[ibigb]

> MIDI doesn't support per-note pitch bend

"MIDI Polyphonic Expression" and is a new MIDI standard created by us, ROLI, Apple, Moog, Haken Audio, Bitwig and others for communicating over MIDI between MPE controllers ... The principal reason for MPE is to get around a limitation of MIDI: Pitch Bend and Control Change messages must apply to all notes on the channel. This prevents polyphonic pitch bends and polyphonic Y-axis control (which uses Control Change messages) over a single MIDI channel. MPE solves this problem by sending each note's messages on a separate MIDI channel, rotating through a defined block of channels. Here's a brief summary of MPE: http://www.rogerlinndesign.com/mpe.html

Today there seem to be work arounds, not that a new midi version would not work better, however.

[spamizbad]

MPE is a bit of a mess. First, it requires a dedicated MIDI “port” per device, and two, you have latency issues since you’re sending a lot of control data over 31KBAUD.

Then there’s the fact that many manufactures promise MPE support in their devices, but rarely in 1.0 firmwares... you either ship with it or wait 6 months for either a crummy implementation or a statement from the manufacturer walking back support. It sounds like a non-trivial software implementation task, especially on devices with resource starved I/O processors

[enqk]

I think if you're doing MPE, you can afford USB-MIDI

[spamizbad]

I could be wrong, but USB MIDI is still limited by the same bandwidth and latency constraints. I don't think it's any faster in terms of baud rate, despite being carried over a faster bus.

[enqk]

USB MIDI isn't limited by the constraints, because they're only about the legacy physical link

[TheRealPomax]

Pretty sure I don't want cumbersome and amazingly terrible MIDI cables anymore in 2019. Give me an updated MIDI protocol, and then talk/listen to my device over USB. There is no reason to use incredibly bad MIDI cables for this. And before we all go "but USB cables are more fragile", don't use a standard consumer or studio cable during a live performance, and done. Let these dumb MIDI ports die with MIDI 2, they are not of this time.

[djaychela]

I'd have to disagree with this. I've done lots of stupidly over-complex live music production, and MIDI has been rock solid and reliable whenever I've done any of it. The cables are physically robust, and the protocol works well. It's an incredibly well-designed system. MIDI ports are not dumb - in fact I'd venture that they are one of the reasons that MIDI has become so popular - they're simple and universal, and cables and connectors are easily made yourself - not something that's the case for USB, particularly USB-C - can't imagine trying to solder anything like that together!

Back in the day I made loads of custom switch boxes and so on to allow whatever bizarre system I thought was a good idea into a reality - in fact I only got the last one out of my studio about 3 weeks ago when I finally removed the 19" rack I've had in there for the last 20+ years. The ubiquity and compatibility of MIDI has been one of the reasons that it's still around today. Forgetting that would be a huge mistake, IMO.

[timc3]

Couldn’t agree more.

[detaro]

USB with it's max 5 m cable length unless you use special repeaters etc wouldn't be a good choice IMHO.

If you wanted to switch to something common, I'd personally say Ethernet (or something "normal", and a specified transport over Ethernet). Handles the distances and data rates more than fine, parts to implement it are widely available, it's already used more and more in stage and recording setups, so specialized components are available too. In the audio sector, standards to distribute precise clocks are around, one could maybe reuse those to get it past P2P connections (although that kind of gear is still kind of expensive right now). Still quite a step up in complexity though...

[ATsch]

There's already a lot of professional sound gear that uses Ethernet with a custom layer 3 (iirc) protocol for digital audio, so supporting Ethernet would sure make sense.

[jdietrich]

Your comment doesn't make any sense to me. The 5-pin DIN plug was specifically chosen for MIDI because it's a rugged, reliable connector suitable for use in professional environments. If you think that MIDI 2.0 should only use USB and that USB cables aren't suitable for use on stage, then you're saying that nobody should use MIDI on stage. That strikes me as profoundly silly.

MIDI is the lingua franca of music equipment. It controls mixing consoles and effects units, it synchronises music to lighting, it provides timecode and controls recorders. You might not use that stuff, but it's an essential part of the spec that is used every day by professional musicians and engineers.

[icebraining]

that USB cables aren't suitable for use on stage

I think they're saying one should use rugged USB cables for live performance, rather than a typical consumer-grade cable.

[TheRealPomax]

I do not think MIDI should only use USB, but I absolutely want the option to stop using MIDI cables. As for ruggedness, that's a reversed argument. If MIDI over USB-C is a thing, and the industry embraces it, you get rugged enough cables and connectors to work on stage and on the set. There is, right now, without MIDI2 even being done, literally no reason for anyone to make rugged USB-C cables. So saying "there are no rugged USB cables, MIDI has proven itself" is a matter of course.

If MIDI2 can work with USB-C in a way that devices can be linked, instantly, because the USB-C circuitry they use can speak just enough USB to verify the connection is between two MIDI devices, then I will be more than happy to give my MIDI cables away and never bother with them again.

And yeah of course a stage or studio setup will still need them for the foreseeable future, it's not like decades of midi instruments vanish overnight. But you'll also start seeing USB cables thrown into the mix, and eventually you might not see MIDI cables at all in 20, 30 years.

It has to start somewhere.

[SeanLuke]

USB has a huge problem compared to MIDI cables: it's not optoisolated. That alone almost takes it out if the running for controlling synths via laptops.

[dfox]

To be fair the approach taken by MIDI for optoisolation (and getting essentially differential interface for free with that) is in fact one big ugly hack.

[danellis]

Why is it a problem that it's not optoisolated? Audio hardware (including synths, laptops, keyboards, DAWs etc) are connected via USB all the time.

[SeanLuke]

Connecting a controller keyboard to a laptop isn't an issue because it shares power and ground with the laptop. But synths on separate power are another issue entirely. For example, the Waldorf Blofeld has a USB MIDI connection; I attach mine to my Macbook Pro and its audio presents a ground hum and an electric buzz whose pattern matches the Macbook's processor utilization. Attach via 5-pin DIN MIDI and the problem is gone.

USB wasn't designed for this use case, and it is a very, very common problem.

[TheRealPomax]

Except sometimes it is: I have an audio workstation with two "yellow" USB ports (as opposed to standard USB2's black and USB3's blue) that are dedicated audio USB ports with additional circuitry specifically for connections to audio devices. My Komplete Audio 6 kept buzzing and letting me hear my cpu activity in my old system (is it both amazing and the most annoying thing ever to hear your mouse move as HF signals), and has had perfect audio since switching to those for-audio USB ports on the new motherboard. As far as I know only Gigabyte makes these (my specific board is a z170x gaming 5) but they exist, and they're great.

Certainly, UBS in general can't be used for this purpose, but if there's true industry buy-in for MIDI over USB then it's not hard to imagine more and more USB hardware will get made that can compensate for that problem. For instance, I wouldn't imagine laptops to get isolated USB, but a shiny new post-MIDI-2 audio interface sure would.

[jdietrich]

Ground loops. Stages are very electromagnetically noisy, mainly because of lighting dimmers. If you connect a mains-powered computer to a mains-powered master keyboard via a USB cable, you've just created a big antenna for all of that RF noise. That noise will travel through the ground plane into your USB audio interface.

In that environment, isolation is a constant concern. Connections that are inherently isolated make fault-finding far more straightforward and obviate the need for external isolation boxes.

[danellis]

Must be a solved problem, since USB is ubiquitous.

[elihu]

There are still many reasons to prefer MIDI cables over USB. The main one is that you can plug pretty much any MIDI device into any other and expect it to just work. With USB, you almost always at least need a computer or MIDI host device to act as an intermediary. MIDI cables can also be a lot longer than USB and (if the receiving device implements the spec properly) the devices are optically isolated.

There are a lot of potential technologies that could improve upon the antiquated MIDI cable standard, but USB is actually worse in a lot of ways.

CAN bus might be a good option; it's fast enough, and is already available on a lot of cheap microcontrollers. I haven't worked with it, though; maybe there's a shortcoming I'm not aware of.