Tips for saving CPU

[sburke1]

I've recently been preparing a couple live sets for an upcoming show and am worried about CPU. The main reason is that I want to use a lot of fx, and do some live looping at points which needs a low buffer setting which makes for more CPU.

The first thing I am doing is setting up a couple huge, instrument racks. (since my background is playing keys)

The first one I am making is simple, 8 soft synths. All of their bypass buttons are assigned to macros. The macro map is edited to where the devices only turn on at 127. This way CPU is held low because I will keep all the instruments off that I don't want.

So does anyone has any other ideas for saving CPU on stage?

[Angstrom]

I would look at the softsynths and see which, if any, could be multisampled and run in Sampler instead. 8 notes on a fancy softsynth can clock up a nice CPU overhead of something like 20% , while the same thing in Sampler might be 5%

On stage it's hard to hear nuances in synth sounds, at least every rig I ever played through wasn't very hi-fi and the room adds a further blurring to the audio. So I tend to sample any pads, or sounds that do not specifically rely on some dynamic modulation component of the parent synth.

So, the audience probably won't notice if you use a flat sample of that Absynth pad sound, or that fancy Tension Santoor, plus it might just make you feel more relaxed on stage.

[sburke1]

your right, i will do that!

one CPU thing I have been doing is that I bounce stems to MP3 not wav. that has saved CPU. any feelings on this? I dont hear a drastic enough quality loss to be up in arms about it but I know it is not ideal.

I play in a electronic/pop band so I run linear sequences, bgd vox, etc for shows. triggering scenes filled with loops would be funner but I dont want to worry about screwing up the form and ruining the song. I see that if I bounced small loops and triggered scenes I would probably be better off CPU wise.

Does anyone ever save whole tracks filled with dummy clips and bring them into your session on stage, then use them, then delete, and repeat so you never get bogged down?

[Angstrom]

one CPU thing I have been doing is that I bounce stems to MP3 not wav. that has saved CPU. any feelings on this? I dont hear a drastic enough quality loss to be up in arms about it but I know it is not ideal.

That's actually pointless and is not saving CPU
Live does not decode MP3s in real time, it gets all your referenced Mp3s and decodes them to a temporary cache location as defined in your preferences. It does this so it can warp them in real time which it cannot do with a compressed file.
So you are wasting your time converting to MP3 as they just get converted back to great big waves again.

Better to save your own waves and keep control of the quality and your disk streaming location. You are in fact increasing disk usage by using MP3 !

[sburke1]

thanks man, that will help alot.

i was getting really bad cpu from just loading in 6-8 wav stems for our songs, all linear 3-4 minute wavs. The reason I separated them was because I wasnt sure if I wanted to leave in things in the mix like aux percussion, or to have flexibitly when my bass doesnt show up. That lead to horrible CPU and now I have to committ and bounce the stem to one track, which limits the amount of effects I can do.

I had thought the mp3s made it better but now I will check, im sure your right about the issue.

[sburke1]

just thought of using 16bit to save space. so do you make everything 16bit to save space rather than 24 bit?

the ableton manuals says Avoid using samples that are at different sample rates within the same project." I'm assuming that bit depth doesnt have to be the same over the whole set though.

[sburke1]

I also just figured out how to change bank presets on soft synths with dummy clip automation in order to save CPU and time by easily triggering different sounds.

[machinedelmorte]

could you tell me step by step how you did it.

[sburke1]

now that I look again, i am not sure if you do this for every vst. this works for the mtron ,which I had done. I will show you how to do that. I think it depends if the synth allows you to do it(automate bank changes)


- make a midi track
- add a vst or au instrument (mtron)
-double click on a clip slot to make a blank dummy clip
- hit E for envelopes, and go to mtron
-I then automate "bank"

[machinedelmorte]

thanks. I will try it and let you know.

[sburke1]

I just discovered I could freeze a track.....and still trigger clips. I was assuming that the freeze would only be good for arrange view linear sections. This will save tons of CPU.

[kruko]

one CPU thing I have been doing is that I bounce stems to MP3 not wav. that has saved CPU. any feelings on this? I dont hear a drastic enough quality loss to be up in arms about it but I know it is not ideal.

well, sorry to rain on your parade, but the mp3 is a compressed format, which means you actually use MORE cpu to decode (play) those files that wav files. by using mp3's you will only go easier on your hard drive, not CPU.

[sburke1]

yep, saw that above

[Da hand]

If you are not using the inputs on your sound card, then turn them off in Live's preferences. This will save you some CPU.

[Kristijonas]

I'm dreaming that Ableton will add something like "Activity monitor" or "Proces viewer" one day, which would help to find out where exactly CPU power goes easily