Middle Pickup as Choke for Vari-Tone Inspired Tone Control

[Deleted]

Hello, All.

I've been lurking awhile and it's sparked a question.

I've been familiar with middle pickup blends for some time (Brent Mason, Bill Lawrence Hendrix Wiring, etc), and noticing the tonal results of adding a second parallel pickup somewhat resemble those of the Vari-Tone or Lawrence's "Q Tone."
I've been wondering if adding a capacitor (or switchable capacitors a la the Vari-Tone) in series with the second pickup would have similar coloration possibilities.

Not a seasoned theorist by any means, so very good possibility I'm missing something otherwise obvious, but I thought I'd ask if anyone had done any such mad science.

[frets]

It should. Depends on what tones you are looking for and can create using differing capacitor uF values (microfarads). The series configuration will give you a “boomier” tone. Although not Gibson Varitone values, I find .01, .015, .022, .033 and .047 to be the most serviceable (on a 6 position rotary with a bypass setting). Using that setup, you should be able to craft your tone on either pickup.

[Deleted]

Thanks, frets!

I will give those values a go. When you say boomier in series, we're not talking about the pickups being in series, are we?

[JohnH]

I think it's a great idea! The inductance of most pickups is right in the range that can have a nice effect in a mid-shaper or Varitone circuit. And being a pickup rather than just a passive coil, they can contribute to the input signal as well. That could help mitigate the tendency for such circuits to reduce the volume.

[Deleted]

Thanks for the encouragement, JohnH.

I hadn't thought of the volume issue. I was mainly thinking of maximum color for minimum parts under the hood. The potential to solve an associated problem at the same time is even better.

[frets]

I was talking about pickups or coils being in “series.” I thought you mentioned the pickup being in series. When a pickup(s) is in series, the volume is louder and the tone tends to be “deeper” more pronounced. At least that’s what I hear.

[Deleted]

Got it. Agreed on the sensation of series single coils.

My thoughts are two parallel coils, such that, when looking backwards from output to ground on the middle pickup, it looks like the series capacitor and inductor of the Vari-Tone circuit, essentially just replacing the transformer/choke with the middle pickup itself. I am so Shakey with the terminology, I might be butchering my thoughts, but here is the gist.

Like so (Omitting pickup selector and tone pot, etc.):

GND----------Middle Pickup--Switching Caps-->Hot Output
/
GND----------Bridge Pickup------------------>Hot Output

I actually used one of your drawings from the super long Gibson Vari-Tone thread to mock it up, frets. If you'd give me permission to post it and I could figure out how, it'd probably be easier to critique.

[frets]

Sure😺

[Deleted]

My apologies, frets.  I've managed to turn your drawing into a poorly illustrated cartoon.  Hopefully it makes sense.

[Deleted]

It appears I've reinvented the HOoP mod. It does provide some pretty outrageous cluck near the lower values, but just sounds like a funny phase issue at higher values. The only instance where it has any resemblance to a Vari-Tone is if I move the middle pickup as far away as possible, which might be an option. I think all of this makes sense in terms of the pickup generating frequencies back into the output through the same capacitor that would carry away in a Vari-Tone, just partially out of phase due to the capacitor. Any thoughts?

[Deleted]

...perhaps a diode to prevent generated current from the pickup flowing to the output?

[gckelloch]

I have a similar setup on a few guitars but with just one much lower Cap value. I use 2nF to get a ~3kHz crossover between pickups with the blend fully engaged, which dips the signal there when the pickups are OoP. You could at least try flipping the phase of the Middle PUP. To me, it sounds very similar to the bridge PUP with a bit softer upper midrange and a slight quackiness. Assuming typical Strat PUP inductances of 2.3H~2.8H, I'd try cap values of roughly 2nF, 3.5nF, 7nF, 15nF & 22nF.

[Deleted]

Thanks, gc.

I'll try the middle OoP.

[gckelloch]

47nF OoP could be useful as well for an anti-boxy sound. I find my OoP blend sounds are brighter and closer to one SC PUP sound than the IP blend sounds. Keep in mind that if the pole pieces are grounded, you'll need to somehow separate and run that connection directly ground so they don't act as antennae for noise when wired OoP. My guess is the pole pieces in most SC PUP are not grounded, but I dunno.

[Deleted]

Flipping it OoP does make it more more useable, though seems strange. Reading Bill Lawrence's commentary on capacitors shifting phase by 90°, I would expect 270° OoP to sound much like 90° out of phase, being that they are both OoP by the same distance from 0. If it sounds good, I'll take it. In the same vein, decking the pickup makes the whole thing sound more like a legit Vari-Tone, so that's also a possibility, and I'm really pretty solidly in the "neck pickup most of the time" camp. I really appreciate your helping on this, gc.

[Yogi B]

Apr 29, 2024 10:57:50 GMT -5 re said:

Reading Bill Lawrence's commentary on capacitors shifting phase by 90°

Where? Googling "Bill Lawrence" "90 degrees" leads me to a PremierGuitar article (and a suspiciously similar article from InfintyGuitarWorks), so any commentary therein is that of the respective author(s). In the case of the former, that is a certain Mr. Dirk Wacker and should accordingly be taken with a pinch box of salt.

Only near the frequencies where the capacitor becomes the dominant impedance in the circuit does the introduced phase shift tend towards 90°. This occurs at low frequencies, where the cap (in combination from the loading of the bridge pickup) is also filtering out most of the output from the middle pickup. Thus, the region where the 90° difference occurs is where you're getting mostly the output of just one pickup anyway.

---

(After reading a few more articles published on InfintyGuitarWorks, there's definitely some thinly disguised plagiarism going on.)

[Deleted]

Yogi, your post reads as if you're offended.

To answer your question "Where?," Well, a long, long time ago, before the Google monopolized the information game, we had guitar magazines like Guitar Player and Guitar World, and for a very short time Steel Guitar magazine. Bill Lawrence was enough of a gadfly in the industry that they liked to interview him to keep us lowly, uneducated guitar players befuddled and in our own lane. His exact wording and the context escapes me but I remember him answering a question about capacitors with terms like "phase angle" and "90° phase shift."

I may have created a mental portmanteau of that and the half out of phase trick (The man himself, in his handwritten schematic labeled it "half out of phase," probably just to keep us luddites guessing.)

In case you missed it, that was meant to be as caustic and dismissive as your post. I suppose us verbally kicking each other in the ankles isn't very educational in either direction, now is it?

[reTrEaD]

Apr 30, 2024 2:05:50 GMT -5 Deleted said:

Yogi, your post reads as if you're offended.

I reckon that depends on who's doing the reading and how they define offended.

I view "offended" as being an adverse reaction to something interpreted as being personal affront. I'm not detecting that in Yogi B's post. However I do detect something less than reverence in regards to his opinion of Dirk Wacker's writings. I admit to being somewhat biased in that regard. Dirk Wacker has a history of connecting dots in ways they were never meant to be connected. And I freely admit to intentionally misspelling his name, on occasion. 😮

I see you've deleted your account. That's unfortunate. This might have turned into a useful conversation into the misnomer "half-out-of-phase". But without an account, you won't be able to participate. But, as they say, it is what it is.

So, sir, I bid you adieu and wish you the best in your search for knowledge, where ever that may lead you.

[newey]

Seems like the former member was a bit thin-skinned. He made a statement as to what he believed Bill Lawrence had said. YogiB asked where he had seen that, pointing out that all he had found were some other writings whose expertise he questioned. The deleted member said it was just a recollection of something, and he had no citation to it. I would have thought that should be the end of it.

Where in all of that there was any reason to go off in a huff is a puzzle to me.

[gckelloch]

Maybe he thought "Dirk Wacker" was meant as a smear of him or Bill Lawrence? Otherwise, I don't see how he would be offended. Shame, because I was gonna get us tickets to see Jimmy Carr. Serously, man. Come back if you read this. I'm sure it was all just a misunderstanding.

[JohnH]

Hey come back!

It's been a good conversation and some interesting things that you are trying. Please don't worry about our opinions on DW. We come across his his stuff often.