Making the series position on a 4-way tele less muddy

[markoplan]

I presently have a telecaster wired with a 4 way switch, as described in this article:

www.premierguitar.com/articles/22357-mod-garage-telecaster-series-wiring

I find the series position to be muddy and therefore not so useful.  That said, I like the idea of having a stronger, fuller lead tone, but the full series position is overkill.  So the question is how do I dial it back a little? 

The idea I had was wiring a small resistor (e.g. 2k) into the series linkage between the two sides of the switch (i.e., with one side of the resistor connector to the series link, and one side connected to ground).  I was inspired by the partial coil split PRS uses on its humbuckers (i.e., stronger than a full coil split, sweeter than a full HB).  

Will this placement of a resistor do what i expect, without affecting the other switching positions? Has anyone tried something like this in a tele?  Any thoughts on whether a cap (or cap and a resistor combined) would be a better choice than a resistor alone?  

[thetragichero]

can you disconnect the tone pot while in series mode?

[markoplan]

the tone pot is no-load

[thetragichero]

hmm have you tried a larger volume pot?
easy test is replacing the volume pot's connection to ground with a 220k or 270k resistor
won't work if you're using the back of the pot as a ground point but otherwise should tell you if a 500k pot would suit your needs

[Yogi B]

Aug 9, 2020 11:18:50 GMT -5 markoplan said:

The idea I had was wiring a small resistor (e.g. 2k) into the series linkage between the two sides of the switch (i.e., with one side of the resistor connector to the series link, and one side connected to ground). I was inspired by the partial coil split PRS uses on its humbuckers (i.e., stronger than a full coil split, sweeter than a full HB).

Will this placement of a resistor do what i expect, without affecting the other switching positions?

Since the series link is disconnected from the pickups in all but the series position it won't affect the the other positions, but whether it will do what you expect very much depends on what you expect.

The most important thing to note is that partially bypassing a coil (the bridge pickup, based on the diagram you linked, and your intention to connect the resistor between the series link & ground) will reduce the output from that coil. This isn't much of an issue when performing a partial coil split on a humbucker as, being in very close proximity, the two coils will sound very similar. However, in your case this would mean that series tone shall no longer be a 50/50 mix of neck and bridge, but will tend towards sounding more similar to the neck pickup.

More specifically in terms of frequency response partially bypassing one of the two coils in this manner can be thought of providing a lower impedance path for the treble frequencies of the non-bypassed coil (currently the neck pickup), while increasing the load and thereby decreasing the treble frequency output of the bypassed coil (currently the bridge pickup).

In real terms the result is like taking the normal, single-coil, output of the neck pickup and adding in some of the bass frequency output of the bridge pickup. Sometimes this is what people want, a tonal variation close to one of their pickups with some extra low-end output, but preserving the 'delicate' top-end of a single coil. That might be you, but there is an alternative that more closely aligns with the idea of taking 'dialling back' a series tone.

The alternative is to replace the series link with a resistor & capacitor in parallel (e.g. an 82k resistor in parallel with a 1n cap), this means that at full volume the series setting will behave as tough it is connected to a 330k volume pot with treble bleed dialled down a little, to about 8¹/₂, (assuming your current volume is 250k and we're thinking in terms of log tapers).

[JohnH]

Yogi is on the right lines.

Ive played with this issue is a few ways in my own guitars, but based around series wiring for Strats.

Putting more things in series may just choke the sound in a bad way, but partly bypassing one coil is a good way to go. The idea is to bypass one coil with ether a cap or a resistor. This can be a fixed setting or you can use a pot. The decisions to be made are which pickup to bypass, and with what component and of what value.

If you wired using the Fender diagram that D Wacker purloined for his post, then the bridge pickup is permanently grounded and the neck pickup has its black wire usually grounded but it connects to the bridge hot in series mode. So without a general wiring do-over, this is best set up for part bypassing the bridge pickup in series mode.

Options:

1. Put a cap between the black neck wire and ground, value in the range 22, 47 or 82 nF (=0.022uF, 0.047uF, 0.082uF) . This does the trick of letting more single-coil treble from neck run through, using the bridge pickup to provide a mid boost

2. Same idea, using a resistor, probably somewhere between 5k and 20k

3. This one, on my Strat, is my favorite ever wiring mod in 15 years. But it means repurposing your tone pot as a series blender (on the Strat I still have another pot for tone). again, wiring between the neck black wire and ground, wire the tone pot, using the same two lugs as usual. Now you can start with a fully bypassed connection giving you simple neck pickup, and fade in the bridge, bringing up the mids and volume as it does. I find I like it at a about 3 on the pot, which is probably about 10k.

Since this idea is easy to try needing no new parts, you could do it temporarily to explore. Then, when you find the best pot setting, disconnect it and measure the pot to help pic a fixed resistor to use in 2. Or you might enjoy the blender control, as I do

4. Moving on, you can use a normal tone pot, adding another 0.047 cap, which goes to the third tone lug. Minor pot rewiring needed (needs a diagram to explain). In normal modes, its no change, in series mode, at 10 on the tone pot it creates condition 1 above for a brighter series tone, as you fade the tone down, it smoothly transitions through full series down to muted series. I also did this one on a Strat and it works. But, it may not work with a no-load tone pot, if you bought one. If you made your no-load from a standard pot, then it should work, with the cap setting at 10 being a sudden transition.

5. Totally different. Take a look at what Phostenix did with a TBX pot (see our Phostenix pages). He made this one control into a master bass-cut/no-load/treble cut. You could add that as a master control in place of the tone pot.

[reTrEaD]

As Yogi and John indicated, there are a number of different solutions. Personally, I favor one where one of the pickups has a capacitor in parallel with it, only in the series position. I'd favor making that the neck pickup so the high-frequency content of the bridge pickup can bypass the internal inductance of the neck pickup.

If you're using a 4-way switch, depending upon how it is wired, the modification could be very simple. Just add the blue capacitor (22nF would be a reasonable value) with the red wires.



If you're using a different wiring and supply the diagram you're using, we can modify it to accomplish the same goal.

[markoplan]

thanks for the great feedback

my tone control on this guitar is already a modified TBX bass cut/no load/treble cut.  JohnH's suggestion #4 seems similar to the Peavey T-60 wiring from back in the 70's.  I've always thought that was brilliant, but here i'd like to keep the modified TBX control, and i'm concerned that with only 1/2 the usual rotation to work with, i will be harder to dial-in the desired tone. And because this is a tele, i don't have room for a separate series blender pot.  In any case, i'd like to have something preset that i can switch to on the fly, so suggestions ##1 and 2 are the most appealing to me. (#2 is what I was trying to describe in my original post, except with a larger resistor, correct?)  

you've also encouraged me to think about whether i should be reworking the switch to have the neck pickup hardwired to ground (rather than the bridge), because my goal here is a slightly stronger bridge pickup tone (not a stronger neck pickup tone).  i'm already planning to change this to a 5P2T (to add a parallel HOoP position), so i'm going to rewire the whole switch anyway.  So while i'm at it, I could change which pickup goes first in the series.  Any thoughts about this approach, in conjunction with # 1 or #2?  if i use #1, what is the general principle regarding cap value?  (e.g., bigger cap = more shunted to ground and therefore more like a single coil by itself?)

[markoplan]

reTrEaD, thank you.  our messages crossed -- i didn't see your post before sending the next one.  sorry about that.  i will review.

[JohnH]

It sounds like its settling down to a system where you bypass one coil with an R or a C.

A nice advantage of Teles over Strats is that you can pull the wiring and controls out but still keep the guitar strung up for testing.

If, based on your first post diagram, you connect the cap or resistor to the neck black wire, you can connect its other end to ground to try bypassing the bridge. Or connect it to the outer hot volume lug to try bypassing the neck. This could let you test a range of component choices. If bridge bypassed is chosen then you can wire it straight in. If neck bypassed is chosen, then it would need rewiring to make neck the gounded one, so that the other combos work properly.

[ashcatlt]

So anyway the schemes in this thread so far are based on standard 4-way Baja wiring, which leaves the neck pickup hanging from hot in the bridge-only position. We can argue for a while whether that’s better than shorting it, but if you’d rather short it, sumgai has a scheme around here somewhere that shows how to do it.

[sumgai]

Aug 11, 2020 11:20:37 GMT -5 ashcatlt said:

.... if you’d rather short it, sumgai has a scheme around here somewhere that shows how to do it.

That would be this one:




The previously posted version, in a separate thread, is now imprinted with the PhotoBucket "naughty little user" logo, so I decided to re-upload with a fresh copy, courtesy of Postimage.