Smal Clone To Flanger MOD

[jupiterboy]

The tonepad small clone can be modded to make vibrato and really extreme chorusing. I was wondering if anyone knew how to slow the delay time down to a flange and add regeneration and possible negative regeneration too. Thank you JB

[Khas Evets]

I think for flanging, you need a shorter delay time.

[ExpAnonColin]

You need to make the delay time lower, not slower.  There is a capacitor nearby the MN3102 that sets the delay time... if you make the value of that cap smaller, the delay time will go up.  Unfortunately, flangers also have regeneration circuits to make them more jet flangy... but you could do a very bootleg version by putting the entire pedal in a very simple feedback loop via a trimpot and tweaking until it sounds OK.

-Colin

[StephenGiles]

You should know that some folks here get "upset" when they see the word "bootleg" - let me see, which one shall I put on.......ah yes, "Found it in the Trash Can" by Boston.....great stuff!
Stephen

[george]

this has been discussed previously - do a search on "small clone flange" and you will see what Mark Hammer had to say on the subject - I recall mention of other stuff that was required as well as what Colin and Khas have mentioned

[Mark Hammer]

Somebody rang?

As correctly stated, the 150pf cap needs to be reduced in value to shift the delay range over.  You will probably want to retain Small Clone functioning too, so the smart thing to do is to stick a 68pf cap in series with the 150pf cap, and wire up a SPST toggle in parallel with that extra cap.  When the toggle is closed, the effective capacitance is 150pf,  When it's open the two caps in series provide an effective capacitance of just under 47pf, which will drop the delay range down to about 40% of original  That won't get you swoosh but it will get you a decidedly flanger-like capability that ought to be able to nail slow Leslie sounds, etc.

Because the filter built around Q2 is there to keep clock noise out of the way, the rolloff used will be appropriate to the clock speed.  Since longer delay times mean lower clock speed, the filter - as is - may be set too low to deliver rich flange tone.  One way to get past that might be to wire up a switchable second set of 39k resistors in parallel with the ones already there.  Close the DPST switch to engage them and the filter rolloff moves up an octave, which should get you a little more perceptible intensity and bite/edge in flange mode.  Although, truth be told, looking at the component values, you may have as much bandwidth as you need right now anyways.  So try it out first without mucking with the filters.

As also noted correctly, flanging assumes some regeneration and the stock SC design, like most chorusses, lacks this option.  As near as I can tell, the sensible place to tap a regen signal from is at the junction of the 1uf cap and 220k resistor, after Q2.  The place to feed it back to is pin 3 of  IC1A from what I can see. Because pin 3 already has a 4.5v bias voltage, no sense in replicating that, so the regen signal should go through a DC blocking cap of some sort on its way back to pin 3.  I'm gonna guess here and suggest that a .033uf and 1k network such as already exists be used for the regen going back to pin 3.  Stick a 100k pot, wired as variable resistor between the .033 cap and the 1uf/220k junction to trim back on regen signal.

Finally, chorusses don't really sound like much of anything when they sweep slowly, so the LFO tends to be fast-ish for flanging.  To remedy that,  you can either replace the 2.2uf tantalum cap with a 4.7uf or even 6.8uf one, or stick a 3.3uf in parallel with it.  That will slow down the overall LFO range so that the fastest and slowest speeds attainable will be noticeably slower, with some overlap between old and new range still evident.  

Most of all, once you've tried this let us know how it worked and what it may or may not be lacking.  Good luck.

[jupiterboy]

Wow thank you all for the tips.I will let you know if I was remotely successful.

[ExpAnonColin]

I can't believe I forgot about changing the filter's frequency.  I am humbled.  

-Colin