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

This comes up too often on the forum to not have one single post that can be pointed to for every “Can I haz OP-1 to MIDI pleez?” post. (Just kidding, this is obviously something not understood very well by the general music-making population)


In order to connect your OP-1 to another MIDI device, you will need a device that acts as a USB Host. This is because USB is not just some electrical signals, but is a data protocol. That means when you hook up your computer mouse to your laptop, the computer acts as a host to say “what are you, and what do you do?” and the mouse says “I’m an input device, and I do mouse things.” If you just try hook your OP-1 up directly to another USB MIDI device via some jankety and creative cabling, both devices will sit there waiting for someone to say “what are you.”

The simplest (and cheapest, since you already own it) USB Host you can use is the laptop you already own. This will handle talking to the OP-1 and routing the signal to any other USB MIDI device you own. If you want to use the OP-1 with another USB MIDI or MIDI DIN device without a laptop, you will need to purchase something like the OPLAB, iConnectMIDI4+, Kenton USB Host, or CerebelUSB MIDI thingy. Each have their own feature sets that may or may not be useful to you, so research what is worth the money to you. Some also connect to iPads and iPhones for app connectivity. If you just want to connect an iPad/iPhone with the OP-1, several OP-1 users have purchased the Apple USB Camera Connector and have had success.

If you would like to be DIY about it, you can fool around with a Raspberry Pi or Arduinos and get the same functionality.

TL;DR - If you want to connect the OP-1 to another USB MIDI or MIDI device, you need a USB Host. There is no way around this.
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That info you posted about iCM original and V1 being two different models with only original(discontinued) working as USB host was very informative too.

sorely needed. somebody sticky this!

Yep - I received my Kenton USB Host today (thanks @ghostly606) and it works like a charm, both for controlling the OP-1 and for using it as a controller.


What I would love to know, though is this: I like to use Xynthesizr on my iPad as a MIDI sequencer and can do this by connecting the iPad with its standard lightning cable, to the USB A port on my Presonus iTwo audio interface. Why can’t I similarly connect it to the USB A port on my Kenton USB Host? Sorry for the slight digression.

Thanks for the helpful topic @GCF.

CB

i think you could connect your iPad to your kenton. in theory it should work. u may or may not need a midi app to route it…?

the easiest iPad solution is the USB lightning connector adapter thing aka the camera connection kit

ipad is my midi hub for usb devices. including the op1. I simultaneously use apps on the ipad to control the midi devices and not just route them.

How do you connect your iPad to your MIDI network @masterofstuff124? Do you know why my iPad works fine as a MIDI controller when plugged into the USB port of my Presonus iTwo but not when plugged into the USB port of my Kenton USB host?


CB

An iPad/iPhone with a midi routing app (midiflow, for example) hooked up to any USB hub with the camera connection kit will handle pretty much any class-compliant USB midi device.

Yep - I received my Kenton USB Host today (thanks @ghostly606) and it works like a charm, both for controlling the OP-1 and for using it as a controller.

What I would love to know, though is this: I like to use Xynthesizr on my iPad as a MIDI sequencer and can do this by connecting the iPad with its standard lightning cable, to the USB A port on my Presonus iTwo audio interface. Why can't I similarly connect it to the USB A port on my Kenton USB Host? Sorry for the slight digression.

Thanks for the helpful topic @GCF.

CB

Can you clarify what you mean by the iPad working “as a midi device?” Do you mean it functions as a midi controller, or just that it works for recording with the iTwo? I ink the issue may come down to the iPad not being a class-compliant usb midi device by itself. Thinki of the OP-1 – it is either only a midi device or only a storage device when hooked up to a laptop. It does not do both at the same time, because these are two different device classes. The iPad is much more robust in that it is like a mini computer. With an app, it can generate midi device data, but won’t just naturally do it unless an app tells it how to do so. If the presonus app is passing both midi and sound info, then there may be some extra processing done by the presonus hardware that lets the iPad do its midi stuff. Just some guesses based on a glance at the iTwo website.

Thanks @GCF. In answer to your question, my aim is to use the iPad as a MIDI controller without having to hook up my computer etc.


Although I’d originally bought the Presonus iTwo thunking I might use the iPad as a recording tool, I’ve never done this and don’t imagine I ever will.

What I have been able to do though is to connect the iPad to the iTwo and use the Xynthesizr app to control MIDI devices (computer-less). In that scenario you additionally provide power to the iTwo via the other USB port (which would normally connect to a computer) and a standard charger plug.

Incidentally, I’ve also been able to get the Xynthesizr app to operate as a MIDI controller via both Wifi and Bluetooth, but obviously this requires my computer.

CB

Ipad-> lightning to usb(CCK)-> usbsplitter or powered HUB-> USB interfaces(cheap usb to din $5; rockband real tone cable; almost all audio interfaces(some have midi); midi keyboards with only USB; arduino’s. and finally my OP1!!!



Is anyone there has the CerebelUSB ?

So to clarify before I buy (this isn’t a rap :)). If I want to run my OP-1, along with a Circuit and say an iPad, if I have one of these units (say the Circuit) as clock master i.e just transpose play over a 4 bar loop, I just need an iconnectmidi? Say a version 2?

Yes, but any USB MIDI interface with a CCK would do the trick. :slight_smile:

With no need to be plugged into a computer?

All you need is a USB host. This can be a standalone box (I.e kenton), an ipad or a computer, etc.


NOTE I am assuming you have your ipad hooked up to the iconnectmidi via a CCK.The iconnectmidi4+ can act as a standalone host, the other types of iconnects not so.

I’m confused. Why does the old black iconnectmidi have no need for a computer to be connect but the newer iconnectmidi2+ does?

My local music store’s webpage is misleading then? (See first video at bottom of page) http://www.dolphinmusic.co.uk/computer-music/midi-equipment/108466-iconnectivity-iconnectmidi2-midi-interface-lightning

Not sure why iConnectMIDI original can do USB Host and iConnectMIDI2 cannot. But either way, you will want the original one or the iConnectMIDI4+. Or one of the other USB Host devices discussed. I would avoid cutting any corners on this price-wise if you plan on having everything work well together.

Hey, can I sync my Korg Emx-1 with Op-1 if I buy a Kenton midi host? I would like to Op-1 act as a slave to my Emx-1.

If you mean this http://www.kentonuk.com/products/items/utilities/usb-host.shtml then I think it should work.


Have others used OP-1 as MIDI Slave with success?