The Definitive Guide to Trying to Connect Your OP-1 Via USB-MIDI

Thank you for this, I now have it working :slight_smile: so to record the sound, you can only have 12 seconds of recording via drum sampler and 6 seconds as per the normal synth sample recording? It won’t let me record the sounds straight to the tape deck at the moment. I presume this is correct?

Change the input source by hitting mic button

I got it working! Thank you, you guys are awesome! All the best!

Hy all, this is my first post in this nice forum…
just wanted to let you know: I figured out how to program the axoloti-core so it behaves exactly like the kenton usb host.
So hope it is useful to somewone…

clock_and_thru_2_works_perfekt

Hey folks. I’ve been researching the midi timing on the op-1. After a round of testing it looks like the op-1 uses a fixed buffer of 64 samples for midi messages. This means if you use a tempo where 8th/16th/etc. notes divide evenly by 64 samples, you can get razor exact timing from the op-1, but the delay relative to other equipment will be random.

Hy all, this is my first post in this nice forum...
just wanted to let you know: I figured out how to program the axoloti-core so it behaves exactly like the kenton usb host.
So hope it is useful to somewone...

clock_and_thru_2_works_perfekt

Hey @martin, do you have your patch up on the Axoloti community?


No, I havnt. I thought it is very easy. Its really only what you can see in the picture above.
And sorry, I can`t upload it here, .axp files are not allowed here.

just tried the patch but I am something doing wrong. there should be midi notes commin out of the axoloti, if i start the arp on the op1 right?

hey guys! I’m having trouble getting any midi signal through my DIY USBpal usb midi host board. It’s an FTDI Vinculum 2 based device, community effort from the mutable instruments forum: https://forum.mutable-instruments.net/t/diy-usb-host-midi-din-converter-usbpal-released


It works with other midi controllers, except for the OP-1. the firmware is opensource, I built it and flashed it my self. I can’t really write code, but I can edit the source and reflash if you guys have some suggestions. it’s a really cool little thing, but the whole point of building it was to connect my OP-1:) hope someone here will have an idea what’s going on :slight_smile:

Thanks!

Are there specific channel settings you have to use? Or does it just pass through everything? I didn’t read through that entire forum post, but potentially an issue could be whether the OP-1 is set to USB MIDI before it is plugged in or not. Maybe try setting it to MIDI before plugging it in.

hi guys, anything new on hobbytronics? is it working now?

Has anybody had success syncing a Novation Circuit with OP1? I’ve tried doing it within the computer, within Ableton, using my Axoloti as a host (in various configurations), and I just CANNOT get them to sync. I can MIDI notes flowing each way, but start/stop and tempo sync do not work in any way shape or form. I’ve just had the most frustrating last few hours trying to get it to work with no avail.


FWIW both of them sync perfectly with Ableton as the master, but they just will not speak to other and it’s driving me nuts :,-(

I wonder if you can wire mini-usb jack to midi cable the same way it is done in those cheap midi-usb cables and if it would work with OP-1

I wonder if you can wire mini-usb jack to midi cable the same way it is done in those cheap midi-usb cables and if it would work with OP-1

You need a USB host such as iOS device, computer or special device like the Kenton box. I use a raspberry pi specifically for this which generally works pretty well.

I wonder if you can wire mini-usb jack to midi cable the same way it is done in those cheap midi-usb cables and if it would work with OP-1

You need a USB host such as iOS device, computer or special device like the Kenton box. I use a raspberry pi specifically for this which generally works pretty well.

But you dont need host to send midi from one device to another if we take a midi-keyboard as example and some synth with midi-in. Or host requirement is a flaw of op1/usb-midi in general?

Excuse my layman terminology but a USB cable doesn’t carry raw MIDI data as is that can be accepted by a MIDI DIN equipped device. It needs the host to translate it.

MIDI and USB are very different in design. MIDI is basically a 1 to 1 protocol. USB is a bus protocol, which means you need to play nice with everyone else on the cable. With MIDI you just starting sending data out on the cable – on USB you have to wait your turn to send out data. That being said, a small cable could be designed that is like those cheap MIDI USB cables. It just wouldn’t be as cheap and would need to be either battery powered or plugged into a separate power source.

Hi Guys, I´m new here and into the OP-1

Does anybody knows a good app for Android to serve as USB-MIDI Bridge between mi full size keyboard (midi controller) and the OP-1 using the OTG-USB cable (CCK equivalent) + USB HUB?

Thanks in advance.

Thanks to all for the comments Ive just bought a MIO4 can’t wait for it to get here

Tl;Dr - I’ve read this thread multiple times and done a lot of research and still have a ton of questions. I’m telling my story and explaining my setup, and hoping for thoughts and feedback from the forum.



FWIW, I have no experience with MIDI yet. I did post and search the Digitakt forum. Someone there linked back to this thread. Since it appears that the real challenge is with the OP-1 (other devices don’t seem to have the same problems with MIDI connections between devices), I’m hoping that this is the best place to seek advice.

I have an OP-1 and a Digitakt and plan on adding an 0-Coast (or other similar device) soon. I don’t have an audio interface. I want a simple, headless setup that doesn’t require connection to my laptop. I generally prefer to work on my lap in the living room, and don’t want to be tied to a desk, etc. Ideally, I’d like to only connect to my laptop for recording out to Ableton when I’ve finished a track.

I want to be able to connect all my devices and control the others (probably from the) Digitakt. I also want a simple way to pass audio through that will allow me to hear everything, from all devices, real-time as I play, and that will allow me to send all audio out to Ableton for recording when I’m ready.

Currently, I have aux cable from OP-1 out to Digitakt in, but the input source on Digitakt doesn’t allow setting the volume of the input. This either means that I have to turn down all other Digitakt audio (which is not simple in the Digitakt, as every track has multiple audio levels) or turn up the OP-1, which at max, is only just about good enough. I don’t think it would be sufficient for recording.

Without MIDI control, playing each is possible, but not exactly what I had imagined when purchasing the Digitakt.

I know that I need a UBS-MIDI host, but I want the option of sending MIDI in either direction, which the <span style=“color: rgb(37, 38, 30); font-family: “lucida grande”, “Lucida Sans Unicode”, tahoma, sans-serif; background-color: rgb(252, 252, 255);”>CerebelUSB MIDI doesn’t allow. I also want MIDI-MIDI, as I expect that connecting Digitakt to anything like 0-Coast would require that.

I’m currently considering the following:

<span style=“color: rgb(37, 38, 30); font-family: “lucida grande”, “Lucida Sans Unicode”, tahoma, sans-serif; background-color: rgb(252, 252, 255);”>iConnectMIDI4+ and iConnectMio4 and Pisound

I haven’t seen others discussing the Pisound here, and don’t know if it would work, or what limitations exist.

I don’t fully understand the difference between the iConnectMIDI4+ and the Mio4 yet, [edit: looks like the MIDI4+ has some definite advantages like USB audio pass-through]. Maybe someone here can sum that up. I’m pretty sure that I don’t want the Kenton host as it generally get’s pretty iffy reviews, and is also expensive. I’d rather just spend a little more for one of the iConnect models since they have more ins and outs. OPLAB isn’t available anymore, except used on Ebay, so I haven’t really considered that. It’s also crazy expensive.

It would be great to have a quick link section in the header post with a table of known issues, workarounds, common configurations, and supported devices. The Hobbytronics device appears to be a bust as they now list OP-1 as definitely not supported. Diagrams, photos, videos of success stories would also be tremendously helpful and really enhance this as the definitive guide.

Thoughts, advice, anything would be greatly appreciated.
Cheers and Merry Christmas