Some questions about the caps of the Russian Small Stone or some new mods

[gigimarga]

Hello,

I made a inventory of my pedals and I retested the first pedal that I've modded: a Russian SS with JC Maillet's Univibe mod, vibrato mod and Mark Hammer's phase filter mod.
It seems that my tastes are changing in time, because the vibrato mod seems to me almost useless now (anyway, I am not a big fan of any other tremolo than Tremulus Lune) and the Univibe mod makes the sound too agglomerate (I have an Univibe clone too, so it seems that this mod is a little useless now, too). Only the Mark Hammer's Phase Filter mod is still sounding good for my ears.

Because now I have 2 holes free from the switches, I want to use them with another mods. I've tried to change all the caps from 6.8nF to 3.3nF (as half of 6.8nF) or 10nF (almost twice as 6.8nF), but differences seems to be to me too subtles.

So, my questions is what values to use instead of the stock 6.8nF to obtain a more dramatical effect (for me, SS has a dark (bassy) sweep, so I am interrested to get a brighter sweep)?

Or another new mods, of course....

Thx a lot all!

[gigimarga]

How affect the value of the capacitor the frequency?
If I lower the cap to half of it, which is the impact on the sound?

[puretube]

Why halve or double the frequency by changing the caps???

(when I_ABC can modulate it > 1000:1)

[gigimarga]

Why halve or double the frequency by changing the caps???

(when I_ABC can modulate it > 1000:1)

Thx puretube!

I want to add 2 switches (I have 2 empty holes in the enclosure ), so I think that caps can do that.
Anyway, I am interrested to add a depth pot or a feedback pot or anything except vibrato mod/univibe mod.

[gigimarga]

No ideas?

[petemoore]

  Just search down to Mark Hammers latest ''great mod for almost any phaser''.
 A couple more non-swept phase stages should help increase drama.
   

[gigimarga]

 Just search down to Mark Hammers latest ''great mod for almost any phaser''.
 A couple more non-swept phase stages should help increase drama.
   

Thx Peter!
I've just read the Mark's topic, but it's too complicated. I just want to know how affect the values of the caps the frequency...

[Mark Hammer]

It's a filter.  So, like all filters, as the cap value gets larger, the location where the filter has its action moves lower.

If it is a highpass filter, then the point where the bass is removed moves lower.  If it is a lowpass filter, then the point where the treble is removed moves lower.  It is is an allpass filter, the en point where the maximum phase-shift is reached is also moved lower.  The result of this is that the location of the notches is moved lower.

As puretube mentions, though, because there is an almost 1000:1 range of where the notches mgith be produced (by adjusting the Iabc the "right" way), there is no real need to change cap values to produce notches in a different part of the spectrum.

However, I am not puretube, and neither are you or many other people.  So, what is possible in theory ends up being harder for us than simply leaving the sweep circuitry as it is, and changing the cap values.  Using .0056 or .0047 will move the notches up higher, and using .0075 or .0082 will move them down lower.

[gigimarga]

............
However, I am not puretube, and neither are you or many other people.  So, what is possible in theory ends up being harder for us than simply leaving the sweep circuitry as it is, and changing the cap values.  Using .0056 or .0047 will move the notches up higher, and using .0075 or .0082 will move them down lower.

Thx a lot Mark...that's the things that I wanted to know:

1. I'm not puretube (in some of my sweetest dreams, it seemed to me that the Oracle of Electronics has told me: "You're puretube!"...now the mistery is revealed...he has told me the truth: "You're pure dude!" ).
2. The way that the values of the caps affects the notches (anyway, it's unclear to me why the 3.3nF don't have a much higher sweep...maybe I made a mistake).