Help: ES-1F Wiring Mod (phase and series/parallel)

Hi All.

I'm about to start an ES-1F build with my son (diary to launch shortly) and am having trouble finding a wiring diagram to accomplish something which I thought would be fairly straightforward. That is:

1. Neck Volume push/pull to put neck pickup out of phase
2. Bridge Volume push/pull to put both neck and bridge pickups in series (with each other)

I'm not seeking to do any coil splitting, or changing parallel/series configuration within any humbucker.

I have purchased ToneRider Alnico II Classic pickups with 4 conductor wiring.

I found one wiring diagram, but it seems to be for two single coil pickups.
Attachment 44478

If anyone has a wiring diagram to accomplish this (with 50s wiring), I would be most grateful!

Mathew

The diagram is basically just the same, just with different pickup wire colours. In that diagram, white is the ‘hot’ signal from the pickup, black is the ground. For the Toneriders, red is ‘hot’, green is ground. The black and white wires stay connected to each other and to nothing else, so leave the black heat shrink on them.

For each pickup, the exposed shield wire goes to the back of a pot. You don’t connect it to the green wire as you would for a basic 2 vol/2 tone arrangement.

I will say now that two humbuckers in series will sound a hot dull mess. With single coils, you can do it to get more output and a thicker, less bright tone. But compared to single coils you are already starting out with a thicker, less bright tone. You double up the pickups’ inductance when wiring in series, so the resonant peak is moved further down the frequency range and you loose all your treble and gain a lot more low mids. It’s why you aren’t finding series wiring diagrams for humbuckers and its not a feature on other guitars. At best it would be a speciality tone that you use once in a blue moon, but not for everyday use.

Thanks Simon.

I think I can map the diagram across to Toneriders from your clear explanation. Putting the exposed shield wire to the back of a pot; connecting the black and white wires together and heat-shrinking them unconnected to anything; and running the remaining red 'hot' and green ground as per the diagram; all makes sense to me. Thank you for your clear explanation.

I understand what you're saying about tone. In-series is generally pretty useless because it's too dark; and out of phase is generally pretty useless because it's too thin. Intent is to combine the two for a cutting lead sound in bespoke situations.

If anyone else has a better wiring diagram, feel free to chime in. Otherwise, I'll wire IAW the diagram earlier in this thread.

The Toneriders should come with the black and white wires pre-soldered and heatshrinked. I’ve just put some of their Alnico IVs in a guitar and that’s how they came. I just wish their leads were a bit longer as I had to extend one of them to fit in an ES-1.

Technically it’s ‘polarity reversal’ rather than ‘out of phase’. It’s not ‘too thin’ a sound on humbuckers to be useful, or we wouldn’t have classics like ‘Need your love so bad’, though IMO it is too thin on single coils to be anything other than a special effect.

I don’t think you’ll get a ‘better’ wiring diagram. All wiring diagrams tend to use colour codes for a particular manufacturer and you have to swap the colours over for other manufacturers’ pickups.

Let us know what it sounds like!

Thanks, Simon.

Indeed, this is a bit of an experiment, but I'll let you know how it sounds. ‘Need your love so bad’ is a gorgeous sound - so if it's only usefulness is 'polarity reversed' humbuckers, I'll still be delighted.

Build diary to commence shortly!

I now remember that I had a Kent Armstrong Hot Motherbucker in an Ibanez RG. Four thin single coils in one pickup. A mate of mine always uses the ‘cool’ version as the bridge pickup in his guitars. He put it in for me and it was wired as either two humbuckers in series or in parallel. The series mode was very dull and flat sounding to me, parallel was much better and clearer. The DCR was around 28k, so even parallel mode was hot enough to overdrive a clean channel. I took it out after a while and put some (better than the original) Ibanez pickups back in.

Interesting to hear what the polarity-reversed series mode sounds like. As each pickup is hum-cancelling, you don’t have any hum issues. But you still get the doubled inductance, so it won’t sound as bright as a single humbucker. But overdrive/distortion will add a lot of upper harmonics back in.

It looks like series mode bypasses the neck volume control, so only the bridge one works in that mode, so if you select just the neck pickup you’ll get silence. Which is a good thing in a way, as if both volumes were connected, you’d get the equivalent of a 250k volume pot resistance to ground, which would knock-off even more treble.

As usual, Simon has covered all the important stuff about running humbuckers in series. The only thing I'd add is that Mathew also wants to use vintage tone wiring which complicates it further as you have your tone pots hanging off the output side of the volumes, so they are essentially connected directly to the 3-way... so volume and tone combinations impact all throughout the circuit(s).

Anyway, I promised Mathew some diagrams, so here they are.

All of them use vintage tone wiring and each does things slightly differently, so the switching options and effects of the pots varies. Note: all the diagrams were done in a bit of a rush so there may well be some glaring issues that I've missed or messed up, so use at your own risk.


These first two are a standard style and use the spare side of the series push/pull to switch either the input or output from the Bridge volume. This gives a 'mute' position when the Bridge is selected in series mode, and all pots remain connected in some way.

Option: 1
Attachment 44535
The output from the Bridge volume is disconnected from the 3-way toggle when in series mode, but the Bridge volume and tone will still have an effect in the middle and neck positions as they are connected to the Bridge pickup.

Option 2:
Attachment 44536
On this one the Bridge volume input (the Bridge pickup) is disconnected from the pot in series mode, but as the vintage tone is on the output side it still has an effect when the Bridge pup is part of the circuit. And, the volume setting affects how much the tone pot works so there is still a lot of interaction.

Option 3:
Attachment 44537
The above variant swaps things around by having the phase on the Bridge rather than the Neck, and feeding the Neck into the Bridge pickup when in series mode. Also, as it doesn't do any switching on the volumes, you have sound in all positions in series mode. The downside being all pots in circuit and the tones will both be having effects.

Option: weird
This last diagram is a little more experimental, and I don't think I've seen this type of switching used for this sort of layout. Essentially, the Bridge volume and tone pots are wired to share a path to ground and this gets disconnected when you switch to 'series mode'. This disables the Bridge tone control completely and changes the Bridge volume from a voltage divider to a variable resistor. The advantage of this is that you only have the Neck volume and tone as a path to ground in the circuit, which should help to retain more of the highs, and the Bridge 'variable resistor' can tweak some of the sounds (slightly).

In the bridge position in series mode turning down the Bridge volume from '10' will increase the resistance between the Bridge pickup and the output. This should reduce the volume a little and thin out some of the lower frequencies as the resistance will affect them more (in theory).

In the middle position in series mode the Bridge volume 'variable resistor' will be in parallel with the Neck pickup in series with the Bridge. At '10' the Neck pickup gets shorted out and you just get the sound of the Bridge. However, as you turn down the volume it will increase the resistance between the Bridge+ and the 3-way toggle, which causes some of the Bridge signal to go in series through the Neck and some to bypass it via the resistance path. This gives you *some* slight ability to fade the Neck in series with the Bridge. But, it is only limited and will probably be more 'switchy' than expected with all Bridge at '10' and then a lot of Neck almost as soon as you start turning down... so don't have your hopes set too high.

Attachment 44538

I tested the above layout the other day and it seemed to work pretty well, but it was a rough test so your mileage will most likely vary.

Also, remember that you're got to stuff your wiring into the ES through the F-holes... which isn't easy even with simple wiring. That's why I've drawn them with the jack connecting to the switch and then branching to the volumes/tones. If you use shielded wire for your jack-switch connection and then shield links from the switch to the pots, it will help keep things quiet and hopefully allow you to manipulate them more easily. Getting the jack then switch into the body and then making your pickup connections to the push/pulls one are a time may make the process safer and easier... with less screaming and throwing of things when wires break off.

Good luck and ask questions if you have them.

There is one other possibility I should mention, but it only applies if you want a single fixed series configuration with one pickup out of phase(polarity).

If this is the case, the you could replace the two push/pull pots with a single Fender S1 pot. The S1 is a 4-pole push/push pot… so with one button press you could disconnect the bridge volume and tone, bypass the 3-way toggle, reverse the Bridge pickup and link it in series to the Neck pickup and have that go through the Neck volume and tone as master controls direct to the output. Press the button again and it would be back to normal.

But there are caveats:
1. The S1 only has ~9.5mm of thread length, so it would be borderline to get a washer and nut on it through the top of the ES.
2. The S1 uses a specific type of 2-part knob, so your style choices are limited.
3. The S1 is a deep body full sized pot, ~24mm diameter, so it’s probably 4-5mm wider than you can fit through an ES f-hole. And, you can’t squeeze it through sideways like a normal pot. So the only way to fit it would be to cut an access hole in the back of the body, reinforce it, and make a cavity cover so you can feed the wiring in from the back. Difficult, but not impossible.

It’s an option, but not something I’d recommend unless you’re really determined.

Having just wired some full sized-pots with medium length shafts into an ES-1, I’m pretty sure a short-shaft pot wouldn’t work. With the medium-shaft CTS pots I used, there was only just about enough room to fit a locking washer underneath and a washer and nut on the top. I tried with a flat washer underneath the locking one and there wasn’t enough thread poking out to get the nut on.

A 4-pole On/On mini-toggle, if you can get one with enough thread, would probably the simplest overall fixed series solution. Especially when it comes to stuffing the wiring through the f-hole.

Thank you so much for taking the time to put these schematics together.

I play mostly in the Bridge position. So practically, Option 3 was immediately appealing as I'll only need to pull two pots to get into series/out of phase.

Options 1 and 2 were appealing as they feed the bridge into the neck pickup when in Series mode. But, to get from the Bridge only position, I'll need to change the toggle plus pull two pots to get into series/out of phase.

Option 4 is the one I'm most curious to try due to the options on all settings, but I'm not sure how much of those options I would use, practically.

So...

Having said all that, and while I'm yet to set aside any of those options, after considering posts since, a one-switch single fixed series configuration with one pickup out of phase (polarity) may reflect the best outcome for me.

Noting the S1 switch won't fit, and that I would need to drill a hole to the front of the body, would either of these work/fit?

https://www.wiltronics.com.au/produc...toggle-switch/

https://www.altronics.com.au/p/s1385...toggle-switch/

I assume this could be done feeding the bridge into the neck when in series?

And so I can have my cake and eat it too, would it be simple enough to wire this with one push/pull pot that changes the phasing of a pickup? That way, I imagine I could retain the option of out of phase (polarity) in parallel via a push/pull pot, as well as have a one-switch single fixed series configuration with one pickup out of phase (polarity). I assume that if this push/pull pot was engaged with the 4PDT mini toggle you're suggesting, that it would then be in-series/in-phase.

It seems a great solution for in-phase/out-phase/series/parallel with minimal interference by too many pots in the circuit.

Thoughts?

Mathew.

A parallel/series in/out phase set of options would normally be perfect for the Free-Way Ultra switch. It’s a two row 3-way, giving you 6 positions, which would do everything you want all in a single switch… but currently costs more than the price of a small moon. And, while it is a very shallow switch, it has a huge diameter. So, probably fortunately, there’s no way to manoeuvre it in through the f-hole (see below) and would therefore require cutting an access hole in the back of the body. A ‘standard’ Free-Way *may* be able to squeeze through the f-hole, but (from memory) I don’t think it can provide all the options you want.

The good news is those mini-switches have just enough thread to mount through the top. They are listed as 8.9mm thread which matches mine, and look identical. When I test mounted mine on a spare ES I left the base nut on and that sat inside the pot hole that I used, and there was room for the flat washer and nut (but I didn’t use the grab washer). The top’s thickness on mine is ~4mm, but with finish could be a little more.

Attachment 44551Attachment 44552

Having a ‘phase’ push/pull in combination with the 4PDT mini-switch would work as you want. The mini toggle would give you series ‘out of phase’ and with the push/pull up you would have series ‘in phase’ ( or ‘out-of out-of phase’). And, the push/pull by itself allows parallel ‘out of phase’. The caveats being the 4PDT can only do its thing in combination with a Switchcraft style 3-way toggle switch where the two output lugs can be separated. And, this is still going to be a challenging layout to wire and solder… and a nightmare to fit through the f-hole and mount.

I’ll draw up a layout in the next few days.

Note that the second of those switches requires you to pull up on the switch first before it can be moved to the other position. It saves it being knocked by accident, but if you use it live, then it might not make for the smoothest of selections, especially if you have sweaty hands.

Also, you’ll probably want the switch to operate in either a vertical or horizontal mode. Which means that it needs to go within easy reach of the F-hole so you can hold it in the right position whilst you tighten the nut up. A stiff wiring harness may keep it in place, but it makes getting it through the F-hole harder and if you are like me, you won’t want it operating at a slight angle.

Simon, thanks for pointing that out about the actuator. I've ordered the first one, but just wrote to the supplier to confirm it does not have that same 'feature'. And yes, like you, it would forever drive me nuts if it were not aligned properly!

Scott, you're a legend. The freeway ultra switch looks amazing! But big...

I think the three way toggle I have is what's needed. The switches I have are:

1 x switchcraft three way toggle
switch
https://guitartrade.com.au/3-way-tog...ft-right-angle

1 x Bourns 500k Push Pull Pot
https://www.realparts.com.au/electro...l-pot-new.html

3 x 500k CTS Vintage Style Audio Taper Pot
https://www.realparts.com.au/electro...taper-pot.html

1 x Switchcraft Output Jack Socket, 3/8'' Long Thread, Mono
https://guitartrade.com.au/switchcra...ng-mono-nickel

Deep Thread Nuts (Switchcraft) - just in case

2 x Sprague .022mfd Orange Drop Capacitor

Vintage Braided Wire

Many thanks for your assistance and investing time with your suggestions and drawings. It's obvious you're passionate about this stuff. I'm really excited about where this discussion is landing. And I'm learning a lot along the way.

Mathew

Ok, one with everything...

Attachment 44556

The push/pull pot swaps the polarity (phase) of the Bridge pickup, and the output from that then feeds the 4PDT mini-toggle.

With the mini-toggle 'up' everything works as normal:
Bridge volume and Tone, Neck volume and tone all work as expected, and the 3-way Toggle gives you Bridge, Bridge + Neck parallel, Neck. Pulling the push/pull up changes that to 'Bridge (out of Phase) + Neck parallel' in the middle position.

Mini-Toggle 'down' switches to series mode, and changes several things:
1. The Bridge volume and tone are disconnected from the circuit.
2. The Bridge polarity (phase) gets reversed, putting it out of phase with the Neck. However, if the push/pull is 'up' then it gets reversed twice, putting it back in phase.
3. The Bridge pickup is linked in series with the Neck pickup.
4. The Neck volume and tone are connected directly to the output, ignoring the setting of the 3-way toggle switch, and act as master controls.

This configuration relies on the separate output lugs of the Switchcraft style toggle switch to enable the 4PDT switch to make all the changes. It wouldn't work with a standard kit box style 3-way.

This is going to be a challenging layout to wire up, particularly in a way that you can fit through the f-hole of an ES kit. You may need get some 4/5-conductor shielded cable to make the connections from the push/pull to the mini-toggle and from the 3-way right-angle toggle to the mini-toggle, as there are 3 or 4 connections between each.

The 'dark grey' wires on the diagram are the ground connections, and I tried to route them so that 'bundles' of wires will have a nearby ground point. But, how they actually get configured will depend on what type of wire you use and how you group everything to fit through the f-hole. The important part is that any 'dark grey dot' ground connection eventually connects to a ground point that leads to the jack(-). If you get what I mean.

Good luck!

Scott: Thank you so much for preparing this - it is perfect. I admit to being rather daunted by the amount of wiring, but after spending some time studying the diagram, you've made the routing clear very clear and clean. In fact, you could not have made this clearer and easier to follow. And it’s going to do precisely what I want I to achieve.

Scott/Simon: I have three FINAL questions:

1) Wire Choices. I’m proposing to use the following types of wire for this harness. Thoughts? Is there a better way?

Vintage Cloth Wire with Braided Shield (and heatshrink over the top)

• 1xground/1xactive between Neck Volume and Neck Tone
• 1xground/1xactive between Bridge Volume and Bridge Tone
• 1xground/1xactive between 3-way Toggle Switch and Jack
• 1xground/1xactive between 3-way Toggle Switch and Bridge Volume

Shielded 4 Conductor Pickup Wire

• 1xground/3xactive between 4PDT and Bridge Volume
• 3xactive between 4PDT and 3-way Toggle Switch

Vintage Cloth Wire OR Vintage Cloth Wire with Braided Shield (and heatshrink over the top)

• 1xactive between 4PDT and Neck Volume
• 1xground between 3-way Toggle Switch and Neck Volume

PVC Insulated Wire

• 1xground between Jack and Bridge (Ground)
• 6 small connections (active/ground) within the 4PDT and Bridge/Neck Volume

2) Shielding. Do pickup cavities require shielding?

3) Grounding. I’m installing a bigsby (style) tremolo with Tonepros Roller Bridge. I’m assuming I can still ground to the bridge, or will I need to drill a hole through to the end of the body and ground to the bigsby?

Thanks both for your ongoing assistance. Hopefully this will all be of use for others, too.

Mathew.

Easy stuff first.

2) Have you got covered or uncovered pickups?

If covered, then no, shielding is not required as they are enclosed in a grounded metal case and so are already shielded. You can shield the pickup cavities if you want to, it won’t do any harm, but you’ll need to run ground wires to each cavity, adding to the wiring count and you might want to think about widening the pickup cavity to control cavity holes slightly to make it easy to get the cables in and out.

If uncovered, then the single coil modes of each pickup could benefit from shielded cavities. Wiring notes above apply. But you’ve got a lot of wiring to fit in already and it’s very easy for wires to get tangled round pots when stuffing them in the F-hole and restricting movement and maybe requiring the harness to come out again to be sorted.

Before I put covers on them, The BK Mules in my Jimmy Page LP worked quite happily in single coil mode without shielded pickup cavities.

3) Grounding the bridge as standard is all that’s required.

1) Wiring.

The choices generally seem reasonable. There is no one right way to do it, so it comes down to a simple ‘does it work’ situation. Due to the complexity of the wiring, it might be easier to do more in singles than braided wire. Most of the runs are very short, and by the time you’ve cut the braid back to expose enough central core to wire up with you’ve got no braid shield left.

I’d always wire the short lengths in standard singles. e.g. between the volume and tone pots. Actually I’d rearrange Weirdy’s tone pot diagram so the orange drop runs between the volume and tone pot. The thick wire leads help keep the tone and volume pots aligned, making it easier to get the shafts through the holes.

As to other multicore wiring options, it all depends on where they are in relation to one another. Short distances, don’t bother. Also, if you use shielded cable but don’t connect the shield to ground - it’s not shielded. For shielding, you only need one end connected to ground unless it’s also being used as a ground link. Cut the unused end braid back and I’d cover it with heatshrink to be safe.

I tend to use tinned solid copper solid wire to do the links on switches. PVC insulation tends to melt back, so I use heatshrink on the bare wire for insulation. Though if using cloth singles, I may just run a longer length of the exposed core wire between adjacent contact tabs. I often use the solid wire to create a ground connection point. If you’ve got a lot of ground wires going to a pot, it’s easier to solder one solid core wire to the pot and then create a loop in the wire big enough to put your other ground wires through and solder them to that. You can normally get a larger diameter heat shrink over the joint if you think ahead.

I’d make your cardboard wiring template up and mark on the f-hole location before putting the components in place. Don’t forget that you’ll be fitting everything from underneath, so mark the template ‘top’ and ‘bottom’ and fit everything on the bottom side (I’ve got it wrong before myself).

Then you’ll have a much better idea of the length of runs and so to what wires to use.

You’ll also want to avoid cables showing through the F-hole.

You’ll find you’ll almost certainly want to extend the neck pickup lead, which you’ll need to do before you connect up the wiring. You’ll have the choice of running it to the neck volume pot first, and then taking the necessary wires off to the 4PDT switch, or to the 4PDT switch and then to the neck volume pot. Either way you’ll probably find the Neck pickup lead is a few cm too short. Tonerider use the same length lead for bridge and neck pickups. But as the neck lead has to run a longer distance and the lead comes out the ‘top’ side of the pickup when the screws face forwards so also has to run across the pickup cavity, it’s too short for a 335. Especially when avoiding running cables across the F-hole. You don’t want to spend ages getting a nice finish and then have a jumble of wiring spaghetti showing.

So I’d recommend taping wires together where possible to stop them flopping. This helps make the harness stiffer. Maybe harder to get in, but once in, easier to fit and remove.

You’ve got a lot of ground connections

Everything that Simon has said ++. Care and planning will often be the difference between getting the wiring working and installed and something getting smashed.

A lot of images incoming, so probably multiple posts…

First, I’d get some paper and make a rubbing of the holes, including the f-hole, and use that to cut your cardboard template. Then it’s time to work out where you want your mini-toggle and how you want the parts oriented to each other.

Attachment 44568Attachment 44569
Attachment 44570Attachment 44571

The right-angle 3-way is a big switch, but you most likely still want it oriented towards the pots. That means either pointed towards the f-hole or pointed up above the neck volume. If it’s the latter, then you need to check there will be enough clearance from the centre-block in the body to accommodate the switch and multiple wire attachments. Also, if you’re connecting your bridge ground wire from the bridge post then it’s going to be easier to go to the 3-way’s ground point, rather than the jack in my diagram.

Once you have decided on positions and orientations, you then need to think about the other components and wires routes.

Attachment 44572

As Simon stated, caps as the link between pots can be ideal and eliminate a wire link. But, they can also make things more difficult with how they need to be positioned, particularly when it comes to finagling the harness in through the f-hole.

The position of the components will affect how you need to route your wiring and which wire(s) would work best (and exposed in the f-hole or completely hidden). Sometimes you want a stiff harness, other times it needs to be more flexible. In the above configuration you may want a ‘U’ shaped wiring pattern that runs from the jack across the neck tone to neck volume to 3-way, then a loop back down that route then across to the bridge tone, bridge volume and mini-toggle. Using braid from the jack up to the 3-way, then a combo of braid and multi-core for the loop down and across to the bridge controls and mini-switch could be a viable option. The pickup leads length also comes into play, especially if you need to extend them, and where and how you want to attach them to the harness. And, will the harness be partially of fully inside the body at the time.

And…

… you also need to consider how you will need to manipulate the components to get them through the f-hole once everything is connected. The jack, push/pull and mini-toggle will all fit through the f-hole easily but once wires are attached it can become more tricky.

The right-angle 3-way needs to have one end in first then slide forward insert the other end. Which will be much more difficult with half-a dozen wires of various thickness attached. Possibly the most difficult will be the full-sized pots. They can’t go straight through and instead have to be inserted at an angle. This is where the position and way the caps are attached can make a difference, plus all the other wires and ground connections hanging off them. Challenging to say the least.

Attachment 44575Attachment 44573Attachment 44574

The more you can work out these issues, and even test them, before you fully commit to the full harness the more likely it will succeed.

First step, work out where you want everything and then we can all weigh in on the best way to achieve it.

You might find a short-frame toggle switch easier to fit than a right-angled one as it gives you a bit more room between components.

https://m.media-amazon.com/images/I/...AC_SL1000_.jpg

I don't know if there are any benefits of the longer frame switches over the shorter ones? I know Gibson normally use the longer frame models (and the right-angled switches by design need a long contact length), but was that originally from expedience as that was what was around, and now they just use them because of tradition?

I've redrawn Wierdbits' wiring diagram to work some ideas about how I will lay this out in practice.

Attachment 44585

In this first drawing (above), I've:
- moved the ground to the three way switch to be closer to the bridge
- run the neck pickup to the volume pot
- connected the third wire from the neck pickup to a spare lead in the 4-conductor wire to run it to the 4PDT switch
It takes the wiring around the f-hole, but there are still a lot of ground connections.

Attachment 44586

In the second drawing (above), I've:
- soldered the braided wire (running from the 3-way switch to the bridge volume) to the neck volume and both tone pots
- removed some of the ground connections which (I think) are no longer needed
This is about as minimalist as I can get the wiring.

Assuming the second drawing is a goer, I have some questions:
1) Should the braided wire running from the 3-way switch to the bridge volume and soldered to the pots be insulated with heatshrink?
2) I assume the wire running from the volume pot to the 4PDT should be shielded due to the length? If so, I assume I need to ground the shielding at one end (only)? And again if so, should it be insulated with heatshrink? Or do I not ground it, but instead run it against the braided wire running from the 3-way switch to the bridge volume and perhaps insulate both together with heatshrink?

I'm going to make up a mounting template tomorrow, and check how the components will fit through the f-holes to make sure everything is aligned correctly. Then, depending on feedback from the brains-trust, I'll start soldering it together over the weekend.

Mathew.

The second diagram is pretty what I was thinking.

If you connect the yellow output from the middle lug of the Neck volume direct to the 3-way lug along with the multi-core yellow, then you can eliminate the yellow vintage cloth run to the 4PDT. Electrically it is the same and eliminates the long wire run.

You only really need to heat shrink things that could move and short onto something else, depending on how much slack there is in the wiring. In your above diagram, the braided run from the jack to the 3-way would be the most important to cover. Any place where a braid etc could short your hot or potentially touch a ground connection in multiple places and create ‘ground loop’, then it’s better to insulate it.

In some cases, especially with small wires, heat shrinking connections can make them more robust as well as protecting them from shorts. If you do put heat shrink on connections, put it in place but (where possible) don’t shrink it down until you’re sure everything is solid and working correctly. And again, you always have to have an eye toward how it will fit through the f-hole.

The shorts runs between the Bridge vol push/pull and the 4PDT may be too difficult using the multi-core, so if it is proving too awkward don’t be afraid to go to single wires instead.

Hey Scott.

Eliminating the yellow vintage cloth to run the 4PDT sure does make things a lot simpler. Thanks for pointing that out - it's genius!

I'll take your advice on board regarding heat shrinks, avoiding ground loops, and wiring short runs when it comes to hooking things up. I'm feeling much more confident with this now - thank you.

I appreciate the photos you sent through - it's given me a lot to think about regarding fitting all this through the f-hole.

I'll post some photos when I start work on this over the weekend.

You've been really helpful with all this - thank you. Simon has been incredibly helpful too.

Photos to follow soon!

Mathew.