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Frank B
02-20-2016, 02:09 PM
Hi,

i tried the chorus-effect. Is that really a chorus ? (buggy??)

It sounds more and more "digitally" the more "num_chorus" or memory i add. Or, is this intended ?

Frank B
02-20-2016, 03:08 PM
...hm... the sourcecode shows only delays, no pitch shift per "voice", this can't work (obviously, as you can hear)
What ever this effect is, it's not a chorus :-( Perhaps the same can be done with the delay-effect.

B.Jacquot
02-23-2016, 12:09 AM
Looking over the source, yeah, that looks like a set of static comb filters. Something like the multi-tap delay line followed by a mixer.

Take a look at the Flanger class. It has sinusoid modulation and interpolation. Flange with slow modulation and overall delay of 25-ish milliseconds moves into chorus territory.

el_supremo
02-23-2016, 12:17 AM
When I wrote the chorus and flange effects, I used this as a guide:
http://www.cs.cf.ac.uk/Dave/CM0268/PDF/10_CM0268_Audio_FX.pdf
It says that chorus doesn't use modulation so I didn't try any. I couldn't find anything else which explained how to get those effects.

Pete

adrian
02-23-2016, 04:24 AM
all you need to know about chorus (http://www.electrosmash.com/boss-ce-2-analysis#link11)

evidently a lfo modulates a clock signal, giving variable delay times. From the page ....

"The chorus effect is created by the slow modulation of the delay time using a Low Frequency Oscillator (LFO). As the LFO cycles, the delay time goes up and down and therefore the delayed audio pitch slightly shifts up and down."

Sounds a bit like how imagined a flanger would work ....

the delay is a bucket brigade device (whatever the hell that is)

You don't happen to have MIJ HM-2 source-code??