How do I Wire a Master Series/Parallel Switch?

rgand

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With just enough knowledge to get into trouble, I'm trying to learn something here. I asked a question on another thread that clarified coil tapping for me. OK, that doubled my knowledge. The question came up on series/parallel wiring. What I know about wiring is pretty much limited to that thread and the installation of a few humbuckers and getting them properly in phase. Oh, yeah, I also wired my Strat with the center pickup as a blend: http://www.seymourduncan.com/support/wiring-diagrams/schematics.php?schematic=3pickup_tele_blend That's fine but I'm probably going to stay with the two humbuckers and eliminate the middle pickup.

After a lot of searching on the internet and looking at various sites, including a search on this forum, I'm still unsure how to wire a master series/parallel switch into my guitar. My searches netted a lot of information on wiring each pickup with a series/parallel switch. What I want to do is leave them in series and in phase but combine them both with a master series/parallel switch.

Does any experienced person know of a diagram that shows 2humbuckers, 1volume, 1tone, 3-way switch (either toggle or lever) and a push/pull or mini toggle as a master series/parallel?

Thanks for help on this.
 
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Re: How do I Wire a Master Series/Parallel Switch?

When you say "master" series/parallel, do you mean you want one switch that will take both humbuckers from series to parallel mode?

P.S. Thats simple. Just requires one 4PDT switch.
 
Re: How do I Wire a Master Series/Parallel Switch?

Thanks for the reply, ArtieToo. When you say "take both humbuckers from series to parallel mode" are you talking about changing each pickup to parallel? If so, that's not what I'm looking to do. Instead, I would like to change the way the two pickups work together, leaving both individually in series. So from each pickup, there's one hot lead, one that goes to ground and the two coils are soldered together and taped off. Switching to parallel would change the pickups to work as one with a single hot lead and a single ground wire, bypassing the 3-way switch. It's probably a simple thing to do but I'm not experienced enough to figure it out.
 
Re: How do I Wire a Master Series/Parallel Switch?

You want both humbuckers to be in series? Like the old Gibson "recording" model did?
 
Re: How do I Wire a Master Series/Parallel Switch?

Yes, both humbuckers in series or parallel. I take it that was one of the capabilities of the recording model. This will cost less... :D
 
Re: How do I Wire a Master Series/Parallel Switch?

The only ready diagrams I know of that show pickups in series is either Jimmy Page wiring or Brian May wiring, but that is a challenge to read either of those if you are just learning.

For putting two pickups in series together on a DPDT switch, have the ground of one pickup connect to the hot/positive of the second pickup, and at the same time connect the hot/positive of the first pickup to ground.
 
Re: How do I Wire a Master Series/Parallel Switch?

You mean when the switch is in the middle position with both pickups on and you want to switch them into either series or parallel with each other?
 
Re: How do I Wire a Master Series/Parallel Switch?

That's correct, Demiac, except as GuitarDoc confirmed, the 3-way switch gets bypassed when in series. It looks like you don't even have to be in the middle position to go into series mode.

GuitarDoc, I thought that was the case with the 3-way switch. This is the elegant solution I was looking for. Pop the switch and they're in series, switch back and you're where you were. Thanks for confirming the diagram is what I want.
 
Re: How do I Wire a Master Series/Parallel Switch?

Now, I seem to recall that I read somewhere there is a volume change when in series. Is this correct? If so, is there a simple way to change the volume when it's in series, like a resistor or capacitor inline? I suppose a push/pull on the volume knob would be the ticket. Switch and twist, switch back and twist back. It wouldn't take long to get used to how much twist to give it.
 
Re: How do I Wire a Master Series/Parallel Switch?

You could make that switch a 3PDT, and add a couple resistors to the third section to form an L-pad. Like this:

L-Pad.png

When I originally drew that, it was for a single humbucker. You would simply connect it between the 3-way and the output jack.
I'm assuming a 500k vol pot. Those resistor values will change if you use a 250k pot.
Also, those values are the result of the exact calculation. You'd need to select the closest standard value.
You'd want the L-pad to be "on" when in the series mode.
 
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Re: How do I Wire a Master Series/Parallel Switch?

Thank you ArtieToo. I expect that will do what I need. It looks fairly simple. Yes, I am going to use a 500K pot so your chart is correct. I can use a separate switch and use my push/pull on the volume for a coil tap or something. I take it your chart shows the resistor values needed at various decibel levels on that pole of the 3PDT switch. Correct me if I'm wrong but I think I should choose the closest standard values for the db level I'll use the most. Or, is there a db rating on the pickups I should consider?
 
Re: How do I Wire a Master Series/Parallel Switch?

Correct me if I'm wrong but I think I should choose the closest standard values for the db level I'll use the most.

Correct. Typically, you choose either -3db or -6db. The volume increase, by going to the full humbucker. would be 6db, but -3db would probably be better. Typically, you still want to maintain a bit of boost when going to series mode.
 
Re: How do I Wire a Master Series/Parallel Switch?

That sounds good. I'll start at -3db and change it if it isn't right. It doesn't look like anyone makes a pot with a 3PDT push/pull so I'll round up a mini toggle or a slide switch. I have a great push on/push on switch like you see on the front of amps but it's only DPDT.

What would happen if I put the R2 resistor inline so it's used only when the two are in series? I could get by with a DPDT switch that way. On the diagram I found, it would be in the jumper between where the +lead of the bridge pickup comes in and goes to the -lead on the neck pickup. I did it in blue here:

Master Series-Parallel-R2.jpg

Maybe that would need to be the R1 + R2 value?
 
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Re: How do I Wire a Master Series/Parallel Switch?

I wired this without the added resistor(s) to see how it works and if the volume difference is too much.

I used a DPDT push switch. Tap, it's series. Tap again and it's back to parallel. With the guitar volume (linear pot) set at 10 in parallel, 8 brings the series volume back to be about the same. The tone is outstanding. I like the push switch and don't think the volume difference is enough to warrant replacing it with a 3PDT mini toggle to do the job. The pickup selector is bypassed with this and that's good. I'm pleased.

Here's the wiring again:
Master Series-Parallel.gif
 
Re: How do I Wire a Master Series/Parallel Switch?

^^
+1 on this. When I rebuild my Ibby, I'm putting a push/pull on the volume that does this, combined with the pickups mounted in Triple Shot rings. I might even put in a master phase push/pull on the tone knob. Why not go for all the possibilities?
 
Re: How do I Wire a Master Series/Parallel Switch?

^^
+1 on this. When I rebuild my Ibby, I'm putting a push/pull on the volume that does this, combined with the pickups mounted in Triple Shot rings. I might even put in a master phase push/pull on the tone knob. Why not go for all the possibilities?
I like having choices, too. I'm considering a push/pull blowout switch on the tone knob. The only thing that keeps me from it is the difficulty of finding a good 500K linear pot (my preference only) with the push/pull on it. I have a linear mini pot with one but it's an alpha and I'm a little unsure of the quality. I'm really curious how the blowout and series switch would sound together.
 
Re: How do I Wire a Master Series/Parallel Switch?

Nice. Btw, I probably should have mentioned that I've never actually done the L-pad. But it looks like you got it worked out. :)
 
Re: How do I Wire a Master Series/Parallel Switch?

Nice. Btw, I probably should have mentioned that I've never actually done the L-pad. But it looks like you got it worked out. :)
In a perfect world, the L-pad would be the best but it's easy to just dial the volume down 20% with a quick twist if needed. When I push the switch, my hand is right on the volume anyway. It would be useful, though, if someone made a 3PDT push/pull pot for this kind of wiring.
 
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