MIDI over TRS

[ElmerJFudd]

' The MIDI Manufacturers Association (MMA) has released a Specification for use of TRS Connectors with MIDI Devices. It is available for free download by MIDI Association members.

 

The document defines how to wire "TRS" (tip-ring-sleeve) connectors for use with MIDI devices, and describes the necessary device circuitry and cable specifications to support MIDI communication over the TRS connection.

 

The inclination towards smaller hardware devices has made it increasingly difficult to make use of DIN connectors for MIDI In/Out in the past few years. Many manufacturers have chosen to use 2.5mm or 3.5mm "TRS" connectors instead. But since there was no specification for wiring a TRS MIDI connection, the situation exists where two devices may not have chosen the same wiring scheme, so compatibility between devices is not known. By specifying the pin-out for the TRS connection, and also the connectors for the adapter cable, we can ensure greater interoperability between TRS and DIN-MIDI devices.'

 

https://www.midi.org/downloads?task=callelement&format=raw&item_id=171&element=f85c494b-2b32-4109-b8c1-083cca2b7db6&method=download

[The Real MC]

I reject this convention. 3.5/2.5mm TRS do not have a long life and are unreliable for digital I/O. Fine for consumer audio but not digital I/O.

[ElmerJFudd]

I reject this convention. 3.5/2.5mm TRS do not have a long life and are unreliable for digital I/O. Fine for consumer audio but not digital I/O.

 

Thoughts on MIDI over dedicated ethernet live?

 

https://www.iconnectivity.com/blog/2018/3/7/ethernet-midi-for-live-musicians-an-iconnectivity-guide

[OB Dave]

Thanks, I hate it.

 

I fully understand the need for an easily-sourced, low-profile connector, but TRS connectors - especially 2.5mm - are the spawn of Satan. This is an enormous failing on the part of the MMA and all around a generally terrible idea.

 

Or would you like to know how I really feel?

[mcgoo]

Or would you like to know how I really feel?

 

Yes, please. Don't hold back! Lol

 

This strikes me as even less useful than MIDI over USB, which I'm not a huge fan of for live use. I've had a few controllers with USB plugs go bad after a few hundred setups and tear downs, whereas the DIN plugs never have this problem. 1/8" TRS just seems like a bad idea.

[Docbop]

I was thinking that's cool at first thinking at was 1/4" connectors which are sturdy and their is lots of cable option depending on how shielding you want for DIY and lots of options for premade cables. Then see its the 1/8" and say no way. Someone mentioned using RJ-45 connectors (network) that could be very interesting idea if they could come up with a standard wiring. There are enough connections you could have two runs in a single connector like in and out in one cable. For DIY types as long as your eyes are good you can get a stripping and crimping tool to make your own cables and lots cable option depending on how much shielding you want. So making custom length cables wouldn't be that hard or repairing cables that go bad.

[Jonathan Hughes]

"1/8" TRS just seems like a bad idea."

 

Yet, there are companies who have have been using these connectors in their products for years, due to lack of space for a MIDI DIN connector.

 

 

 

"This is an enormous failing on the part of the MMA and all around a generally terrible idea."

 

You're barking up the wrong tree. The MMA has just created a specification/standard for the companies who are already using this connector so that going forward, everyone does things the same way, and users don't need to worry about two different devices with the same connector being wired differently. This couldn't be any clearer from the quote in the original post, specifically the part that says "By specifying the pin-out for the TRS connection, and also the connectors for the adapter cable, we can ensure greater interoperability between TRS and DIN-MIDI devices". If you're afraid of 1/8" TRS connectors replacing DIN connectors (which is very unlikely on anything that has room for it, complain to the manufacturers.

[miden]

I've used the trs MIDI cable (IK Multimedia gear) and it always seemed very easy for it to get knocked slightly or pulled so connections are lost. When using it live I used to tape it up

 

The Cat -5 cable and connector idea has been around for a while, but the issue with them is the small plastic locking clip (and the connecting thin strip of flexible plastic that connects it to the body of the connector) wears out and becomes very fragile. Or indeed even when new, if one accidentally "over-extends it" by bending it backwards (easy to do when inattention strikes ) then it becomes looser than a TRS connector. I would have thought MINI-Dins might have got a run? Roland was using a proprietary one years back for some gear, not sure what happened to that.

 

Bottom line? There are far better attachment options than mini jacks, cat-5 and even USB....perhaps there is some other underlying reason (political? economic? lobby groups?) that has resulted in opting for the TRS.

[OB Dave]

companies who are already using this connector so that going forward, everyone does things the same way

I mean, that is one way of looking at it. Another way of looking at it is: if it becomes standardized, it becomes the standard. And I don't want to see the use of these things proliferate.

[Reezekeys]

I reject this convention. 3.5/2.5mm TRS do not have a long life and are unreliable for digital I/O. Fine for consumer audio but not digital I/O.

 

Thoughts on MIDI over dedicated ethernet live?

 

https://www.iconnectivity.com/blog/2018/3/7/ethernet-midi-for-live-musicians-an-iconnectivity-guide

If the reason for using midi over ethernet is only to find a connection jack/plug with a smaller footprint (the goal of this new 2.5/3.5mm "standard"), I don't get that. True, an ethernet jack is slightly smaller than a 5-pin DIN jack, but I'm guessing it needs additional electronics to implement, at both ends of the connection. How much room are you saving and how much more is the cost to do that? Not to mention that buying an external midi device that uses ethernet would require you to have a compatible interface at the other end. IMO ethernet midi is best used for what your link describes - multiple channels of midi on a large stage requiring long cable runs. For this regular schmoe with a controller keyboard going to a laptop, a 35-foot long 5-pin midi cable is what I carry and it works just fine. I chronicled in a years-old thread here how the light bulb turned on for me after my experience on a large stage where adding a USB extension cable caused stuck notes. Now it's 5-pin midi for bigger shows, while I still use USB for local gigs where I know the laptop is gonna be close. BTW I agree with RealMC, I would not trust these miniplugs & jacks.

[Mike Warren]

1/8" TRS connectors are available with screw-down rings. As long as a quality socket and a screw-down ring is used they will be as, if not more reliable than 5pin DIN.

 

These connectors are used professionally in wireless mic transmitters.

[ElmerJFudd]

I reject this convention. 3.5/2.5mm TRS do not have a long life and are unreliable for digital I/O. Fine for consumer audio but not digital I/O.

 

Thoughts on MIDI over dedicated ethernet live?

 

https://www.iconnectivity.com/blog/2018/3/7/ethernet-midi-for-live-musicians-an-iconnectivity-guide

If the reason for using midi over ethernet is only to find a connection jack/plug with a smaller footprint (the goal of this new 2.5/3.5mm "standard"), I don't get that. True, an ethernet jack is slightly smaller than a 5-pin DIN jack, but I'm guessing it needs additional electronics to implement, at both ends of the connection. How much room are you saving and how much more is the cost to do that? Not to mention that buying an external midi device that uses ethernet would require you to have a compatible interface at the other end. IMO ethernet midi is best used for what your link describes - multiple channels of midi on a large stage requiring long cable runs. For this regular schmoe with a controller keyboard going to a laptop, a 35-foot long 5-pin midi cable is what I carry and it works just fine. I chronicled in a years-old thread here how the light bulb turned on for me after my experience on a large stage where adding a USB extension cable caused stuck notes. Now it's 5-pin midi for bigger shows, while I still use USB for local gigs where I know the laptop is gonna be close. BTW I agree with RealMC, I would not trust these miniplugs & jacks.

 

It"s for long cable runs in live situation. Where the players are sending MIDI to one computer running all the sound engines located FOH.

[GovernorSilver]

My Empress Zoia is the only device I have that requires MIDI TRS adapters. Seems ok so far.

[The Real MC]

Thoughts on MIDI over dedicated ethernet live?

 

https://www.iconnectivity.com/blog/2018/3/7/ethernet-midi-for-live-musicians-an-iconnectivity-guide

 

The idea of long distance transfer over the long established TCP/IP is a good one. Translators won't be that expensive, any computer with an Enet jack should be able to route to your DAW via a driver, and industry standard switchers and routers are widely available.

 

While the usual Ethernet cable isn't road-worthy with their RJ45 jacks, Neutrik makes a more rugged interconnect that is basically the RJ45 inside an XKR jack. I use them on my Vox Valvetronix footpedal unit.

[Anderton]

companies who are already using this connector so that going forward, everyone does things the same way

I mean, that is one way of looking at it. Another way of looking at it is: if it becomes standardized, it becomes the standard. And I don't want to see the use of these things proliferate.

 

This has been around for a while...I covered MIDI-over-TRS over two years ago, with diagrams for the wiring, on craiganderton.org. Note that the same specification applies to 1/4" connectors.

 

The problem is not "if it becomes standardized," the problem is that companies were already doing it, and it wasn't standardized. A paramount principle of MIDI is that stuff has to work together. This is even the case with MIDI 2.0 gear being able to communicate with MIDI 1.0 gear. Although you may think "this is an enormous failing on the part of the MMA," whether manufacturers want to use TRS, and whether consumers want to buy that gear, is up to them. It is up to The MIDI Association (formerly known as the MMA) to make sure that gear can talk to each other. It would have a been real dereliction of duty if the MMA hadn't stepped in to make sure that MIDI gear from different manufacturers was compatible.

 

To keep up-to-date on the latest MIDI info, I recommend visiting midi.org. Most of the MIDI 2.0 specs are posted at this point, as well as other info. Disclaimer: I am currently President of the MIDI Association, and will hold that position until January 2022.

[Anderton]

Thoughts on MIDI over dedicated ethernet live?

 

https://www.iconnectivity.com/blog/2018/3/7/ethernet-midi-for-live-musicians-an-iconnectivity-guide

 

The idea of long distance transfer over the long established TCP/IP is a good one. Translators won't be that expensive, any computer with an Enet jack should be able to route to your DAW via a driver, and industry standard switchers and routers are widely available.

 

While the usual Ethernet cable isn't road-worthy with their RJ45 jacks, Neutrik makes a more rugged interconnect that is basically the RJ45 inside an XKR jack. I use them on my Vox Valvetronix footpedal unit.

 

Yup! One of the main activities of the MIDI Association is to make sure that MIDI works over any transport. With MIDI 1.0, you didn't have a choice - it was a hardware serial port. The next step was USB, but ideally, MIDI will work over protocols like AVB, Dante, etc. The BohmBox has already moved in this direction, and it works very well.

[Tom Williams]

If you're afraid of 1/8" TRS connectors replacing DIN connectors (which is very unlikely on anything that has room for it), complain to the manufacturers.

I wish I concurred with the emphasized text, but as soon as they see that they can save $0.75 on the manufacturing process, a lot of guys we like(d) will be making the change.

[Anderton]

Are you sure about that figure? I would assume it costs the same to wave solder a PC-mount jack, whether it's DIN or TRS. The cost of the jacks themselves isn't too far apart. Also if a company is using DIN jacks and has 5,000 sitting around, they might not want to have to more inventory of something else. I suspect the TRS 1/8" jacks will be used mostly with small, inexpensive gear, but we'll see how it shakes out. I think more gear is choosing to go the USB route anyway.

[elif]

I'd prefer to see Mini-XLR connectors instead of small TRS. Though made by Switchcraft, Neutrik and maybe others, I haven't seen PC mount yet.

[Mike Warren]

I'd prefer to see Mini-XLR connectors instead of small TRS. Though made by Switchcraft, Neutrik and maybe others, I haven't seen PC mount yet.

 

They are available: Link

 

I'd like that too, but they are significantly more expensive than 3.5mm and DIN.

[Throbert]

I'd prefer to see Mini-XLR connectors instead of small TRS. Though made by Switchcraft, Neutrik and maybe others, I haven't seen PC mount yet.

 

They are available: Link

 

I'd like that too, but they are significantly more expensive than 3.5mm and DIN.

I'd welcome a change to XLR aswell, the thought of being able to lock connectors in seems real appealing to me would be nice to do that with USB too.

[ElmerJFudd]

If all you need is the 3 points and to follow the standard set on TRS, then it"s easily possible. But, it"s not going to give manufacturers a tiny jack to include on slim hardware. Even RJ45 isn"t much smaller than 5 pin DIN.

[confidence]

It"s for long cable runs in live situation. Where the players are sending MIDI to one computer running all the sound engines located FOH.

 

Wouldn't the logical thing then be standard MIDI cables and plugs from the players to a multi-port MIDI interface or merge unit located FOH, and then USB or whatever's easiest from that to the computer - where it's safely tucked away with only a short cable needed, won't get knocked etc.

[Reezekeys]

If all you need is the 3 points and to follow the standard set on TRS, then it"s easily possible. But, it"s not going to give manufacturers a tiny jack to include on slim hardware. Even RJ45 isn"t much smaller than 5 pin DIN.

How about these - "mini" xlr:

 

[Reezekeys]

It"s for long cable runs in live situation. Where the players are sending MIDI to one computer running all the sound engines located FOH.

 

Wouldn't the logical thing then be standard MIDI cables and plugs from the players to a multi-port MIDI interface or merge unit located FOH, and then USB or whatever's easiest from that to the computer - where it's safely tucked away with only a short cable needed, won't get knocked etc.

5-pin DIN midi cables can certainly run farther than USB cables, but some FOH positions are quite far from the stage. Also, if you had multiple keyboards or other midi sources you might be talking about a lot of individual cables. Better to go e-net for this kind of thing imo, since you can multiplex several midi streams into one cable.

[ElmerJFudd]

It"s for long cable runs in live situation. Where the players are sending MIDI to one computer running all the sound engines located FOH.

 

Wouldn't the logical thing then be standard MIDI cables and plugs from the players to a multi-port MIDI interface or merge unit located FOH, and then USB or whatever's easiest from that to the computer - where it's safely tucked away with only a short cable needed, won't get knocked etc.

 

 

Apparently the way it"s been implemented by manufacturers is translator box - USB or 5 pin MIDI in and Ethernet cable out to Mac/PC wherever it"s located. Check out the Bohm box or iConnectivity MIDI products linked earlier in the thread.

 

I don"t see a reason why this wouldn"t work very well for MIDI at long distances since they have been using it for audio for a long time now on PA system installs and it"s working great. - horrible sentence, I know.