That is really interesting. I replicate now your test with x2 oscillators and for me it is the opposite:tumface wrote: Sun May 25, 2025 8:14 pmI tried your test, but slightly changed, on my M1 Pro Mac. 48khz, 128 sample buffer.vanerio wrote: Sun May 25, 2025 7:38 pm That's your case, not everyone's.
My test: x3 osc (unison x8) -> 24 dB/oct lowpass filter -> x4 notes chord
Results:
Serum 2: 18 % CPU
PhasePlant: 13 % CPU
MSoundFactory 1 % CPU or 2 % with oversampling (yes, 1%, 18 times less)
2 saw oscillators at 16x unison, into a clean 24 db/oct lowpass filter, playing 4 notes. I just eyeballed this on Live 12's CPU meter. I could take more accurate measurements using Bitwig's DSP graph, but I think this is good enough for a rough approximation.
Dune 3: 2%
Hive 2: 2%
Phase Plant (have to use 4x osc, because of 8x unison limit): 7%
Serum 1: 27%
Serum 2: 12%
Maybe Serum 2 added a smarter unison implementation?
Notes:
- Dune 3, Hive 2, and Phase Plant have dedicated saw oscillators. Serum 1 and Serum 2 don't have dedicated saw oscillators and are always in wavetable oscillator mode.
- Hive 2 is set to "Clean" mode to more closely match Dune 3's default behavior, which is also clean. "Normal" mode uses more CPU than Dune 3. (But choosing a more expensive filter in Dune 3 also makes its CPU go up.)
- Phase Plant's normal (non-non-linear) filter cramps and doesn't sound great, unlike the filters in all of the other synths here.
- Phase Plant's CPU starts going up as soon as you add an envelope modulator for the filter, which isn't the case for Hive and Dune when using the fixed-routing modulation envelopes. Using the mod matrix probably makes the usage go up, though it was too low to measure. Serum 1 and 2's usage goes up less per envelope modulator than Phase Plant. The mod matrix probably gets more expensive in Dune 3 if you set its modulation rate to audio rate.
Serum 1: 20 %
Serum 2: 22 %
I am at 2048 samples buffer...so 128 would fry me up some potatos for dinner.
Edited: I update the CPU % values, as my previous test was with x2 oscillators (x8 voices), now they are (x16 voices). Just 1 instance is pretty hungry in my system even with huge buffer.
This is in line with my previous testing: all my Serum 1 presets require more CPU in Serum 2.
