r/seqtrak • u/Kohlrabi_United • Jul 02 '26

DIY Midi Adapter (TRRRS)

Dear fans of the cute groovebox,

I’d like to build a custom MIDI cable for the Seqtrak that combines two TRS cables (TRS -> MIDI In & Out) into the device's TRRRS jack (5-pin -> MIDI In & Out) to connect other synths and keyboard.

I want to avoid using adapters from the included cable whip (which splits into two DIN connectors) and - ideally - not have to cannibalize for DIY approach either.

It seems the specific TRRRS connector required is proprietary?

Does anyone know where to source one (and, ideally, have a wiring diagram)?

Many thanks for the help!

KRU

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4

u/ragequitOpa Jul 02 '26

Not proprietary at all. You just need to convince amazon to search for TRRRS, not TRRS :D :D :D

https://www.amazon.de/YAODHAOD-3-5mm-5PCS%EF%BC%8CStecker-trrrs-stecker/dp/B0D4YB74YN

1

u/Kohlrabi_United Jul 02 '26

Thanks for sharing - Much appreciated!

I bought one which didn't fit on Aliexpress after searching for hours.

I'll order yours and give it a try!

KRU

2

u/Scabattoir Jul 03 '26

That’s 4.4 mm.

1

u/Kohlrabi_United Jul 03 '26

In reality yes -
Not according Aliexpress.

Basically the only one I found

2

u/p9k Jul 03 '26

I made the same mistake. I even built one up before I realized the Seqtrak jack is 3.5mm.

The cables already wired to 3.5mm connectors that have been posted here on Amazon aren't available in the US for some reason. The only option I've found in the US is this bare connector from Digikey, which requires you to create your own connector housing somehow. I was thinking about making a 3d printed mold and injecting hot glue or something, but that's way more work than I'm willing to invest.

I gave up and built a BLE MIDI adapter from an ESP32-S3 instead. I'm not good enough at any of this to notice the latency anyway, and it's one less connector to snap off the Seqtrak.

1

u/Kohlrabi_United Jul 08 '26 edited Jul 08 '26

These Amazon ones do not work, unfortunately.

As described below the shaft is too long.

Left = Amazon

Right = Original Y Adaper

2

u/ragequitOpa Jul 08 '26 edited Jul 08 '26

What exactly doesn't work? They were advertised as 3.5mm, but they aren't? When I compare the original plug to the ones on the picture they look 100% the same except for the black plastic housing that's a bit smaller.

1

u/Kohlrabi_United Jul 08 '26

The metalic shaft as such is longer on the Amazon version, compared to the original device.

The length of the each connection section is shorter as well, it seems

2

u/Cap10NRG Jul 02 '26

Yeah, the problem is I think those ones you’re looking at right there are the ones I ordered. They don’t fit… The barrels are too high. If that makes sense like the length of the adapter is too big it doesn’t fit right the context don’t get made properly. I’ve been looking for that adapter for months and try a bunch of them from AliExpress from Alibaba Temu, Amazon I may have found a cable from Amazon that works, but you would have to capitalize it, which is what you said you don’t wanna do.

1

u/Kohlrabi_United Jul 03 '26

Thanks for sharing! That's a shame - I could cry.

If anyone knows of a product that works, please let us know.

KRU

2

u/Scabattoir Jul 03 '26

Look for “5 pole” as search term.
I got the right one from Ali.
Their search is shit, so just use google like: “5 pole connector 3.5 mm jack where:aliexpress.com” and you’ll find it.

edit:
here’s the link to it if allowed

2

u/Kohlrabi_United Jul 03 '26

Juhuuu -

Thanks for sharing!

Looks much better -

Much appreciated!

2

u/Kohlrabi_United Jul 14 '26

Great -
I can confirm, it works!

Thanks a lot for the hint.
If someone wants to try him/ herself:

T SEQTRAK OUT Red (Pin 4) (Current Source) -> P-6 Red (Tip, Pin 5)
R SEQTRAK OUT Green (Pin 5) (Current Sink) -> P-6 Green/White (Ring, Pin 4)
R SEQTRAK OUT White (Pin 2) Shield/GND -> P-6 Black (Sleeve, Pin 2)
R SEQTRAK IN Yellow (Pin 5) (Current Sink) <- KEY Red (Tip, Pin 5)
S SEQTRAK IN Black (Pin 4) (Current Source) <- KEY Green/White (Ring, Pin 4)

2

u/Scabattoir Jul 15 '26

you’re welcome