Cpu overload in some very few presets

[francoise]

It's not a crippling issue but one I find a bit mind boggling.

On Windows 11 with a i7-7700 CPU, I sometimes get CPU overload (right lower corner) in Analog Lab V with some very few presets. More precisely in the nice Art of dreaming bank, the Derealisation preset, a multi involving Mellotron. Same with two other presets involving Mellotron.
In full polyphonic mode, AL CPU indicator can shoot up over 100% (with audio noises). It coincides with an overload in the 5th core (of 8 cores) in the Windows CPU ressource monitor. It seems to be a CPU problem, not a memory problem. It was more conspicuous in Windows 10.

But Mellotron is a sample based intrument not involving intensive synthesis processing. To me, this is strange. Why should CPU be involved.

As I say, it's not a crippling issue: I simply reduce poliphony to 3-4 notes. But I almost extended the memory from 16g. to 32 g. thinking it would alleviate the issue.

[LBH]

Hello,

You don't tell which buffersize and samplerate you use.

I assume you talk about the standalone version.

I don't have the Soundpack/ preset you mention. So i can't test it.

I can suggest you check if Multicore is enabled in the Settings in the right panel.

Mellotron has some processing going on to make it emulate Mellotron tape.

No matter what, then i do think CPU load is something Arturia have to see, if they can optimize more.

[francoise]

Thank you for answering, LBH. Good questions:

Sample rate 44100, buffer size: 512 (possible range 16 to 1024). Scarlett 4i4 3rd gen.

Yes Analog Lab V standalone but I get the same result in Reaper.

Multicore is ON.

I checked the guilty Mellotron preset (Derealisation) samples: 2 x 1.2 mb and one 1.88 mb. Not really huge.
I don't get this overload with other Mellotron presets. Sometimes they can get to 40-50%. This one has a slow and long release. Maybe with polyphony, the samples pile up. It should be a memory problem but as you say there is some  processing to be done. Anyway it's not crippling but I almost bought RAM thinking it would solve the problem.

Thank you once again.

[LBH]

Your welcome francoise,

I think it sound very bad, if you have issues with those soundcard settings and that CPU.
512 samples is a huge buffer to me when playing. I prefere 128 samples or lower, and not over 256 samples when playing with a samplerate at 48000 Hz. I will only use 512 samples buffer, if i'm forced.
I run 24 bit.

Arturias new minimum requirements for CPU is as huge as 3.4 GHz base frequency (4.0 GHz turboboost). So they are aware of the huge CPU usage some sounds have.
But i would say your CPU live up to the requirements, even if it's around 5 years old. Perhaps you can ask Arturia about that.
It's not good if some designers presets use to much CPU.

Having many voices playing at the same time will use more CPU. So long release times can cause many voices to be playing.

I assume your Focusrite soundcard run okay.
I also assume you have your PC set to High Performance mode, and your PC does'nt use lots of CPU resources for other things.
But you can check things like that, if you wish.

You can also try to disable hyperthreading in the BIOS to see if that make a difference. You can allways enable it again if not.

You can also try if your system work better with a 48000 Hz samplerate, even if it theoreticly should put a little more load on the CPU.

I'm not sure which other instrument there is in your multi presets.
Also i don't know how many voices you have playing at the same time.
But this is also a thing to check.

Perhaps you allready have tried all this.

I can't rule out something strange is going on. I have to be able to check then. But again you can ask Arturia.

I'm interested in CPU usage.

[francoise]

Hi LBH,

I can try 48000 hz but theoretically, it's should be more demanding. 512 is a huge buffer but I usually play with drum, bass and piano in standalone between 70 to 120 bpm. It's reactive enough.

Hyperthreading? It's worth trying. The i7-770 is 4 cores and 8 threads not 8 cores.

I run Windows 11 bare bone (all gadgets and notifications off, minimum animation, no useless background processes). It's quite reactive.

The other instrument in the multi is Farfisa, I recreated the Mellotron part in non multi setting and got the same result.

Yes, I'll summarize the issue and ask Arturia. I don't really bother them often except when I got two order pending twice. It seems Credit Mutuel doesn't like payments from linux.