Pickup switching options - technical

[Jack FFR1846]

I've done enough research to understand some basic things. With a humbucker that's able to be split (what I have): the basic high output humbucker is to wire + into the top coil....- of the top coil into + of the bottom coil....- of the bottom coil to ground. This yields twice the output of one coil by itself.

Ok. So I'm looking at options and am a bit confused. I'll describe the switching options I'm considering.

Single coil: - of the top coil and + of the bottom coil get switched directly to ground. This yields only the output from the top coil.....1/2 the humbucker.

Parallel options: + of the top coil goes to + of the bottom coil. - of both coils go to ground. Still get humbucking effects because of the magnet reversals but the output is parallel, thus 1/2 the series humbucker.

I have no interest in phase reversals, so I'm not getting into it.

My issues: First....how do I avoid sudden volume drops switching between humbucking (series) and anything else?

I thought about a volume on each pickup, but they both really get put in parallel in this switching arrangement if the switch selects both. How is this done on a guitar with 2 volume knobs? (I have a Guild semihollow with this setup, but have no interest in ripping out the volume pots).

Everything I've seen simply has the pot going from the pickup to ground....varying how much resistance there is to ground. Is there another method.....using both sides of the pot? I don't want to loose the high output of the hum for harmonics.

jack

 

[beej]

You can also split the humbucker another way- use the bottom coil instead of the top. Or have a coil selector switch to pick which coil to use. For example, on the Axis SS the selector uses either the inside or outside coils depending on what's selected. You'll get a slightly different tone from each due to the position along the guitar's body.

In terms of the output issue, there's not much you can do. You're going to get less output and less inductance (more or less, the width of the frequency window) in split or parallel modes. There is always going to be a volume drop. That's just something you have to embrace. (Steve Morse, for example, uses the technique of adding a single coil in parallel to a humbucker to lower his volume and clean up his signal without having to change amp settings. Thus the crazy arrangement of pickups on his guitar.)

You could wire up separate volumes. Yes, they'll be in parallel. Would make a very small change in the tone, basically adding a third pot to the mix.

Another idea for splitting the pot- you could wire a pot to be a variable coil split. As you roll it off, it would slowly ground one coil. This way you'd have a little more control over the volume and amount of split.

 

[bkrumme]

I concur with beej on this one. There's not much you can do about the lower output. I deal with that usually by having a specific program on my G-System or Axe-FX for parallel pickup modes where the volume is a touch higher to make up for the lower pickup output. I just switch to one of those programs when I switch pickup modes on the guitar. Sometimes, though, I want the lower output so I get a more "vintage" sound that doesn't break up quite so quickly. The 2 center coils on my JP in parallel respond really well to changes on the volume pot, especially when I'm using a mild overdrive on a clean channel.

 

[edstorer]

Clean boost pedal

I play a couple of Silo's. I use a clean boost pedal to compensate for the volume difference between full humbucker and single coil, as well as the notch positions which are quieter than full humbucker.

Being the rhythm guitarist in the band, I have an occasional solo. Then I will switch to the bridge humbucker full and click the pedal on as well.

A guitar tech friend likes to use stacked 250 K pots in place of the tone control to modulate the coil split. Of course, finding stacked pots that aren't "Balance" pots is not an easy assignment. (Balance pots are set so both have zero Ohms at 12 o'clock. Turning the shaft clockwise increases the resistance of one pot while the other stays at zero. Turning the shaft the other way does the same thing for the other pot.