Finally I tested through the active EQ. But, I dont like how the blend pot works:
blend_pot.png
At the mid position, the blend sound is very prominent (and I like it most).
But as soon as I turn left/right, there is a very little room for smooth transition between pickups.
The tone abruptly changes towards one of the pups.
I think of buffering the pickups:
But I don't know how the circuit would handle short to ground (end positions of blend pot).
Buffering would handle the pot load and bring back some trebble.
Up til now, I was testing the pickups with no pot load - connected to amp directly.
The blend pot load seems to be 250k || 250k ~125k
blend_pot.png
At the mid position, the blend sound is very prominent (and I like it most).
But as soon as I turn left/right, there is a very little room for smooth transition between pickups.
The tone abruptly changes towards one of the pups.
I think of buffering the pickups:
But I don't know how the circuit would handle short to ground (end positions of blend pot).
Buffering would handle the pot load and bring back some trebble.
Up til now, I was testing the pickups with no pot load - connected to amp directly.
The blend pot load seems to be 250k || 250k ~125k
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Did you used linear pot instead of audio (log) pot ?
Since there's input/output cap in the buffer, ground of blend pot is not a issue.
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Have to measure if it is log.
Might be halfway resistance, halfway zero (to have one of the pups fully on), linear or log...
- Isolated/buffered pickup blending? | TalkBass.com
Some ppl suggest that I use mono potentiometer with the buffer circuit and take the mixed signal from the tapper.
What about losses in mid position that way? Both as db level and some loss of trebble?
Might be halfway resistance, halfway zero (to have one of the pups fully on), linear or log...
- Isolated/buffered pickup blending? | TalkBass.com
Some ppl suggest that I use mono potentiometer with the buffer circuit and take the mixed signal from the tapper.
What about losses in mid position that way? Both as db level and some loss of trebble?
If you buffer the 2 pickups, the whole point is to benefit from the very low output impedances of the buffers. It makes no sense then to route the outputs to (a much noisier) 250K blend pot. I'd suggest using a 25K MN blend pot, which is available from several manufacturers...
Yes you can put the two buffer outputs into opposite ends of a 10k to 25k linear pot and take the blended output from the wiper. It looks fine in LTSpice and I am planning to try it out soon, but I can't say how well it tapers yet.
I ended up using Boss LS2 with FS6 foot switch. With single input, can choose low or high volume, with dual inputs can choose A or B or A + B with different mix levels. Momentary or retain foot switches. Of course if it has to be done inside guitar, would prefer individual buffers as in the schematics. Regards.
p.s. It would work properly buffered, regardles the pot value, right?
The pot is MN pot.
I mean, 250k is too much for the buffer output (noise), but would still blend better?
And there would be more trebble and harmonics, unloading the pups from the pot.
I would like to have option for the brightest tone possible, for slapping. Reducing the treble is easier. Bringing back the trebble is not really possible 😀.
Problem might be shifting the resonance peak with active buffer and alter the tone - there is no load for the pups.
But first I tested the pups connected directly to amp - no pot, active EQ, whatsoever. Only the amp input chain as a load. And I liked it.
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Makes sense that you liked the no-volume no-tone passive approach. The effect of adding capacitance is to lower the resonant peak. You're still using a cable, and it is responsible for setting the peak frequency when you are passive like this, so the peak FREQ is what you're used to.
The important effect you are getting is from eliminating the volume and tone pots. You're bypassing that load, leaving only the (typically) 1meg input impedance of the amp. So not having the potentiometers means you're getting the highest resonant peak you can in passive mode. If you like it--great.
For many people it would be too bright, me included. Having all my string squeaks maximizeded, all the harmonics from the strings I failed to mute/damp with a finger or palm--yuk. Everyone would be saying about me "That guy sound like sh*t!" (Maybe they already say it(?))
Naturally if you want it like it is now but even brighter then you can buffer AND add treble boost in a simple circuit, and you can add a parallel capacitor to reproduce your preferred resonant peak. If you see the audience holding their ears because of the laser beam-like treble ice picks flowing out of the p.a. then you'll know to reduce the highs maybe a hair! Just kidding.
The important effect you are getting is from eliminating the volume and tone pots. You're bypassing that load, leaving only the (typically) 1meg input impedance of the amp. So not having the potentiometers means you're getting the highest resonant peak you can in passive mode. If you like it--great.
For many people it would be too bright, me included. Having all my string squeaks maximizeded, all the harmonics from the strings I failed to mute/damp with a finger or palm--yuk. Everyone would be saying about me "That guy sound like sh*t!" (Maybe they already say it(?))
Naturally if you want it like it is now but even brighter then you can buffer AND add treble boost in a simple circuit, and you can add a parallel capacitor to reproduce your preferred resonant peak. If you see the audience holding their ears because of the laser beam-like treble ice picks flowing out of the p.a. then you'll know to reduce the highs maybe a hair! Just kidding.
The FET buffer I built into my stratocaster operates with 10kOhm source resistor followed by 22kOhm potentiometer.