Variable Series/Parallel with a Pot?

Re: Variable Series/Parallel with a Pot?

I'll refer to the pots in your diagram as:

.......1.......
................
................
...2 ......3...

Pot 1 would just be putting a resistor of the value of the pot between the series link. This does not break the series link.

Pot 2 would ground the white wire, which would start to work towards putting the pickup in parallel, except the wire is either grounded or not. Otherwise you're just putting the first end of a resistor on the series link, with the second end of the resistor on nothing - i.e. the resistor is out of the circuit/does nothing. Again, the wire is either grounded or it's not.

Pot 3 has the exact same funtion as pot 2, just replace the word "ground" with the word "input".

This diagram will only switch the pickup between series and parallel, with no real in-between sounds. Because again, the two coils are either in series, or they are in parallel. Period.

Here's an analogy for what I mean: Saying you want an in-between sound of series and parallel is like saying you want your car to drive between the first and second gear. You're either in neutral, first gear, or second gear. There's no way around that. You can switch gears, but you can't be in both gears. It's not physically possible. You can only rev the engine to the gear's max RPM (volume knob at 10), or you decrease the RPM until you're just idling (volume knob at 0).

All anyone and myself can do for you at this point is tell you that what you want is not possible.

If the resistance/value of Pot 1 is high enough, it could effectively break the link between the two wires.

As for pots 2 and 3: is it true that the wire is either grounded or not? A regular volume pot works by placing a variable resistor (pot) between the pickup signal and ground. And there's the spin-a-split scheme where you gradually shunt a coil to ground by decreasing the resistance between the series link of a humbucker and ground.

I'm not sure this idea works though. At the 50% of this triple ganged pot, you have the series link still somewhat connected (how much depends on the resistance of the pot at this point), so you're kinda grounding one coil and kinda shorting the other one.

It'd be interesting to see if it worked at all.
 
Re: Variable Series/Parallel with a Pot?

If the resistance/value of Pot 1 is high enough, it could effectively break the link between the two wires.

Then what value is it? The resistor reduces the current, not remove it. (Hint 1: Find the current or voltage of the series link itself. You will need a resistor large enough to ensure that much current or voltage is unable to pass through. Remember the Zero Property.)

As for pots 2 and 3: is it true that the wire is either grounded or not? A regular volume pot works by placing a variable resistor (pot) between the pickup signal and ground. And there's the spin-a-split scheme where you gradually shunt a coil to ground by decreasing the resistance between the series link of a humbucker and ground.

Pot 2 for example would introduce a resistor in between the coil's finish wires and ground. Put a variable resistor between your finish wire and ground and see what happens (Hint 2: I tried it, and I know what happens. Go back and look at Hint 1). It will not work like a spin a split or volume pot. It is either grounded, or it isn't. Remember the definition of a complete circuit includes a (-), or a ground? There needs to be a ground, or it won't be complete.

I'm not sure this idea works though. At the 50% of this triple ganged pot, you have the series link still somewhat connected (how much depends on the resistance of the pot at this point), so you're kinda grounding one coil and kinda shorting the other one.

It'd be interesting to see if it worked at all.

This is another problem of the design.

So far it is Artie, GuitarDoc, and myself saying this will not work. I strongly doubt it will work.
 
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Re: Variable Series/Parallel with a Pot?

I don't want parallel blend or series/parallel switching with a pushpull or a switch. I want continuous adjustment between parallel and series so I can get in between tones and be able to adjust continuously between them instead of only having discrete, static options of parallel or series.

This is simply not possible. You cant get in between tones from parallel and series. It is either parallel or in series. like Myaccount 876 said about car gears. To further put it you can put your car either be in forward gear or reverse not in between. When in series the current flows from one coil into the other with one end grounded and the other output. For Duncans Green is connected to ground red and white connected together and Black output so current flows from coil 1 through the red wire into the white and exits from the Black.
When in parallel Current flows simultaneously from both coils with each coils end or start connected to ground and then start or end of the respective coils to output. In Duncans we connect the green and the white to ground. and Red and black to output.

In between tones is just not possible, as when in parallel mode one end of he second coil NEEDS to be grounded .

I will wait until Arties next post. I respect Artie a lot he is brilliant with circuits. And if he says this cannot be done believe me it cannot. And even he does give a circuit this is not going to be simple.

What you can do with a pot is Spin a split. A split tone would be similar to a parallel tone and yes that you can BLEND in.
 
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Re: Variable Series/Parallel with a Pot?

You could have saved yourself a lot of time and trouble if you would have stopped after reading post #2.
 
Re: Variable Series/Parallel with a Pot?

It's either grounded or it isn't.
This is in conflict with the idea of a volume pot which is why I'm continuing to wait for a proper explanation.

Why is it not possible to have the coils in parallel but also feed the second coil with a portion of the output of the first?
 
Re: Variable Series/Parallel with a Pot?

This is in conflict with the idea of a volume pot which is why I'm continuing to wait for a proper explanation.

Why is it not possible to have the coils in parallel but also feed the second coil with a portion of the output of the first?

...Because to be in parallel, the finish of the first coil must be grounded. A resistor in between the finish wire and ground does NOTHING. The finish wire is either grounded or it is not - if it is not grounded and not connected through the series link (which you can't break with a resistor), then the first coil is completely taken out of circuit due to no longer being completed. This is NOT the same of as a volume pot, which will eventually ground both the start and finish of the circuit; sending the whole circuit to ground. The volume pot and your scenario are completely different, and in the context of your scenario, not the volume pot, certain wires are grounded or not. With the series link, ground the north finish wire, and you've just grounded the south start wire - you've just split the pickup.

How many times do we have to say this will not work? You simply cannot have a pickup in both series and parallel - it is either series, parallel, or split.
 
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Re: Variable Series/Parallel with a Pot?

Why is it not possible to have the coils in parallel but also feed the second coil with a portion of the output of the first?

If they're in parallel, then they have common start/end points. Feeding "a portion of the output of the first" to the second coil would mean feeding the first coil as well. It also means you're feeding the second coil to itself (and the first coil) as well. Ignoring the problems with grounding, you're trying to get an electric snake to eat its own tail, but hoping that will make it grow longer.

If you want to get a third coil involved, you could have them in a "Y" configuration and get a blend of series and parallel tones that way. You can't do it with only two coils.
 
Re: Variable Series/Parallel with a Pot?

I generally don't like to post "theoretical" ideas until I've actually tried them out, but I came up with a way of pulling this off. It's a bit of a "cheat", but it works on paper. (Famous last words.) It will also make the axe somewhat of a one-trick pony. But potentially, a very cool trick. Think of this as a quasi-one-humbucker guitar, at the cost of two. Let me explain. ;)

Take a 2-HB'er axe, and install a Custom 5 at the bridge and a '59 at the neck. Wire the stud coil of the 59 and the screw coil of the C5 in series. Wire the screw coil of the '59 and the stud coil of the C5 in parallel. Now connect those two hot wires to a blend pot. You can now progressively and smoothly blend a C5/59 hybrid pup from series to parallel. (I told you it was a cheat.) :)

The cool thing about this "hybrid", is that the C5 coil is always at its natural bridge position, and the 59 is always at its natural neck position. A true C5/59 hybrid.

Like I said, sounds good on paper. Now just to wire her up. Film@11. (Not saying which week.)

Artie
 
Re: Variable Series/Parallel with a Pot?

This doesn't answer the OP but it has elements of it.

asset.php

It's using a tapped pot. From memory the pot is 50K and the tap is at about 20K.
At the tap you have mainly single coil and at full excursion series but not totally. It works like a blend/split.
 

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Re: Variable Series/Parallel with a Pot?

um...I'm in no way expert in circuits but why does everyone think in analogue only? I mean, you said yourself that you understand digital better, I assume you understand basic PCB's too. Sketch up a circuitry that accepts two inputs, the two coils of your humbucker. Then split both signals and combine one track in series, the other in parallel. One pot or encoder could give you whichever in-between sound you wish for. In either case, pot or encoder, you could have it switching on/bypass (true bypass) where you combine the coils to the normal operation you would have them. You would have to deal with buffered signal of course but if it's that important to you, I don't see why not.. Just my humble opinion!
 
Re: Variable Series/Parallel with a Pot?

Again, not going to get deep into explanation, but the resistance of the pot in the circuit is going to kill the output.

If you want something that can go from humbucker sounds to single coil kinda sounds without the hum, try one of these - http://wildepickups.com/Q-filter.html
 
Re: Variable Series/Parallel with a Pot?

That's probably a spin-a-split.

http://www.mykaguitars.com/instruments/015/process.htm
"Master volume, master tone, series/parallel pan for each pickup"
84.jpg


I believe this is more similar to the washburn VCC wiring actually.

VCC_wiring.jpg


I do not know the washburn color codes for their pickups, but the general consensus on the VCC wiring is that it does kinda do the series to parallel thing.
Maybe someone smarter about wiring can tell us what its doing exactly.
 
I think it is possible.

Using pot values your original guitar uses, you need to buy a ganged pot.

Ok, Ground your bridge pot.
Solder the hot wire of the bridge pickup to the middle terminator of the back pot.
Then solder the ground wire of the neck pickup to the top terminator of the back pot.
This pot now can join or separate the series circuit you just made.
Now solder the top terminal of the back pot to the center terminal of the front pot.
Solder the bottom terminal of the front pot to the ground of the bridge pickup.
Solder the top terminal of the front pot to the hot wire of the neck pickup.

I suspect that now, you have constructed a series/parallel blend circuit for your guitar or bass..

Try this and let me know how it goes.

Thanks for the idea. I am going the try it for the bridge/mid switch position on a strat now. Knobs will be volume/tone/blend. Have fun with it.
 
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It can't be done. 7 years ago I used up a ream of paper doodling up every possibility. As an experiment, do this: draw two AA batteries on a piece of paper. Now connect the ends such that they are in series and parallel at the same time. What voltage would that be?

However, I did come up with a cheat, that creates the equivalent sound. Install the classic C5b/59n combo. Completely normal. I use a switch to make the wiring C5 stud with 59 screw in series. Then the C5 screw with the 59 stud in parallel. You have two virtual C5/59 hybrids. Outputs go to a blend pot that fade from one to the other.

It's a cheat, but it works electrically on paper. One of these days, if I don't die first, I'll actually wire it up.
 
I've seen something similar before, when we were investigating this. If you redraw this with the pot turned all the way to the left, the left coil is connected through the top pot to ground. (Via the bottom pot.) With the pot turned all the way to the right, then the right coil is shorted out, through the bottom pot. You'd have split rather than series. And in the in-between position, there's so much resistance in the lines, you'd kill the character of both pups.

It's an interesting idea, but sonically, it just won't work.

Edit: I didn't mean my 1st sentence in post #39 to be quite so absolute. I'd love to see someone come up with this. But I just don't think it can be done.
 
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