RWRP tones in strats - basic question

[Marco Pancaldi]

I searched the forum about RWRP pros and cons and found inductance mesurations, experience of slight different tone, level loss etc...
A direct an immediate comparison, requiring re-magnetizing of the mid PU, is not simple to perform.

So, today I made a basic-stupid test: I used a spare japanese SC PU unconnected while the guitar (a Mex Tele Custom with bridge PU selected) was amplified. While strumming in different ways the open strings, I was moving with the left hand the spare SC near the strings (using both upper end lower "faces" of the pickup to test same/opposite polarity behaviour). The tele hasn't mid PU so my idea was to quick-test the influence on the bridge PU tone from a "phantom" mid PU.

I was surprised: the sound is not changing at all. The only way to sense a difference is putting the "disturbing" PU directly above the "sounding" PU: in this case you have huge interaction and distortion. In all the other cases I can't sense any evident difference in sustain or timbre.
OK: the test was not "scientific" at all: only one guitar, mid-low volume, only clean tone; the spare PU is probably not much magnetically strong.

Can you make a similar test and report? If my test is correct and confirmed, how can RWRP "in-between" combinations sound different from non RWRP? Or maybe the hum presence/absence can cause a different psycoaoustic reaction in some players...

Thanks
m.

[Steve Conner]

The effective self-capacitance of the pickup coil could be different depending on which end is grounded.

Also, the sound of an overdriven amp could change if the absolute phase of the pickup signal got reversed. The initial attack transient could change from positive to negative, say, and drive a stage into cutoff instead of saturation.

RWRP doesn't imply reversed absolute phase, but it's another factor that could happen by accident.

[Marco Pancaldi]

Steve:

The effective self-capacitance of the pickup coil could be different depending on which end is grounded.

This implies that every time a single PU or the whole guitar circuit is polarity-inverted some different Hi-end behaviour can be percieved, right?

Also, the sound of an overdriven amp could change if the absolute phase of the pickup signal got reversed. The initial attack transient could change from positive to negative, say, and drive a stage into cutoff instead of saturation.

I agree. This is a good reason to have always a polarity inverter at hand...

RWRP doesn't imply reversed absolute phase, but it's another factor that could happen by accident.

If I understand right, your expanation implies that a "perfect mirrored coil" (true reverse wound) with inverted magnet polarity can't change the "original" tone or polarity, while a simple RWRP with "inverted" PU wires can make some slight difference due to variyng capacitance. Please confirm or comment if you want.

[David Schwab]

The effective self-capacitance of the pickup coil could be different depending on which end is grounded.

Yes, but I think that mostly matters when the magnets are grounded, and they usually are not.

If you connect a single coil to a polarity inverting switch, and switch it and listen, you won't hear any difference worth worrying about. That's been my experience anyway.

What you will get is noise when you touch the pole pieces when the start of the coil is hot. This is why the mustang guitar had closed covers on the pickups.

[Mike Sulzer]

Also, the sound of an overdriven amp could change if the absolute phase of the pickup signal got reversed. The initial attack transient could change from positive to negative, say, and drive a stage into cutoff instead of saturation.

That is a very good, but subtle point. If we accept the propasition that human hearing is most sensitive to changes in the frequency content, then this implies that polarity is not mich of an issue when the signal processing is linear. But when it is nonlinear, as in a guitar amp, polarity can be an issue because the generated harmonics can have different levels. Just another interesting thing about electric guitars/amplifiers.