changing Op volume by MW & LFO crackles

Posted on Sun 21 Mar 2021, 10:31 AM

i made a couple of simple 2 op voices to illustrate this issue. its a basic 2 -> 1 configuration assigning mod wheel [or LFO] to op2 volume. raising the mod wheel will introduce op2 as the modulator, or for the LFO voice just press a note to hear the effect.

its most noticeable from middle C down, as the lower frequencies dont mask it so much. it sounds like a crackle, most likely its caused by zippering or something of that nature?

this crackle doesn't happen with EG sweeping op2 level, its a nice smooth transition as expected. theres also an example voice with a clean op2 sweep for reference.

i tested this with different levels of digital gain, including very low, and it was still noticeable, so its not a gain issue.

Zipperring.efm

KODAMO

Posted on Sun 21 Mar 2021, 03:17 PM

This is due to LFO resolution. They don't have any smoothing to allow to use noise waves with distinct steps. This has the side effect of making zipper noise in some cases, mostly if you use them to modulate the volume of a loud modulator.
For this specific case we suggest using an envelope loop on the modulator. Envelopes are fully smoothed out.