Lower Session CPU Usage With Enso
This tutorial illustrates using Enso Looper by Audio Damage, Inc. to reduce heavy CPU usage one can encounter using synth apps and plug-ins in apps such as AudioBus, AUM, and Ape Matrix.
Summary
The method is summarized as follows:
- Add Enso as an FX to capture output from an app
- Record a loop of some measures long
- Automatically begin playback of the loop
- Remove the recorded app from the session
NOTE: This is trading flexibility and RAM usage for CPU usage, so it may not be appropriate for many use cases. An iPad won’t be able to handle long loops, or more than a few instances before becoming unstable. But it can be helpful if all of a sudden that killer jam is developing crackles.
Video
Here’s a brief YouTube video if you prefer:
Step by Step
Let’s assume you have some sort of sequencer (we’ll use Atom Piano Roll in this example) sending MIDI to an app (we’ll use Arturia iSEM), and possibly some heavy FX in the chain. Our setup looks something like this:
Atom (midi) > iSEM (audio) > FX1 (audio) FX2 (audio) > Output (audio)
We want to place Enso in an FX slot where it will do the most good, or at least where we’re willing to remove whatever goes before it. Generally this would be at the end of the chain, but could be elsewhere (for instance if you wanted to continue to mess with the FX in the chain). But lets assume we want to remove everything, leaving only Enso. Our setup should now look like:
Atom > iSEM > FX1 > FX2 > Enso > Output
As soon as we do this, audio will be passing through Enso transparently, provided MONITOR is set to Rec & Stop, which is the default and is just what we want for this exercise. What this means is Enso will pass audio through to the output when it is stopped and while recording but not during playback. This is critical. The reason will become clear soon.
We want Enso to record a fixed number of bars (we’ll use 4), then immediately start playback and mute the audio coming into the app. The settings needed to do this are:
- LENGTH UNIT: Measure (work in units of one measure)
- LENGTH MULTIPLE: 4 (work for four measures)
- MODE QUANTIZE: Measure (start at the beginning of a measure)
- POST RECORD: Play Icon highlighted (start playback after record)
- MONITOR: Rec & Stop
- DUB IN PLACE: Highlighted
There’s one other setting we may need buried in the settings page. For long loops, LONG MEMORY may need to be set to On.
That’s it! The next step is to start the host running, and press the TRIGGER button some time during the last measure before your loop comes around. Enso will now seamlessly:
- Start recording at the next bar and continue for LENGTH MULTIPLE bars
- Simultaneously stop recording, start playback, and mute the incoming audio
You can now mute or remove any apps before Enso in the chain without affecting the audio since it’s coming from Enso now. HOWEVER, if you remove apps, you can’t go back to make changes. So, you probably want to save a “before” snapshot to return to.
It sounds harder than it really is. See the video for walkthrough that may be easier to follow than this detailed guide.