Ok, I’ve done some testing on the M1 Macbook Air, and these are the results.
Settings and conditions for all tests, unless noted otherwise:
- Good headphones directly into the headphone out of the computer.
- Audio module connected to standard, internal audio interface.
- 44.1 Khz, blocksize 1024.
- 1 engine thread used
- Native (Retina) screen resolution with 60FPS
- Rack window zoomed to whole screen
- Screen is on the whole time, powercable is connected.
- Used CPU is given for the whole machine as such.
- Temperature readings are given as two readings: 1) By touching the hottest strip of the cabinet, just above the function key row. 2) By touching the cabinet next to the trackpad.
- When nothing is remarked it means everything works, plays and sounds as it should, with no audio stuttering at all.
- Each patch is run for 15 minutes straight or more. Any thermal throttling will happen before this.
- It’s the normal VCV Rack for Mac downloaded and installed, which means an x86/Intel binary running under Rosetta2 on the M1 Mac.
- Unless otherwise noted, scrolling the Rack is buttery smooth, with no lagging whatsoever. Very graphically satisfying.
- Also, just as a reminder, the M1 Macbook Air has no fan and so makes no sound at all!
- This M1 Macbook Air is the base model: 8GB RAM and 256GB SSD. In other words: The smallest M1 machine that Apple makes
- All test patches are fully wired up and playing actual “music”. This to maximize the chance of getting actual, real-use results.
Before Rack is opened:
- Used CPU: 2%
Test 1:
- Rack default patch
- Used CPU: 11%
- Temperature: Skin temperature / Cold
Test 2: test-02.vcv (8.1 KB)
- The Test-1 patch with Midi module replaced with Bogaudio llfo, addr-seq and VCV Qnt:
- Used CPU: 11%
- Temperature: Slightly above skin temperature / Slightly below skin temperature
Test 3: test-03.vcv (20.4 KB)
- The Test-2 patch built out with another row of Plaits, Clouds, 2xRings plus Plateau reverb etc. So a modest and quite musically relevant 2-row patch with 4 voices.
- Used CPU: 12%
- Temperature: Slightly warm / Skin temperature
Test 4: test-04.vcv (76.7 KB)
- The Test-3 patch built out with big mixer+expander, GUI effects, and 3 instances of Dexter. A healthy 6-row patch with 7 voices.
- Used CPU: 15%. Rack is using about 75% of one core.
- Temperature: Slightly warm / Skin temperature
Test 5: test-05.vcv (152.9 KB)
- 3 voices of Dexter with 4 x Dexter in each voice, so 12 Dexters all in all, plus various mixers, reverb, etc. I’ve chosen Dexter for testing because it uses significant CPU.
- Used CPU: 20%
- Temperature: Warm / Slightly above skin temperature
- At this point I had been running Rack with this patch for a couple of hours. I felt out the underside of the cabinet and the side towards the screen is quite warm. Seems like it’s the main heat disipation point of the cabinet. So when you do something CPU intensive on this laptop for a long time you should not be having it on your lap, and it should definately be sitting on a level, hard surface with some airflow underneath.
Test 6: test-06.vcv (284.9 KB)
- The test-5 patch doubled up, so now 24 instances of Dexter in all. So that’s a 7-row patch of which 6 are overflowing with Dexters.
- When I added the 5th voice the audio finally started breaking up using 1 engine thread. I bumped it up to 2 threads and everything was fine. After 2 minutes with the full patch it started to break up a little again, and I bumped it up to 3 threads after which it was steady.
- Scrolling the patch is still completely fluid at this load. Good GPU on that chip.
- Used CPU: 40%. Rack is using about 280% of one core.
- Temperature: Hot / A bit above skin temperature. Both the strip above and the underside of the cabinet are hot, but not hotter than you can still touch it continuously without burning yourself or being uncomfortable. The machine is thermally stable also after playing this patch for half an hour.
- I consider this patch to be very close to the practical limit of this machine. You might get away with adding another row of Dexters (so 4 more) to it, but it will likely get quite hot and another background process starting up and your audio will instantly break up I think.
My conclusion is that this little machine is very capable at running Rack and has a shocking amount of power, runs very cool unless you really push it, with very capable graphics. I feel like with Test-6 I reached the practical limit and don’t plan on doing any further testing. Using more CPU efficient modules than Dexter, I reckon that I could run a 8-10 row patch on this machine. Whether that’s sufficient for you is for you to decide.
I wouldn’t run a PRO studio on this machine alone, but for home use running moderately beefy but non-extreme patches I think it does the job well. It’s been a very pleasant surprise and it’s a fantastic “little” laptop.