Rules of thumb for ASIO Guard


I read a little on ASIO Guard and how it works, and would like to understand how to optimize it for certain situations.

  1. When I’m recording a live instrument or live MIDI should I set ASIO Guard to low or completely off so that there is a lack of latency between audio processing and the armed track?

  2. Similar for when I want to apply automation, for the same reason?

  3. If I’m not doing any live recording or live automation, should the ASIO Guard be set to high for optimal CPU performance?

thank you

  1. No. Asio guard only affects tracks that are not live monitored or record armed. That’s the whole point of it.
    As soon as you record arm the track or turn the monitor on it switches to normal processing path. The rest of the tracks are pre-processed with higher latency to save resources.

2)That’s questionable. You can record automation without arming the track which means it will be affected by asio guard. Try what works best for you. I leave it set to high all the time. But I usually write automation instead of recording it.

Hi and thanks for your response. That was sort of my point - live instrumentation or recording situations are not passing through ASIO Guard, but the rest of the audio is - doesn’t that create a mismatch in latency - and therefore best to have ASIO Guard set to Low or off when in these situations?

No it is all compensated. So high here always. Not that there is much difference between low to high with my RME card. Asio guard Off does make a difference though.

No! This is what ASIO guard is designed for. The already recorded material has a known processing requirement so ASIO guard makes sure to get it ready ahead of time (if possible, depending on real time requirements) to minimise real time stresses on the system from the new material being recorded. If you turn ASIO guard off the system has to process everything in real time and hence you’re more likely to get audio drop-outs.

The Knowledge-base article probably explains it better!

Thanks for explaining! So, just trying to understand, are you saying that merely turning ASIO guard on (not even while playing back or recording) uses CPU cycles because Cubase is processing existing tracks to “get them ready” for recording other tracks?

If so, I think I finally understand. Except for answering, “well, why not set it to Maximum at all times?”.

I don’t know how much it gets ready before you press play…an interesting question.

Except for answering, “well, why not set it to Maximum at all times?”.

… another good question. :wink:
I think I do have it set to maximum but I think I recall an article saying the efficiency of it varies from system to system depending on this and that (only more technical) so you have to find the right level for your machine.

If so, I think I finally understand. Except for answering, “well, why not set it to Maximum at all times?”.

I think the main reason might be writing automation.

When you enable Write automation you don’t need to record arm the track. Therefore it will be processed by Asio guard. The added latency may be too much to record the automation efficiently.

The rule of thumb?
Set it to max and forget it.
As misohoza says there is a possible problem with automation but only when input manually from external controllers and most people are never fast or accurate enough for that to become a practical problem.
If they need that level of precision they tend to “Write” or correct it by editing by hand (Mouse) and that’s not a problem.
There are other small graphical things you can notice but as yet no user here has yet ever mentioned them, so I say nothing.


Thank you all.

So, in a nutshell…
Setting the max ASIO Guard setting ensures as much strain is taken off the CPU from normal audio processing/playback activity?

Not scientific but when I read up on it I thought “set it to max and forget” and so far my system has been rock solid and has managed
everything I throw at it. It is not even current by quite a big margin. (100+ tracks 300-400 plug ins and 65pct ASIO use) Seems to work well.