Bösendorfer Imperial - CPU Multicore

[Duccan]

Hi All,

I am a Pianoteq user which I use with my Kawai CN37 digital piano. With the black Friday deals I took the plunge and bought the VSL Bösendorfer Imperial standard library. The library sounds great, but I have some issues though with the CPU performance. 

I like the Deca-Player preset which uses 4 mics in the library. When playing this preset, I need to increase to audio buffer to 256/512. 256 still has some cracks/clicks. It is still playable, but the issue (or disappointment) I have, is that the Vienna Synchron Player only utilize 1 CPU. When looking in Tasks manager, the other 7 threads do basically nothing, and sit idle. It is possible to utilize all (or more) CPU cores/thread? This would improve the performance so much. It is a pity that the player is a single thread application. Would it use all CPU cores/thread, using a minimum buffer size of 64 would be possible with all mics enabled.

My settings:

• Audio buffer: 64 (just for the screenshot)
• Samplerate: 44100 Hz
• Driver: ZOOM U-24 ASIO (performs better than ASIO4ALL)
• Preload size: 16384 (max due to 16GB RAM)
• Streaming/loading thread: 8 (changing this does nothing)

My setup:

• Zoom U-24 Audio interface
• Intel NUC8i5BEK PC
• Intel® Core i5-8259U CPU
• 16GB RAM
• Samsung EVO 970 500GB NVME drive (M2 PCI)
• Windows 10 Pro (fresh installed yesterday)

It the screenshot you can see that Synchron Player only utilize 1 CPU thread.

[url=https://ibb.co/dKCwB83][img]https://i.ibb.co/0J4RqHW/vsl-cpu-usage3.png[/img][/url]

[Duccan]

Just an idea (still have to test it if it is feasible): Load the vsl vst instrument multiple times in a vst host. Where each vsl vst instance has a different set of microphones. Perhaps by loading multiple instances, the cpu load is divided over multiple cpu cores. (If the multicore feature is correctly implemented in the vst host...). Disregarding the overhead of loading the vst multiple times, it might improve performance.

[Paul]

Hello Duccan,

64 samples will be quite tough on the piano. Increasing it to 128 might double the number of possible voices.

A few options there:

• We actually created the Room-Mix channel to give you a quick possibility to have a great sound with little CPU usage...
• It will also help to turn off Sympathetic Resonance completely.
• Another idea is to lower the voice limit on the EDIT page (#12 and #13)- the intelligent voice stealing will still give you good results.

We'll check which possibilities are there to offer a multi-threaded version of Synchron Pianos, but I think it will still take some more time.

Best,
Paul

[Duccan]

Hi Paul,

Thank you for the reply. I understand that I can tweak the parameters to gain better performance. The only gripe I have is that I think it should not be needed. Not all resources are being utilized properly.

What I have tried, I have loaded the VSL VST three times into Cantible Lite. Where of the first three VST plugins in Cantible there is a single mic setup, and the last one has the two main mics configured. Identical settings as in my first post with the exception that the mics are split over the three loaded plugins.

The results are very good. In the task manager I don't see that a single core is maxed out. Still the first (virtual) core has the majority of the load, but the other (virtual) cores help, and prevent overload. With a buffer of 64 samples there are only a few cracks and pops with loud ff chords. With 128 size buffer I can only reproduce the cracks when bashing non-musically on all the keys.

There is a RAM memory penalty. By loading the VSL VST plugin three times, the increased RAM usage goes from 7.4GB to 12GB. However I am happy, the performance is better than with only the Synchron Player.

Still, if there will be a updated Synchron Player with proper multicore support, I will be happy to try and use that ;-)

[url=https://ibb.co/2vNpjKK][img]https://i.ibb.co/6HBq4ss/vsl-vst3.png[/img][/url]

Regards,

Duccan

[Gustar]

@Paul said:

We'll check which possibilities are there to offer a multi-threaded version of Synchron Pianos, but I think it will still take some more time. 

Best, 
Paul

I really hope this can be accomplished. 👍
CPUs with 8+ cores are becoming more and more common. Users shouldn't really have to compromise with the settings or resort to multiple sample player instances, while only a fraction of the available CPU power is actually being utilized.

[Duccan]

Managed to found another 4GB RAM memory, and plugged in into my NUC. I split the main, and main-c mic in a separated plugin, and the performance are even better. Buffer size @64, and no cracks during ff chords. Weird thing it used less memory than before. But perhaps a reboot did this. It is Windows after all... 

Only thing now is, when tweaking the VSL BI settings, I need to do it four times now...

[url=https://ibb.co/1RYwHby][img]https://i.ibb.co/kqVWYMb/vsl-vst4.png[/img][/url]

[Duccan]

@Gustar said:

I really hope this can be accomplished. 👍 

CPUs with 8+ cores are becoming more and more common. Users shouldn't really have to compromise with the settings or resort to multiple sample player instances, while only a fraction of the available CPU power is actually being utilized.

I agree. 15+ years ago when the quad core and higher went to market, basically all application performed badly due to non-multi-threaded support. But nowadays CPU only increase in core count. The maximum clock frequency has stagnated pretty much. Proper multi-threaded application are a requirement nowadays.