Analogman Chorus Schematic + Mods

Started by POTL, October 27, 2017, 06:21:32 PM

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POTL

Hello
I'm interested in the Analogman Chorus circuit - I know that this is an EHX Small Clone circuit from the Tone Pad site, but it has minor changes, who is aware of these changes, what has Mike changed?
Also I'm interested in the following fashion
1) Mix - in the left position it is completely pure signal, in the right position it is a chorus (a variant with three modes, clean-chorus-vibrato is not interesting)
I understand that this should be in the mix section, R5 / R21 but how is it better to implement it?
As in the Boss CE-2B?
2) Delay Time
As I understand it, the only option is to replace the R32 with a fixed resistor and a 100K potentiometer in the series with it?

Mark Hammer

To adjust the wet level and go from normal chorus to something subtler in the background, insert a variable resistance in series with R21.  I'd suggest 50k or 100k.  Alternatively, consider using a 3-position toggle to select between the stock R21 value or either of two larger resistance values.  If you make R21 82k, a 3-position can add in 68k in parallel with R21 for 37k or add 27k in prallel to make 20k (or very close to it).

To change the delay range, replace C14 with a 150pf and 220pf cap in series.  Wire up another 3-position switch, with the common connected to the junction of the two caps, and the outside lugs connected to the other end of each of the two caps.  With the switch in the middle, the two caps are in series, yielding an effective value of around 82pf, and a shorter delay range.  This makes for really nice slow Leslie tones that fall in that magical range between flanging and chorus.  In one of the side positions, the switch bridges the 220pf cap, restoring the stock range.  In the other side position, the 150pf cap is bridged, making the effective capacitance 220pf.  This gives a longer delay range and a "thicker" sound.

Note that at longer delay times, you'll want to turn the depth down,or else you'll experience too much pitch wobble.

POTL

#2
Thank you
I found these modifications on madbean.
The method of switching capacitors looks very global, on hearing it seems that the shape of the wave changes(VFE Choral Reef toggle switch).
What about the option with a potentiometer in the series with R32 as in the project by reference (R12 + POT).
http://www.madbeanpedals.com/projects/VFE/VFE_ChoralReef.pdf
VFE product reviews are horrible and do not give an understanding of the work, I need to do this like this (video below).

Mark Hammer

For my money, a continuously variable time control likely won't achieve that much more than if one used it at 7:00, 12:00, and 5:00.  Players seem to feel a compulsion to have continuously variable controls; as if they were giving up something by having only 3 presets.  Sometimes you need a continuously variable control, but sometimes it adds little.  This is one of those latter cases.

POTL

Quote from: Mark Hammer on October 28, 2017, 02:24:09 PM
For my money, a continuously variable time control likely won't achieve that much more than if one used it at 7:00, 12:00, and 5:00.  Players seem to feel a compulsion to have continuously variable controls; as if they were giving up something by having only 3 presets.  Sometimes you need a continuously variable control, but sometimes it adds little.  This is one of those latter cases.


Thank you
How will the BBD try to collect both options.
So it will be more correct.
But still, am I right? Potentiometer 100K connected as in the scheme Madbean will give me the result as in the video?