Help - Dummy coil on SSS with RWRP mid PU using Super Switch

[RedStrat]

Hello there,

I'm quite new to this forum but have been reading a couple of posts here about dummy coils.

Some background:

I play in a church band and my main instrument is a Fender Stratocaster SSS with rwrp middle pickup.
In church we have a auditory loop. This loop is really hindering my playing (it feedbacks through my single coils), I've tried a lot of different things but humbuckers seem to be the best remedy.

When I found out about a dummy coil, that seemed like the right solution for me. I can keep my single coil sound and won't have to modify my guitar too much. Also it's a fun thought experiment and gives me some tinkering experience.

I've been reading the forums here (I've seen the Dummy Coil Experiment - Successful! thread but it doesn't quite give me the solution I'm looking for) and figured out a lot already.

I now have a wiring diagram made using DIYLC so I can also use the analysis function to verify if my diagram works.

I am now at a point where I have achieved the following using a Super Switch:

Position 1: Neck + Dummy -> Hum canceling

Position 2: Neck + Middle -> Hum canceling

Position 3: Middle -> No Hum canceling

Position 4: Middle + Bridge -> Hum canceling

Position 5: Bridge + Dummy -> Hum canceling

In the ideal situation I want the middle pickup to also be hum cancelling as to not trigger the auditory loop's feedback while playing. I already know that I somehow need to swap the wires from the dummy coil for the middle pickup to be hum cancelling as well. However I would prefer it if I can do this without needing to use an additional switch next to the super switch (dpdt for example).

If anyone has any bright ideas on how to rewire this so that I can use all positions as they were and they are all hum cancelling, I'd love to hear your suggestions!

[newey]

RedStrat-

Hello and Welcome to G-Nutz2!

I'm pretty sure that what you want is possible with a superswitch, but your diagram has several issues (and this was a first look, there may be others.). Particularly, the issues I see are with the lower right hand pole of the Superswitch.

The middle pickup white wire (kinda hard to see the white wires on a white background, I usually use grey for white to make it more legible) connects to the lower left pole of the Superswitch, to lugs 2-3-4. The common lug from that pole is then connected to the lower right pole of the switch, via a white jumper. The lower right pole is then connected to the V pot, and then to output- but only at positions 2 and 4 of the switch. At position 3, the lower left pole is connected only to Tone pot 1, where the connection ends- no output.

I'd use the lower right pole common lug to connect to the volume pot, and disconnect the connections at 2 and 4. Next, connect the dummy coil to lug 3 on the upper right, via a jumper. The middle pickup hot then needs to connect up to the open lug 3 on the upper left, so it gets the dummy at 3. That should do it, but you should redraw it accordingly so we can double check it.

[RedStrat]

Thanks so much for welcoming me here and looking at the diagram!

I changed the white wires to grey (thought that was a great tip indeed) and also changed the wiring according to your directions. However the analysis of the tool now tells me that neither position 2 or 4 are connected and 1,3,5 aren't hum cancelling anymore. It looks like it's not picking up the dummy in this way.

Any idea how to go from here?

[newey]

Sorry, my fault. I thought of all the steps, but omitted writing 2 of them down!

You need to also connect the bridge and neck "hot" wires to lugs 2 and 4 on the lower right pole, so they connect to the output in 2 and 4. The middle pickup wiring to the lower left pole needs to change as well.Leet me try to pull a drawing together for you. A picture is better than my verbal description, I should have just drawn it up to start with, there's too many changes to follow written steps.

As for why it's not showing hum-cancelling (and assuming it was showing hum-cancellation on your original), I'm scratching my head a bit. We didn't change any of the dummy coil wiring other than adding a jumper to lug 3 on th eupper right. But let me look at this a little further.

EDIT:On further reflection, the dummy coil is supposed to be in series with the coil it is quieting. Your diagram had them in series, but the jumper between the upper right common and the lower left common needs to be removed- as that ends up putting the coils in parallel with the dummy. Lose that jumper and see if that helps the hum issue. Meanwhile, tring to get a quick diagram done here, it won't be pretty but hopefully accurate!

[newey]

Here's my take, but my confidence level is not 100% and my track record around here is even worse, so let's get some other inputs before you go a'solderin'. I should also note that my question mark here is as to the tone pot wiring, I tried to reproduce the classic Strat tone pot wiring where both pots are in circuit at position 4. But for my money, the better way is to simply move the middle tone to the bridge as I want a bridge tone more than I want/need a middle tone. And only one tone control in the circuit at a time with that mod, if the guitar is using a std. shorting-type 5-way instead of the Superswitch. With the SS, though, we have to wire each tone control where we want it, as the switch doesn't internally short the tone pots into the circuit at 2 and 4, doing the work for us.

[RedStrat]

I think I understand what you're trying to say. In my initial draw up the tone pots would only work on the 3rd and 5th position and not on the 2 and 4.

Also I wasn't planning on soldering or even ordering the switch until I'm sure this idea is going to work haha.

I now wired it up as you drew (See added picture) but there still are some issues. It's still not properly picking up the dummy coil in the 3rd position and is now picking up the middle pickup in position 5 as well. I'll add the analysis as an image too. I'll see if I can figure some of this stuff out myself as well.

[RedStrat]

I have been tinkering some more and redid the layout quite a few times until I finally got down to this.

I am unfortunately not able to use both the tone knobs in the 4th position, but that's a sacrifice I'm willing to make.

Only thing I still haven't figured out is how to reverse the wires of the dummy coil only for the 3rd position. That's why in this diagram the 3rd position isn't properly wired yet.

I did figure out that I can do it with a second dummy coil but I'm not certain if I actually have space for 2 dummy's in my guitar. So if I could figure out a way to switch the wires around but only in 3rd position, then we've cracked the code!

[RedStrat]

Yesterday evening I believe to have found the solution!

I figured that essentially I need a second coil to be able to make the RWRP middle coil hum-cancelling as well. So I wired up a humbucker in the diagram (called it the Dummy bucker) and that seems to have worked. Now I don't think I have to space to place an actual humbucker, but a humbucker in single coil format should fit somewhere beneath the pickguard. I ended up buying a cheap hot rail humbucker from Amazon (with a resistance of roughly 12-13K, so 6-7K per coil).

I am now waiting for the super switch and the hot rail humbucker to arrive and will then start the soldering.

Here is my current diagram and the analysis.