L 705 wiring question

Roger Palmer · From: Rossendale, UK

I was gonna put a coil tap switch on my L705 pickup, the one with the red, black, green, white and ground wires.
I can tie the white and green wires together on one side of the switch with the other going to ground to get a single coil but I would like to hear the other single coil to see which one I prefer. Anyone know which wires to send to the switch for this? If anyone has done this but couldnt hear any difference between the 2 coils that will do for me and I'll just use the green and white wires

Bruce Derr · From: Lee, New Hampshire, USA

Roger, I was also curious about the difference in sound between the two single coils of the 705.

I recently wired up a 705 in a GFI Ultra S-10. I connected a SPDT switch to cut either coil separately. It's a "center off" switch; in the center position both coils are connected in normal series humbucking configuration.

I found there is indeed a difference in the sound of the individual coils, but it is slight. You may not find it significant enough to bother with, but it's very easy to wire up if you're so inclined.

The SPST center-off switch has three terminals in a row. Connect the white and green wires together to the center terminal.

Connect the Red wire to one of the end terminals. Also connect the "tip" (hot) terminal of the jack to that terminal.

Connect the black wire to the other end terminal, and also connect the "ring" (ground) terminal of the jack to that terminal.

In one of the single-coil positions, the "hot" side of the coil is the outside of the winding. I was curious to see if this would make it too noisy, but that hasn't been the case.

I now have two guitars with 705s wired with coil cut and series/parallel switches. If I ever install another 4-wire 705 I will probably skip the coil cut switch entirely and put in only a series-parallel switch, because parallel sounds similar to single coil and, like series, has the advantage of being humbucking.

I drew up a diagram of my GFI wiring. If you're interested I will post it or send it to you.

Roger Palmer · From: Rossendale, UK

Thanks Bruce
That's exactly what I was after, I have your wiring for series parallel and will give this a go when I get some time
My coil cut switch just has 2 terminals so I'll probably leave it as is if there's not much difference between the different coils

Lane Gray · From: Topeka, KS

To test which coil you like better with a SPST switch, short green/white to tip instead of ground.
_________________
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Roger Palmer · From: Rossendale, UK

Ooh cheers Lane I'll try that

Roger Palmer · From: Rossendale, UK

Hi Bruce,
I would like your wiring diagram if you could take a photo of it and email it or something post might be a bit expensive as I'm in the UK
Also how did you attach the switches to the GFI? Did you drill holes or install a bracket underneath?

Bruce Derr · From: Lee, New Hampshire, USA

Roger, here's how I wired the GFI.

Bruce Derr · From: Lee, New Hampshire, USA

I had access to a bending brake so I made a little bracket for the switches. I drilled and tapped two 4-40 holes in the side rail of the GFI and mounted the bracket there.

Bruce Derr · From: Lee, New Hampshire, USA

This photo shows the hole for the original pickup's cable and the new hole I had to drill for the 705 reissue's cable.

Bruce Derr · From: Lee, New Hampshire, USA

This is how I wired my Carter back in 2014. This is the same as the GFI's wiring except it only allows one single-coil configuration.

This was formerly Bob Carlucci's guitar and he already had a switch installed (by the Carter factory I think) for his custom-wound tapped TrueTone pickup. There was just enough room for me to fit in another switch when I redid the wiring.

Bruce Derr · From: Lee, New Hampshire, USA

Here is a diagram for series/parallel only (most useful, IMO):

And single coil only (simplest to wire):

And single coil with either coil selectable. As Lane mentioned, this just allows you the alternative of shorting green & white to red, instead of to black. Note that this puts the outside layer of the coil on the "hot" side. I wondered if this would make it more susceptible to hum, but I haven't noticed any problems of that nature. However, as I mentioned, the difference in sound between the two individual coils is subtle at most:

Roger Palmer · From: Rossendale, UK

Great stuff thanks Bruce

I'll have a look at making a suitable bracket and play around with the coil tap to see if it's useful......probably just go with the parallel switch only though

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