Re: Strat treble bleeding mod

Tony Done <tonydone@xxxxxxxxxxx> wrote:
"RichL" <rpleavitt@xxxxxxxxx> wrote in message
news:gOqdnSJKAb1pfcHXnZ2dnUVZ_j-dnZ2d@xxxxxxxxxxxxxxxx
Tony Done <tonydone@xxxxxxxxxxx> wrote:
"GoodMan" <StratWiz@xxxxxxxxx> wrote in message


news:94fd8ad8-951a-4fda-a38a-bc3da2b20b1d@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
For Strat treble bleeding mod (0.002uF cap & 100K Ohm resistor),
what brand & model of cap & resistor do you recommend for best
quality?
Thanks,
SW

Can anyone tell me why you need a resistor? I've done a few and just
use a polyester cap, about 0.001microF IIRC.

Tony D

Depends on what you want out of it, I suppose.
In my mind, the objective is to retain the same EQ curve regardless
of the volume setting. You get part-way there with a cap in terms of
treble retention but if you do the calculation you'll find that the
bass drops faster than the treble as you lower the volume with just
a cap, plus the resonance peak shifts to higher frequency. Adding a
resistor in series pretty much keeps the resonance peak from moving
but you still have the bass dropoff problem.

I get *really* close to getting an EQ curve that doesn't change shape
with changing volume by using a cap, a resistor in series with it,
and another resistor in parallel with the other two components. See
the right-hand portion of schematic and component values, which were
chosen to match the pickup and pot resistances on the custom guitar
I had made and for which I designed the circuitry:

http://www.geocities.com/rpleavitt/New_guitar_schematic.pdf

(There's lots of extraneous stuff here related to being able to put
the pickups in series and in parallel, and in or out of phase with
respect to one another.)



I think I follow the argument. - If you just put a cap across the hot
and wiper of the volume control, the EQ curve will inevitably change
at different volumes, whereas if you use the right combination of
caps and resistors the same EQ will be maintained over the whole
volume range. I don't think I'm that fussy, all I'm trying to do is
prevent it sounding dull at low volume, The effect which is quite
striking in my OLP bari, SD Jazz pickups but I can't recall what pot
values I used in it, I would think 500K.

Tony D

Yeah, your interpretation is correct. But I decided to get really
*fussy* with this guitar, because in a lot of situations I've got things
set up so that with the guitar volume control is maxed out, I'm running
pretty distorted, but I wanted a situation in which, when I backed off
on volume, things would clean up in such a way that the sound was as
rich tonally as if I had the volume maxed out but the amp set to clean.


.

Relevant Pages

  • Re: DIY set up?
    ... On 11/5/2011 2:55 PM, Tony Done wrote: ... interested I guitar mechanics? ... and many tube amps even when it's off and unplugged. ... NOTHING on the order of changing that cap. ...
    (alt.guitar.beginner)
  • Re: add on ear joy
    ... horrendously complicated because the cap charges through ... AFAIK they just give a maximum capacitance. ... A graph of capacitor current over time after power-up, ... resistor to be able to use very large filter capacitance ...
    (rec.audio.tubes)
  • Re: The KISS AMP: a progress report
    ... supply topologies and in particular how a choke input works or why it ... you appear to think that a resistor will give off ... the conventions guiding SE amp design towards the desired result. ... 'cause if that cap should fail, ...
    (rec.audio.tubes)
  • Re: Strat treble bleeding mod
    ... what brand & model of cap & resistor do you recommend for best ... use a polyester cap, about 0.001microF IIRC. ... Tony D ... I don't think I'm that fussy, all I'm trying to do is prevent it sounding dull at low volume, The effect which is quite striking in my OLP bari, SD Jazz pickups but I can't recall what pot values I used in it, I would think 500K. ...
    (alt.guitar)
  • Re: Best-shielded SMPS inductors?
    ... from the output of the cap multiplier and the AC feedback from its ... The hysteretic buck design is mostly based on board area--I'm ... Why did you put a resistor ... Optics Electro-optics Photonics Analog Electronics ...
    (sci.electronics.design)