Chorus to flanger?

[col]

I'm about to build the Corrral Chorus from Tonepad's layout and it's the biggest stripboard layout I've done so far! Before I build it is there any way to put in a mod section to also use this as a flanger? Is it simply a case of increasing the pot in the LFO section or would I have to affect other parts of the circuit as well?
In J Chatwin's book "Advanced projects for the Electric Guitar" an analogue delay is converted simply by using an LFO between 0.5Hz and 5Hz and this seems to be the only control for the flange/chorus/vibrato.

[goosonique]

http://diy.erikhansen.net/ce2.htm

[Mark Hammer]

1) The fundamental difference between a chorus and flanger is the range of delay times covered.  Reducing the small cap connected to the clock chip (MN3007) will shift the overall delay towards zero.  Note that there are some hard limits to how much this cap can be reduced, but dropping it to 27pf is not outside the realm of the possible.

2) When clocks have a lower frequency to generate longer delays (as in the case of the chorus), the lowpass filtering is set lower so as to keep clock whine out of the audio output.  This will limit how robust the flanging effect appears to be as it sweeps upward.  To switch back and forth AND get the max out of each type of effect, you'd probably need to change the filter cap values.  Feasible, just complicated.

3) While both flangers and chorus sound good with faster sweep rates, chorus sounds awful at the sorts of slow sweeps characteristic of flangers.  Consequently, conversion also involves changing the LFO range.  Also feasible, but a nuisance.

4) The CE-2, like all choruses, has no option for introducing regeneration.  Flanging can still sound pleasing and musically valid without regeneration, but many folks like to use it.

So, you CAN turn the CE-2 into a flanger, but getting somethingt that sounds as nice as even a humble Boss BF-2 would require a lot of mods and switches, which would likely result in far too many leads running here and there to produce a noise-free sound.  Better to build a chorus AND a flanger separately.

[col]

Thanks for the info. I think I'll just build it as the chorus and build a flanger separately sometime in the future. It was the book that gave me the idea that I might be able to produce one device that'll do both. I did a stripboard layout for John Hollis's (I think I spelt it right, if not I apologise) Ultimate Flanger a while ago but it was even bigger than the one I did for this which is 50 holes by 25 strips. I'll see if I can get it smaller.
Once I've built it and checked it I'll post it here but it'll be a week or two as I'm a bit busy at the moment.

[Mark Hammer]

Hey, the first thing I do when I get a chorus is to install a toggle switch to select shorter and longer delay-time ranges, so don't bump it completely from your list of things to try out.  It's a question of whether the chorus-to-flanger adaptation can live up to the best of what a dedicated flanger can do and sound like.

I'm reminded of a "pizza" someone made when I was sharing a big house with 8 other people some 30 years ago.  It was flat and round, but it had no cheese, had a coarse whole wheat crust, and broccoli.  True, more pizza-like than pot roast, but not exactly pizza.  A simple range-shift CAN liven up a 2-knob chorus (and one should keep in mind that the "character" of many commercial chorus pedals is partly a function of the delay range the manufacturer has selected; some are longer/shorter than others).  Just don't expect it to go "Poof!  I'm a flanger".  As noted in my earlier post, that would require a number of other changes to do properly.

[oldschoolanalog]

Within any decent 4 knob flanger there are a wide variety of very nice chorus sounds and textures. It's just a matter of learning where those settings are (the fun part). If you haven't started your build, consider building a flanger (the real fun part!).
Just a thought.
osa