– a simplified guide to TRS MIDI

Many MIDI instruments, effects, and Eurorack modules released recently can be connected with small TRS minijack cables. But, the specs they use vary, and are not always documented.
I wanted to consolidate and document what i knew about TRS MIDI as a reference for other musicians.
I organized what data I could find online about these devices from sources like, along with my own research, and built a web UI to search it.

The microsite is online now:

The data is published under a public domain license:

I’m experimenting with ways to support hosting costs while respecting users’ time and privacy:

  • one sponsor per month, with a single, non-obnoxious banner
  • simple, helpful links for any affiliate advertising
  • no tracking cookies (no google analytics)

Hoping some of you find it useful. Feedback welcome!


have you thought about using GitHub pages (which is free) ?

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good question. part of the cost of the site is my time to collect and maintain the data, so i’m looking for ways to cover that. i dont think that can happen with gh pages. i also have a few ideas to extend the site that gh pages wouldnt be able to cover.

but its an experiment, could change in the future.

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Nice one. One suggestion would be to include the direction for the din midi plug diagram i.e. looking at front or looking at the back.

this is a really great resource, and certainly stuff that took a while to dig out whilst pulling together 16n, and labelling it up. Thank you!

I’m not sure I understand why not? GH Pages can support any pile of static HTML/CSS/JS however it’s generated, and thanks to Actions, it’s possible to run static-site-generators-of-your-choice at point of deployment, so you don’t even need to store compiled code in your codebase, just source code. (I’m deploying a variety of production sites using custom actions to build at point of deployment). So… embedding, say, JS for commercials at point of deployment should be fine?

My only other suggestion, in terms of accepting user-submitted data… would be a more user-friendly data format. I get the ontological appeal of triples, but I find them poor in terms of user-experience and they inevitable make for a high barrier-to-entry (or serve as a kind of gatekeeping, in terms of the way RDF is used). JSON has meaningful legs and user-friendliness. But that’s just me.

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good idea :slight_smile:

though, let’s hope over time all manufactures will move to MIDI TRS A … so it’ll only be and issue for ‘legacy devices’.

one extra for your site… ‘AE modular’ currently uses TRS-B.

one problem I had when trying to find din adapters for the organelle-m,
adapters often did not always specify type, rather suitability for devices,
and I also found TRS-A adapters hard to get hold of in the EU.

fortunately… I determined the OP-Z was also TRS-A.
and the T.E OP-Z adapters are well stocked (but never listed as generic TRS-A adapters!)

anyway… if you want a pair of TRS-A, thats the ones Id recommend…

Well, I think my point was that spending money on hosting for a resource that is technically straightforward to deploy feels like a way of earning less for one’s efforts. Instead, spending less/nothing on hosting turns any sponsorship into being entirely about funding labour/ongoing support.

I was unclear as to whether “that’s not possible” was a technical or terms-of-service limitation, and my response was about the former, but not the latter. I was not at any point advocating that anything should be free at point of consumption.

From the current GitHub acceptable use policy

1. GitHub Pages We offer Pages sites primarily as a showcase for personal and organizational projects. Some monetization efforts are permitted on Pages, such as donation buttons and crowdfunding links.

Additionally, GitHub has no problem with running Google Ad Sense say on your own repos.

So it sounds like, if you’re paying for hosting for this site, you could not be in theory, and that wouldn’t be incompatible with attempting to be compensated for the time you’ve spent collecting the information.

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Leeeeet’s wind in talking about hosting for a bit, I think; the whole hosting/GH-pages thing is a bit of a derail, and one I acknowledge I’ve been part of contributing to. @audionerd’s excellent little project is already on a pretty efficient host, and I’m not sure our speculation is hugely on-topic.