5 posts / 0 new
Last post
Micgees
Micgees's picture
Offline
Joined: 12/15/2013 - 13:43
Filters

why do the filters in caustic devices not cut all the way out...Cutoff is exactly that when all the way left the tone should be gone...but for some reason none of the device filters can achieve this.

nitro27
nitro27's picture
Online
Joined: 10/11/2015 - 18:27
Synth Secrets is recommended

Synth Secrets is recommended reading for everyone everywhere.
https://www.soundonsound.com/techniques/further-filters?amp

A real filters sharpness is defined by dB/octave, so every octave above the cutoff is reduced by that amount. A filter of infinite dB/oct, where every frequency above the cutoff is gone afaik doesn't exist in a meaningful way? Or maybe I'm misrepresenting that. Anyway, they definitely aren't used in music very much.

So Caustic uses a few kinds of filters, all based on real filter circuits, and they generally are 12dB/oct, sometimes 6 or 24, but never infinite.

Combine that with the fact that the bottom of the scale ISN'T 0Hz (again not reasonable in real electronics,) but probably like 20Hz or something, and you see why setting a filters cutoff value to zero doesn't entirely remove the sound.

I really really like filters and probably didn't explain that very well. Sound on Sound does a better job, check that out.

I make Chillout Electronic Music, and sometimes Ambient. http://floatingbeyond.tk
https://soundcloud.com/floatingbeyond

JHSound
JHSound's picture
Offline
Joined: 06/04/2015 - 11:21
The simple thing I learn from

The simple thing I learn from Nitro's link is that the cutoff point is the point where the frequencies start being cut. Frequencies above it don't disappear instantly, they roll off.  Since it isn't reasonable to start at 0Hz (can't divide by 0), anything higher than that will still allow a small amount of even higher frequencies to exist as they roll off.  If cutoff was 20Hz, the gain/output at 40Hz would ber halved, not zero.

mike
mike's picture
Offline
Joined: 12/18/2011 - 15:53
yes, it's the slope and the

yes, it's the slope and the more you cut, the higher anti aliasing you need to remove artifacts in the harmonics.

More processing means more CPU and when Caustic was developed Android was an infant and Rej had to optimize.

EDIT: The point I was making is that rolling off that last bit of signal is even more processor intensive as well as the above limitations of the creamy feel of really nice filters.

Furious5
Offline
Joined: 12/15/2017 - 03:31
Just use the machine's own

Just use the machine's own filter + a filter as insert effect..