MIDI Connections. 2 computers at once: SSP, MRCC, Ableton. USB how to do so?

Problem: How to connect the SSP & my MacBook Pro to the MRCC via USB for MIDI purposes?

As can be seen in the above photo, there are 4 HOST USB ports and 1 DEVICE USB port.

As we know, our beloved SSP has:

1 high speed USB host port (leftmost port) with USB ethernet adapter support.
1 full speed USB host port (middle port) with USB MIDI keyboard support.
1 USB device port (rightmost port) with USB Audio Class 2.0 support (supports recording into your Mac/PC).

When I play out live, I won’t have Ableton/laptop with me. However, in the studio, I’d like both the SSP and the laptop connected, for MIDI, at the same time.
I do not want Ableton to route MIDI to the SSP in the studio as I want to create master presets for studio and live use wherein I can just leave the laptop at home and head out with the SSP and not be forced into establishing 2 workflows.

I’d like to use the SSP’s USB port 3 (the DEVICE port) for audio I/O to the laptop when in the studio.

Is there a way to connect the SSP and the laptop to the MRCC, via USB only?
I don’t want another USB to DIN device in the chain, if possible.

I only use my MachineDrum (on MRCC port 2 [DIN]) and Ableton as clock masters.
I do use 2 different MIDI controllers with this system but neither generate clock.

According to this Technobear wiki, both the left and middle USB port can be used for networking. I’m not sure if that allows for extra flexibility in solving my quandry.
Putting it in here just in case it is useful.

Any ideas as to how to connect both the SSP and the MacBook Pro to the MRCC via USB only?


Ive got a bad bout of flu at the moment, so can’t really focus enough to give a too precise answer, but till give as good as I can :wink:

first I recently summarised the midi stuff on the wiki, so that might be worth checking

basics are usb midi (actually usb in general) has hosts and devices… computers (like the SSP :wink: ) tend to be hosts, other stuff are devices.

so hosting is done via either USB-A connectors, but as stated in the wiki, the MIDI modules only support ONE device. (however, mine support multiple)

connecting SSP to a computer for midi is a bit of a faff as both are HOSTS.
the usb device port only works for audio on the SSP, theoretically it could support midi as well, but this requires kernel support which I don’t think is included, and certainly not configured.

your options therefore are:
a) use cv over usb
b) use midi din, and get a usb ->din converted (or these days trs-midi)
c) get a usb host to host converter

(c) are pretty rare, and though I have one, I don’t use it often… so I tend to use a or b, depending on what Im up to.

honestly this is not uncommon in these days of instruments built with MCU, I’ve got this host-host issues with a few things, so pretty used to falling back to midi din/trs.
its a pretty common use for my blokas midi hub.

unfortunately, as far as aI know the MRCC doesn’t change any of this, its a bit like the mioXM (which I use), it just acts as a midi hub… so its does not solve the host<->host issue.
its a bit of an oversight, given it wants to be a central hub, you’d have expected it to have multiple host options, rather than just this single ‘PC’ connection.

I just hope one day, we ditch this all, and start using RTP Midi which can be peer to peer, so none of these limitations exists. but support is still very patchy in my experience.
(works well on Macs, but badly on windows, and so-so on linux)

i think if port (2) would be 2 host ports of USB MIDI (and supported by the OS), kents issue could be solved


as I already posted, the 2 usb a ports both work as midi… I actually have tried and used in the past!
did you?

BUT as I also clearly stated they are both HOST ports, so you can only connect a DEVICE to them.
the MRCC has ONE device port, so you could connect it EITHER to your computer OR to the SSP , not both!

so as I said, the solution from a kernel perspective would be supporting midi of the DEVICE port (3), which linux can do… even with audio too… using so called ‘gadgets’. BUT this needs kernel support and then configuration.

so in the meantime, my solutions are the approach that needs to be taken.

what do you think I missed? why do you think my reply was inaccurate?

perhaps you are mixing things up with older versions of the OS, thats why I tried to reiterate the facts in this post… since there are quite alot of ‘inaccurate’ posts on this forum these days.

or perhaps I misunderstood @Kent requirement ?
to me, it basically comes down to wanting to connect both the SSP and a computer to the MRCC.
(for this all, info I gave, afaik is correct)

I very much appreciate both of you having replied and doubly so for Mark’s exhaustive detail.

One of the Conductive Labs / MRCC forum mods replied and, as I suspected, the best option is to get a 2nd MRCC and dedicate that one to live use (which I wanted to do anyhow) and connect it to the other one when back in the studio.
I appreciate you having provided options, Mark. Alas, all of the options seem like kludges that I’d not wish to bring to a live setting.

If I build up my live rig around the 2nd MRCC and plug it into the rest of the MIDI gear when in the studio, it should all work. Fortunately, two MRCCs can be connected via Cat6a and route everything to everywhere.

Again, thanks for thinking about this and I hope that you get over your flu soon, Mark.


Cat6a is the bomb - i see it appearing more & more in (pro) audio gear

Yeah 2x mrcc would likely do the job.
Just be aware that rj45 seems to be used as a proprietary connector/protocol , so there may be some limitations around what can be routed/addressed…. and it might not be much more performant that just using a short midi din cable/usb.

I will say the workarounds i mentioned are all very stable/workable even for live … and much cheaper than a second MRCC - which id personally only do, if I need all the extra ports the 2nd would provide.

I do hope one day, perhaps when midi 2.0 sees wider adoption that rtp midi will become the norm… it’s the logical solution :slight_smile:

Good observations and comments, Mark.

One of the larger goals is to have an easy to ‘grab ‘n’ go’ live rig. I’ll dedicate my live stuff to one MRCC and leave the studio stuff connected to the other. I can connect them to each other and save a preset on each one for when they are together.

Dealing with all of the cabling, every time that I move the system, has been draining of my creative time. I’m very much trying to avoid that.

Here’s what it will look like. I didn’t add every little detail and device but this will get me there at the highest possible expense! :wink: