HI @ricardopeixoto , thanks for logging the bug. I’m afraid you’re hitting the limits of the Synth design and CPU warnings are there to communicate this.
We support up to maximum 8 voices, but not all combinations of synth engines will perform equally. We could limit the number of voices further and always have optimal performance but instead we introduced CPU high (yellow) warning (just like a computer DAW) to indicate you need to take few steps back… because when you hit CPU overload warning (red) you will get audio dropouts.
PMD and GRAIN are particularly CPU hungry and that’s why they are limited to 2 and 1 voices respectively. GRAIN is special because it’s paraphonic: that means it can effectively play unlimited number of voices which are equivalent to its Density and Grain Size, so those two parameters will affect CPU load also. On the PMD synth engine Array parameter will also have a big impact on performance.
So if you are reaching yellow or red CPU warning, we recommend the following:
- GRAIN: adjust Grain Size and especially Density parameter to a lower value
- PMD: adjust Array parameter or lower the voice count
- If you want to keep higher values of the previous two synth engines because you “need that particular sound”, then lower the voice count on the 3rd synth engine loaded
These are the constraints of the current Synth design and I hope this explanation helps with understanding how to use it without running into performance issues.