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OK. While I was waiting a call from the hospital, I've tried to think about something else. So I’ve done a few sims that I share below. Each pic shows ten lines, translating the resonant peak of a humbucker whose coil splitting is progressively altered by a variable resistor (goiing from 500k to 0 Ohm).
Pic 1 illustrates what happens when a HB in series has the variable resistor between coils, going to ground (as shown by “Fig 1”, in post 1). As I’ve tried (and failed) to make it clear in my post 11, the resistor “mellows” the signal and “flattens” the resonant peak a bit like a tone control would do as long as its resistance is high. It’s only when this resistance is low that one coil starts to “loop” itself to ground, leaving the second coil working alone. That's where the resonant peak becomes higher pitched and the level much lower...
The second pic shows what happens when a HB wired in parallel has a variable resistor between ONE of its coils and ground (as shown by “Fig 2” in post 1). This time, the control affects essentially the frequency of the resonance, which is logical since it passes the HB from ¼ of its series inductance (in parallel) to half of this inductance (when split): it affects frequencies more than output level.
The third pic shows what happens with a cap in series with the variable resistor, as Gstring has wired it (if I’ve understood correctly what he said)…
...And that’s where my previous explanation was not complete at all. :-/
The 5nF cap has in fact TWO actions in this case:
-it acts like a tone capacitor to ground for coil 1;
-it's also a series capacitor between ground and coil 2 and works as a high pass filter for it.
These two functions contradict each other and create a “dip” in the mids, whose center frequency depends on the capacitance involved.
The red arrow in the pic shows where is this frequency with a 5nF cap: between 500hz and 1khz.
In fact, it’s a subtle variation on Gibson’s Fat Tap / tuned coils...
Don't know if this rambling is clearer than my previous posts. My overloaded mind made my answers wordy and unclear altogether. At least I'll have tried to share something... :-)
Gstring, you're right anyway: theory is not supremely important compared to practical / musical experience.
Pic 1 illustrates what happens when a HB in series has the variable resistor between coils, going to ground (as shown by “Fig 1”, in post 1). As I’ve tried (and failed) to make it clear in my post 11, the resistor “mellows” the signal and “flattens” the resonant peak a bit like a tone control would do as long as its resistance is high. It’s only when this resistance is low that one coil starts to “loop” itself to ground, leaving the second coil working alone. That's where the resonant peak becomes higher pitched and the level much lower...
The second pic shows what happens when a HB wired in parallel has a variable resistor between ONE of its coils and ground (as shown by “Fig 2” in post 1). This time, the control affects essentially the frequency of the resonance, which is logical since it passes the HB from ¼ of its series inductance (in parallel) to half of this inductance (when split): it affects frequencies more than output level.
The third pic shows what happens with a cap in series with the variable resistor, as Gstring has wired it (if I’ve understood correctly what he said)…
...And that’s where my previous explanation was not complete at all. :-/
The 5nF cap has in fact TWO actions in this case:
-it acts like a tone capacitor to ground for coil 1;
-it's also a series capacitor between ground and coil 2 and works as a high pass filter for it.
These two functions contradict each other and create a “dip” in the mids, whose center frequency depends on the capacitance involved.
The red arrow in the pic shows where is this frequency with a 5nF cap: between 500hz and 1khz.
In fact, it’s a subtle variation on Gibson’s Fat Tap / tuned coils...
Don't know if this rambling is clearer than my previous posts. My overloaded mind made my answers wordy and unclear altogether. At least I'll have tried to share something... :-)
Gstring, you're right anyway: theory is not supremely important compared to practical / musical experience.
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