8 on the tone pot of the lead circuit. There is a similar but less obvious effect with the tone pot of the rhythm circuit .
Another weird thing is that my lead circuit volume knob cuts all signal between 0 and roughly 3 (on a 0-10 scale). It doesn't take this long for signal to kick in from fully "off" on any of my other guitars). I've no idea if these two issues are related but thought the second point worth mentioning.
I wired the lead and rhythm circuits according to this diagram:
https://photos.app.goo.gl/JDNqxRS3DJDtirQ66

Is this expected behaviour? It doesn't seem like it should be. Any help greatly appreciated.

So, that seems to be a Jaguar thing with the tone pot killing some volume.

As far as the volume control basically being "zero" at 3... That sounds like something's weird with the pot. The taper may be non-ideal but you should still have SOMETHING that low.

What pots do you have in the guitar?

[CIJ]

So I've read some posts on other forums of people saying this is normal for a Jag and yet others jumping in to disagree. But even if it is normal behaviour on some Jags, surely it's a wiring choice, meaning an alternative wiring scheme could fix the problem. I mean, it's a problem for me anyway - I absolutely hate it.

I'm led to believe this effect is a feature of 50s wiring, but the wiring diagram I followed above is not 50s wiring - am I correct in that?

I should have said in my original post that I have a treble bleed on the volume pot also, in case that's part of this weird interaction.

[HNB]

Are you using normal fender pots? Some pots do not have the best audio sweep where they seem to cut sound or react mostly between 1-3 while others have a more gradual sweep. Are your cavities shielded? You might have a lug contacting ground and that could make it work like a volume by accident.

[GilmourD]

So I've read some posts on other forums of people saying this is normal for a Jag and yet others jumping in to disagree. But even if it is normal behaviour on some Jags, surely it's a wiring choice, meaning an alternative wiring scheme could fix the problem. I mean, it's a problem for me anyway - I absolutely hate it.

I'm led to believe this effect is a feature of 50s wiring, but the wiring diagram I followed above is not 50s wiring - am I correct in that?

I should have said in my original post that I have a treble bleed on the volume pot also, in case that's part of this weird interaction.

'50s wiring doesn't really apply to Jaguars. Jaguars are Jaguars are Jaguars.

That said, you could always try wiring the lead circuit tone control like a Jazzmaster.

[alexpigment]

You might try removing the resistor from the tone pot as a test. There is debate about its function; many believe it’s a primitive treble bleed, and others say it is part of the strangle switch functionality (but still affects the circuit when the strangle is off). If you’ve got a treble bleed on the volume pot and you’ve also got the 56k resistor, you may be adding too much resistance and to the circuit.

Short of that, I would personally just wire the volume and tone like a normal Jazzmaster/tele as mentioned above, albeit you would be coming in from the rhythm switch to the volume and going out back to the switch (from the middle lug of the volume). That’s really just because I do a lot of wiring work based on experience rather than diagrams, and I don’t fully understand the logic of the lead circuit going into the tone and out from the volume. That’s not a standard practice in most guitars, at least Fenders.

[CIJ]

Are you using normal fender pots? Some pots do not have the best audio sweep where they seem to cut sound or react mostly between 1-3 while others have a more gradual sweep. Are your cavities shielded? You might have a lug contacting ground and that could make it work like a volume by accident.

I'm using CTS audio pots - the ones in this wiring kit, to be specific.
Amazon

I shielded the cavities with copper tape. I don't believe the tone put lugs are in contact with it but it's possible. I'll double-check when I'm back with the guitar.

[CIJ]

So I've read some posts on other forums of people saying this is normal for a Jag and yet others jumping in to disagree. But even if it is normal behaviour on some Jags, surely it's a wiring choice, meaning an alternative wiring scheme could fix the problem. I mean, it's a problem for me anyway - I absolutely hate it.

I'm led to believe this effect is a feature of 50s wiring, but the wiring diagram I followed above is not 50s wiring - am I correct in that?

I should have said in my original post that I have a treble bleed on the volume pot also, in case that's part of this weird interaction.

'50s wiring doesn't really apply to Jaguars. Jaguars are Jaguars are Jaguars.

That said, you could always try wiring the lead circuit tone control like a Jazzmaster.

I thought 50s wiring could be applied to any guitar. I've certainly seen it in relation to Les Pauls, Strats, Teles... Why not potentially Jags? But from what I can tell, my Jag is not wired this way. I am kinda newish to this stuff but have seen it said in other places as a possible explanation for the issue so thought I'd check here.

I'll have to check the difference between this wiring and the JM wiring. I don't know off the top of my head.

[CIJ]

You might try removing the resistor from the tone pot as a test. There is debate about its function; many believe it’s a primitive treble bleed, and others say it is part of the strangle switch functionality (but still affects the circuit when the strangle is off). If you’ve got a treble bleed on the volume pot and you’ve also got the 56k resistor, you may be adding too much resistance and to the circuit.

Short of that, I would personally just wire the volume and tone like a normal Jazzmaster/tele as mentioned above, albeit you would be coming in from the rhythm switch to the volume and going out back to the switch (from the middle lug of the volume). That’s really just because I do a lot of wiring work based on experience rather than diagrams, and I don’t fully understand the logic of the lead circuit going into the tone and out from the volume. That’s not a standard practice in most guitars, at least Fenders.

Some good ideas in here to test out, thanks. I'm a bit unclear what you mean by "the logic of the lead circuit going into the tone and out from the volume". Could you pitch that lower? Which diagram are you referring to here? The partial diagram showing the mods, or the full wiring diagram (the one without the mods)? Thanks for your forbearance!

[alexpigment]

Some good ideas in here to test out, thanks. I'm a bit unclear what you mean by "the logic of the lead circuit going into the tone and out from the volume". Could you pitch that lower? Which diagram are you referring to here? The partial diagram showing the mods, or the full wiring diagram (the one without the mods)? Thanks for your forbearance!

Both of the diagrams, as well as standard Jaguar wiring. It goes from the 3-switch array to the tone, then to the volume, back to the rhythm control switch, and then to the output jack. In most guitars I've wired, the signal usually goes from the pickup selector to the volume, and the volume goes to the output jack (the tone is wired to the volume).

My point was really just to say that I don't understand the logic of why the Jaguar goes to the tone first. That says more about my own knowledge than any design flaw/oddity in the Jaguar, but if I were personally trying to solve this problem, I would do a test where it's wired like a Jazzmaster or Tele or any other number of guitars to weed out any Jaguar-specific oddities with the tone knob. After all, you said that others online claimed that this was "normal" for a standard Jaguar. Again though, I'd try temporarily removing the tone pot's 56k resistor (not the capacitor) before I did anything else.

P.S. I do have a Jaguar, but it was originally an HH model that I gutted it to put single coils in. I did not wire up a rhythm circuit or rewire it to be fully traditional. Just snipped the parts I didn't need and let the wires go where they needed to. The volume/tone wiring is much more similar to a Jazzmaster.

[CIJ]

Some good ideas in here to test out, thanks. I'm a bit unclear what you mean by "the logic of the lead circuit going into the tone and out from the volume". Could you pitch that lower? Which diagram are you referring to here? The partial diagram showing the mods, or the full wiring diagram (the one without the mods)? Thanks for your forbearance!

Both of the diagrams, as well as standard Jaguar wiring. It goes from the 3-switch array to the tone, then to the volume, back to the rhythm control switch, and then to the output jack. In most guitars I've wired, the signal usually goes from the pickup selector to the volume, and the volume goes to the output jack (the tone is wired to the volume).

My point was really just to say that I don't understand the logic of why the Jaguar goes to the tone first. That says more about my own knowledge than any design flaw/oddity in the Jaguar, but if I were personally trying to solve this problem, I would do a test where it's wired like a Jazzmaster or Tele or any other number of guitars to weed out any Jaguar-specific oddities with the tone knob. After all, you said that others online claimed that this was "normal" for a standard Jaguar. Again though, I'd try temporarily removing the tone pot's 56k resistor (not the capacitor) before I did anything else.

P.S. I do have a Jaguar, but it was originally an HH model that I gutted it to put single coils in. I did not wire up a rhythm circuit or rewire it to be fully traditional. Just snipped the parts I didn't need and let the wires go where they needed to. The volume/tone wiring is much more similar to a Jazzmaster.

Okay, thanks for clarifying that for me. I suppose I haven't wired enough guitars to know that that's odd.

I'll check I'm not shorting out a tone lug on the shielding,then remove the resistor and then maybe look at JM wiring.

I was so pleased with myself when I got this Jag wired up and everything seemed to work. First time too! But nah, too good to be true.

I'll report back if I get anywhere.

[MattK]

One thing which can impede understanding is the idea of signal “going in” and “coming out”. If the wire from the pickup selector goes to the top of the volume pot and a wire from that goes to the tone pot, that is exactly the same as the wire from the selector going to the tone pot and a wire connecting that to the volume pot. The wires make everything “equal”. The circuit works by having the pickup voltage at the top of the volume pot and the output jack selecting some part of that pot’s range, from 0% to 100%. The tone pot is connected to the pickup signal and optionally drains some of it away thru another path to ground - except that path has a capacitor in it so only the high frequencies can be drained away.
Once you see it like that, the connections make more sense.

[timtam]

I'll have to check the difference between this wiring and the JM wiring. I don't know off the top of my head.

The jag lead circuit's pots are wired quite differently to a jazzmaster's. Neither use (Gibson-style) "50's wiring".





I also mentioned in my reply to your TGP post the interaction between the tone control and volume in the rhythm circuit (and the Seymour Duncan wiring mod that attempted to address that). The rhythm circuit is wired the same way in jags and jazzmasters.

[CIJ]

One thing which can impede understanding is the idea of signal “going in” and “coming out”. If the wire from the pickup selector goes to the top of the volume pot and a wire from that goes to the tone pot, that is exactly the same as the wire from the selector going to the tone pot and a wire connecting that to the volume pot. The wires make everything “equal”. The circuit works by having the pickup voltage at the top of the volume pot and the output jack selecting some part of that pot’s range, from 0% to 100%. The tone pot is connected to the pickup signal and optionally drains some of it away thru another path to ground - except that path has a capacitor in it so only the high frequencies can be drained away.
Once you see it like that, the connections make more sense.

That's actually really helpful.

[MattK]

Hey great! It took me a long time to understand it that way so I hope it saves you the effort.
That said, I am still trying to get my head around what the 56k is doing in that Jag diagram, I can’t decide if it’s saving some of the high frequencies from the tone pot or somehow increasing the tone pot's effect.