For fear of offending our readers we often steer clear of talking about the basics of audio and music production. However I’ve recently given a member of my extended family an Mbox as a gift and now I realise that there is so much we can take for granted.
So if you’re experienced then this series may be way too fundamental for you, if not, then I hope we can help you.
His first question to me was ‘when I play my guitar there’s a delay when I record, but not on playback.’
That delay is what we call latency, which Wiki defines ‘refers to a short period of delay (usually measured in milliseconds) between when an audio signal enters and when it emerges from a system’.
So whenever we put audio into a computer and then the computer has to process it, depending on the speed of the computer and the complexity of the task we are asking the software to do, latency will take place. Of course the more powerful your computer and the less complex the task the lower the latency will be. Conversely a slow computer that’s already doing a lot will give you a longer latency.
There are a number of ways around this:
- Monitor the audio you record outside of your software, in other words use an external mixer or amp and then mute the channel you are recording so you only hear the live feed with the rest of the track.
- Buy a unit that gives you independent mixing outside the recording software, case in question the new Mbox with its brilliant DSP.
- If neither of these options is open to you then the best thing to do is to record time dependent audio which needs to be in time as early as possible and secondly don’t add lots of effects and virtual instruments until later on in the process. If you do this then you can reduce the buffer settings without worrying about having issues. Pro Tools LE and M Powered actually alert you to this normally by stopping playback. Some systems do not stop, but there is a high likelihood that your recording will have pops and clicks and drop-outs. So although the ‘increase buffer size’ pop up in Pro Tools can be annoying it does save you a whole lot of hurt later.
Hardware based systems such as Pro Tools HD will not have this problem, but any native system will have some element of latency.
So next time you record and there’s a delay, now you know why it happens and how to fix it!