Bill Lawrence 5 way wiring question

[shadowfire90]

This is an easy one.

Going through Premier guitar and other wirings to try for a different type of setup I remembered this existed. What I found odd was how the tone control is wired. Would this do anything differently than your standard tone control. I find it odd how the capacitor is soldered in. Almost like a bass cut mod. Would this do anything differently?

Here's Bil's original drawing


and something quick I put together as I didn't care for premier guitars diagram so I made my own using older Seymour Duncan diagram images I put together.

[freefrog]

Re: Bill Lawrence 5 way wiring question

It's apparently wired like a bass cut [EDIT: and in the 5th position, it gives "10% less low end"] but when the PU's are in series and OOP, it reacts differently : the "hot" of one pickup goes to ground through the cap then through the other pickup. So, this cap does +/- the same thing than a tone control lowered @ zero for one of the two pickups. Hence the mention: "1/2 out of phase". They are out of phase along the bandwidth allowing the two pickups to be heard together. Beyond the cut off frequency due to the cap, the filtered pickup can't be heard no more and the other one delivers the goods alone.

Below is the related frequency response (not far to evoke the 2d or 4th position on a Strat). It's a theoretical measurement. If time permits, I'll add a real lab measurement that I've somewhere in my experimental data.



I prefer full OOP, personally - And a Q filter can be tuned for the kind of response due to the wiring above, without the related downside ("hummmm" once the RWRP PU out of phase with the other one).

FWIW (lmy 2 cents, as usual).

[freefrog]

Re: Bill Lawrence 5 way wiring question

NOTE before to start a busy day...

Below is the frequency response of PLAYED pickups: Tele 1/2 OOP vs Strat PU's in parallel.



Below are the crude resonant peaks of some Tele PU's with 4 positions due to the BL wiring: bridge PU alone in pink, neck PU alone in green, both PUs in series 1/2 OOP in white... I've not sampled bridge and neck PUs in parallel and in phase in this measurement. [EDIT: and I think that I've used another value than 10nF for the cap in this case, so the mid dip for the half OOP curve looks a bit different.]



The blue line concretizes a tone that I had initially forgotten to mention: one of the 5 positions in the Bill Lawrence wiring actually wires the cap like a bass cut filter so you were right, shadowfire90.

The sharp peak at low frequency in the blue and white lines concretizes the increased hum potentially due to this wiring (albeit it sounds good: Bill did know what he did; it's just that any reality has its own downsides, as we all know as human beings).

Again, FWIW. Back to work now.

[shadowfire90]

Re: Bill Lawrence 5 way wiring question

Thanks for all your details and insight. I love the frequency response photos as well. Next time I got a question I'll message you directly.

I did find it odd about the capacitor. As much as I love bass cuts my first draft I'll probably do a secondary tone control. Though this does give me an idea.

Yeah it's been a while since I looked at half out of phase. Jerry Donahue I remember boasted about this wiring when he spoke about his guitar Fretking made him a while back. The only alternative to standard out of phase I had some success with was "series out of phase" using a dimarzio super distortion in the bridge. With something more medium output it was like a tin can but the super distortion worked out really well.

[freefrog]

Re: Bill Lawrence 5 way wiring question

You're welcome. :-)

It's not a problem for me to share publically some my archived data, as long as it seems to be useful for someone.


Regarding OOP and to sum up my humble experience: it's totally useable as long as the pickups used are slightly mismatched or can be set each at a different output level.
Conversely, two stricly identical pickups set at the same volume will probably sound too thin once OOP, weither it is in parallel or in series.
I think that's why 1/2 OOP has initially been designed: it avoided the sound to become too thin...

Sidenote: strangely, a properly designed Varitone can mimic the OOP sound in a Gibson style guitar. :-)

FWIW: 2 other cents.