VST and CPU performance issues

UHE is now closed. For Technical Support from Ableton, please go here: http://www.ableton.com/support
Posts: 1191
Joined: Tue Oct 26, 2004 11:32 am
Location: UK

VST and CPU performance issues

Post by headquest » Sun Jan 02, 2005 6:36 pm

I am hoping that somebody here might be able to help me or clarify the source of my problems with Live 4's audio handling, CPU hit and VSTi.

I've done a test just using Live 4 and Tracktion, brought on by my growing concern/disappointment in Live's audio performance and CPU handling. Overall I found distinct differences between the two programs in their audio performance, as well as in their CPU usage (although this may be down to inaccurate meters in both or one of the programs?)

I put together a track using a simple audio drum loop plus four MIDI channels, featuring 2x Pro53, 1x FM7 and 1x B4, all fed on a bus through 1x Ambience.

In Live 4 the CPU hit 80% + and audio cut out and the program ground to a complete halt. I repeated the exercise adjusting the CPU/quality knob on Ambience to 50%, and this time Live's CPU read around 65%, but audio still stuck and the program froze.

In Tracktion, the CPU hit around 60% (without even using freeze) and audio streamed without a glitch. This was without ajusting Ambience's CPU load. When I froze the four MIDI tracks, CPU reduced to about half.

Also I am finding that audio recording directly in Live doesn't sound very good to me. Again I'm not sure why. But I get artefacts and clipping even when the level meters are well below peaking.

I have no idea why Live 4 is proving bad for me in this respect, but I can only use it by bouncing down each track one at a time. In effect, this makes Live 4 great for preparing (whether sequencing in MIDI and bouncing, or whatever) and playing back audio loops in real time, but pretty useless to me as a production tool.

Am I missing something or are other people experiencing the same issues with Live 4? I don't remember having such issues with audio performance or VST effect hanndling in previous versions prior to MIDI editing.

Please advise...

Posts: 11
Joined: Wed Jun 16, 2004 8:47 pm
Location: NC, USA

Post by DHR53 » Tue Jan 04, 2005 2:01 am

Hmmm... My experience on the Mac has proven to me, that Live 4 is just not very well optimized for it's new role as a full fledged DAW... I wish it was better, but it really is only usable with it's internal FX, and some audio tracks... and a few really well optimized AUs, like Absynth, FM7, and say, Pro-53... I'm getting 3-5 audio tracks, and 3-5 midi tracks, with the built-in FX on 5 returns... A compressor and EQ on the Master... This runs with 7-9 clips (session view) at between 35-50% cpu. And that's on a Dual 2gig G5 with 2.5 gigs of ram!! If I try and use external FX, like Roomverb M2, or PSP nitro, and or some other plugs such as Imposcar, Chameleon etc. It gets ugly real fast... Arturia's stuff is unusable... Really, you can't make very complex music, if you can't use more than 2 instruments! I'm assuming the problem lies in it's origins as an audio app, and the fact that there is no optimization for dual processors... I don't know how people with a laptop are using it?? If I can't do better than what I'm running with a dual G5?? Maybe it's better on the PC side?? But on the Mac, it's just not there yet... I love the app, but it's just not worth buying expensive plugins and instruments, that you can't run without constantly bouncing and rerecording tracks as audio?? I may just give up and go back to Reason 100% :roll:

Posts: 665
Joined: Wed Dec 22, 2004 2:51 pm

Post by Macrostructure » Tue Jan 04, 2005 11:18 am

Live 4 uses an outrageous amount of CPU compared to other aps. I have been telling Ableton this since it came out. They have consistently given me evasive answers and now just ignore me. Clearly the issue lies at the heart of the core coding and they cannot resolve it.
Furthermore, some VSTis cause Live's undo feature to stop working.

Serious users of MIDI and VSTis should really look elsewhere.

Posts: 1191
Joined: Tue Oct 26, 2004 11:32 am
Location: UK

Post by headquest » Tue Jan 04, 2005 8:01 pm

Thanks for the responses.

That's bad news though :( - I really hope that if this is a general (and serious) problem they will find a way to resolve it and optimise the program better as an all-round music production environment that can handle VSTs and MIDI tracks effectively and efficiently.