Request: 1/4" MIDI control of Source Audio C4

In a recent firmware update, Disaster Area MIDI controllers were given the ability to control the Source Audio C4/Spectrum via the DMC’s 1/4" jack into the C4/Spectrum’s 1/8" control port connection (the connection designed for connection to a Neuro Hub or expression pedal). It sounds like Disaster Area more or less came across this possibility by chance (supposedly it shouldn’t be possible, but verified by SA and many users to work flawlessly). I would love to see this option implemented in the Morningstar controllers if there is a way to figure it out, as I have now moved on completely to an MC6 for my controller needs and would love to ditch my Source Audio Neuro Hub and also am not a fan of USB connections.

1 Like

But…. Unless I’m missing something, the DMCs do Host, the MC doesn’t. So I’m guessing not possible?

I’d like that! Maybe it will work, since we wouldn’t use the usb port?

The current update of the DMC that I am talking about allows not interfacing with the USB on either the C4 or the DMC controller, it is using the 1/4" omniport of the DMC into the 1/8" control port of the C4 (what would normally be attached to either a Neuro Hub or an expression pedal) and the C4 is able to receive CC messages that way (of course the DMCs also work with the C4 via USB Host connection which is how I used my DMC-8 with my C4 before upgrading to a Morningstar controller, and I found spotty due to tight spaces and unreliable USB connections). I’m not sure is this is somehow related to the “Host” functionality, but I don’t believe so. I personally found using USB connections on a pedalboard pretty unreliable, and so am less interested in going back to that for controlling the C4- but using 1/4" MIDI as the DMCs are able to do with the C4 would be ideal!

1 Like

We don’t have the C4, but is the jack TRS or TRRS? If it’s TRS, I’d assume its no different from any other TRS MIDI implementation, so you can test out the different MIDI Out settings and see which works.

It’s TRRS on all such Source Audio pedals. So @Sunbeast I guess a 1/4” TRS to 1/8” TRRS cable, wired correctly, connected to an omniport with the required midi type set would be worth a go.

As to how that cable would be wired, who knows? Maybe a standard cable with a TRS 1/8” end like this would be worth a low cost experiment?…

Further reading of e.g. source audio hub manual shows that they’re handling x and y axis data for the hot hand on these 1/8” ‘control input’ jacks. So my guess would be the second ring is only used for hot hand control. Maybe a normal cable would work somehow in such case?

Input 2 can also be used to pass down data from the neuro hub with a trs cable. I’m going to do some tests this weekend. I have an adapter that splits a trrs plug to 2 outputs and one input. Might be useful. @Sunbeast could you provide a link to the source of your info?

Apparently this is done using a Neuro cable, which is a TRRS cable included with Source Audio pedals for Hub connection. Apparently setting the control jack for Ring MIDI connection for one.
I learned about it through posts from Gibs210 (an employee of Source Audio) on Talkbass, starting in this post then recommended many times subsequently for C4 users looking for the easiest solution to MIDI control: source audio c4 | Page 138 |

Here is the original post from an SA employee: source audio c4 | Page 138 |

Not a lot of info, he is mentioning the neuro cable, though. That’s an 1/4 trs to 1/8 trs cable. He doesn’t say which port to use, but since the neuro cable is usually used to connect to input 2, that’ll be my first guess.

Well apparently my posts with links have been hidden on here and it won’t let me post another link (perhaps because they think linking to info about a “competing” product is automatically spam even as I sold my DMC controller for the clearly superior MC6!). I tried to post another link to a comment from the Source Audio employee specifically instructing to use the Control Input on the C4 for this new functionality

The Control Input port on the C4 is TRRS, but apparently upon re-reading the new functionality works with a TRS cable

Yes upon re-reading some Talkbass posts the new functionality works via TRS cable, even as the Control Input on the C4 is TRRS

Why would someone flag this? Maybe it’s someone of SA who wants us tu buy a neuro hub :wink:. Would you pm me that other link?

It’s an automatic forum spam check so somehow that post got flagged because the same link got shared across multiple posts. I have restored the post.

It won’t let me post Talkbass links anymore, and I can’t find a PM feature on this forum? Sorry. I can copy and paste what Gibs said on Talkbass though (here he is referencing the SA Aftershock in this post, which only has 6 presets, but in other posts he says this new control option accesses all presets on the C4 and other One-Series pedals as well via CC messages):
“Latest update for the micro allows you to use the included neuro cable connected to the control input on the one series, and the multi jack on the micro. Set the jack to midi ring, and use the “SOne” device driver and set the midi channel to match, though I believe disaster area suggests using midi channel one for this setup for certain pedals, I think the aftershock is fine on any of the 4 available from the micro to send to. This will give you access to the six onboard presets.”
In a different post he mentions that the Control Input is normally not MIDI compliant because of the grounding scheme, so not sure what the Disaster Area guy figured out with that “SOne” setting: " The TRRS port is not midi compliant, it lacks the isolation needed for the midi standard. That said, we’re working on an adapter to allow for direct midi control via the TRRS port for the one series pedals without a midi din port."

OK thank you. I’m not very optimistic, though. If it works at all, we will probably run into ground loop issues.

So the C4 manual states:

Input 2 as a Neuro App Data Input.
The ring contact on Input 2 acts as a data connection for the Neuro App. Connect it to your mobile device using a stereo (TRS) ¼” cable.

So it sounds like a standard 1/4” TRS cable from Omniport to Input 2, with the Omni set to ‘MIDI out - ring active’ is what’s required. Will try it when time permits!

Not sure if you missed my post above, but at least the DMC approach requires using a TRS into the 1/8” Control Input as opposed to the Neuro App input. Not sure what the Neuro App does to allow the 1-way control (not MIDI), but at least in this case it seems the Control Input is the right path for MIDI control