"Independent" vs. voltage divider volume control, into different loads, with graphs

[earthtonesaudio]

Hi all,

I did some simulations of a "pickup" going into either a voltage divider volume control, or an "independent volume" style control, and simulated the frequency response through a "cable" into 3 different load resistances (different input impedances for an amp or effect).
PDF file here

The schematic is on the last page. V1, R1, L1, C1, and R8 represent a guitar pickup. R12/R13 represent the volume control. L2 and C2 represent some length of coax cable, and R3 is the load impedance of whatever the guitar is plugged into (i.e. an amplifier).

I did two plots for each load resistance value (1M, 100k, and 10k). The first of each set of two is the standard voltage divider as shown in the schematic. For the second plot I connected the pickup to the junction of R12/R13 and took the output from the top of R12, a configuration known commonly as "independent" wiring.

I'm sure my sim could be improved, so I'd like some constructive criticism if my "pickup" or "cable" values are wrong, or if I should add anything else. I might redo the plots with a log Y axis, if it makes it a bit easier to read.

[kg]

i'm having trouble comprehending the goal or advantage to the "independent" topology. i've not heard of it before...

[Albert Kreuzer]

I think he is referring to a Jazz Bass style volume control, where the slider of the pot is the "input".
"Voltage divider" would be conventional wiring (slider = output).

[tmenss]

Or perhaps like wiring a Strat with 50's style Gibson wiring as opposed to the standard Strat? This may be of benefit wiring a Lemme style Cap switch before the volume control and tone control...if there's any reason to do such a tone circuit.