I have experienced latency in various weird ways and for weird reasons.
- Different USB cables can have different latencies. I did not want to believe it either.
- Some keyboards (probably older ones) have more latency with USB than 5-pin DIN. That was certainly the annoying case with my Casio PX-5S.
While the one-the-wire specs of USB show massively better bit rates than lowly old MIDI, sometimes the internal handling of USB bus signals on different devices is … non-musical, to put it lightly.
For years I had a setup like this:
- Casio PX-5S - MIDI Out (5-Pin) ==>
- MIDI In (5-Pin) - Arturia KeyLab mkII - USB-B to USB-C ==>
- USB-C - MacBook Pro
I tried all kinds of combinations of cord types (USB-B to USB-A, USB-B to USB-C), cord brands (ULine, etc.), into various kinds of USB hub dongles that supported USB 2.0, 3.0, 3.1, USB-C, Thunderbolt, etc.
I eventually discovered that the closest I could get my Casio PX-5S to feeling right was to use my old MIDI cables (literally old, from 1986) and pass that MIDI through my other keyboard controller. It made no sense, but it worked.
I say all that to let you know that it’s a good idea to experiment, even when you think something shouldn’t work. MIDI 5-Pin should be much slower and latent. USB cords should be fungible. I’ve learned to question all assumptions when it comes to this stuff.
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