Modifying a controller to add an audio interface

I’m thinking about adding a small audio interface (2 channel) to my Novation Impulse controller to give me a bit more flexibility with gigs, etc.I’d like to get this down to the laptop, one keyboard, and a couple of cables for things like church (where I play piano mostly).

  • RIght now when I play I’m using the Impulse, the laptop, and a MOXF8, but I dont’ want to haul the MOXF8 around when I don’t need to. Sometimes I use my Hammond SK1, which is great for organ and some EP’s, but not nearly as flexible as a synth or controller with layers, splits, etc.) .
  • The Impulse is light and though I haven’t opened it up I think there could be enough room for a disembodied small audio interface (maybe one of the Behringers). I figure the case and the jacks are probably the heaviest part of the interface, and since the jacks will be mounted it should be stable.
  • It will be used with my laptop
  • I dont’ want to haul around my MOXF8 (which I generally use with my laptop for audio and MIDI, and the Impulse as a second keyboard)
  • I figure I’ll have to graft on a second set of jacks (MIDI, audio, USB) as I don’t plan to integrate what’s there already internally (e.g., two USB’s), including separate power if need be.

My other option is to find a synth with an audio interface (maybe one of the small Yamaha, MODX/MX type synths).

Anyone else tried this? Any points/hints?

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That sounds like what I do. In order:

  1. Midi Controller with 5-pin DIN Midi Output
  2. Midi 5-pin to USB converter (I’m terrified of Midi over USB as it seems to arbitrarily boot up differently sometimes. Maybe this is a personal problem?)
  3. Laptop
  4. USB DAC (digital to audio converter) with XLR outs to Mixer

If you really want to go light, use the audio outs of the laptop by converting the 1/8" TRS to L&R balanced XLRs with transformers. Rane Notes 110 has some interconnection diagrams.

Behringer (and others, I’m sure) have some interfaces with both MIDI (5-pin) IO and Analog IO to USB.

The simplest solution might be to go from Novation to Laptop via USB (just make sure it works all the time), then use the laptop audio outs. With modern laptop audio, I probably cannot tell a difference between the laptop audio and an inexpensive interface. Maybe others can, IDK.

Many low cost midi key controllers these days do not have 5-pin outputs, and no power input. Everything is reliant on USB midi and power. I’ve been using USB for nearly a decade, and found early on that not all USB cables are the same. I truly had no problems in years with thousands of gigs and rehearsals using heavier cables.
My research sometime back:


Good information about USB cables. My issue is not the cables not working (so far as I know), but the OS getting involved and changing the USB ID designations. Even if I don’t change physical USB ports on the PC, sometimes Cantabile cannot find the device because OS (or something) has “incremented” the device. Then, I’ve got to go into Tools/Options/MIDI Ports and add to old device. Maybe I was doing things wrong, maybe this is a solved legacy issue, etc, but I’ve standardized on 5-pin DIN for now.

Looks like the thread was hijacked (USB cables, etc.). I have now issues with USB MIDI

What I’m trying to do is add an audio interface to a controller that doesn’t have one, and I’m wondering if anyone has done this as we do have some electronics DIY folks on this forum.

Dont want to use the laptop audio outs for multiple reasons (again, not to hijack this thread as these have been covered here and on other forums for many years).

I do a fair amount of DIY audio work and that would be quite a trick to add audio outs to a midi controller that does not already have that feature. A separate, small DAC with USB would work, too. Or maybe I’m not following what you are trying to do…

I’m assuming you have “no” issues instead of “now” issues with USB MIDI.

Sorry, I’m not sure what do you mean. You want to put a (DYI or not) audio interface into a controller, say a keyboard with MIDI-over-USB connector. I am right?

HI Pat,

I strongly recommend you try one of the $20 Behringer UCA-202 USB Audio interfaces. They perform well latency wise and are just slightly noisier than the UMC202HD’s I use. They only have RCA outputs for left and right channel. I use RCA male to 1/4 TS female adapters so I can plug regular guitar cables into it. There is also a volume knob and indicator lights. The USB coming out of it is just a cable - not an input.

In the below photo you can see them fastened (3M heavy duty two sided tape) to a Dell 2 in 1 11" laptop. The RCA adapters are on the guitar cables.

They’re hard to see but there are two thumbscrews on both sides the laptop. I made adjustable metal latches that hold the laptop on the keyboard. The laptop folds back so the screen is angled and the UCA-202 is behind.

I use the MIDI Sport Uno with keyboards that don’t have USB

The picture above doesn’t solve the problem - I’m trying to get rid of things not add them, and not looking to go super cheap (that’s not a requirement).

Already have a separate audio interface. Want to incorporate one into my Novation Impulse 61. Don’t “integrate” it at all with the controller - just add it in in parralel.

Open the controller, mount the audio interface inside the controller, have separate audio outs and a separate USB connections on the back end, connect it all via two USB cables and audio cables to the mixer/amp/DI.

Very similar to my setup: Sabrent USB Hub, MidiSport 2x2, and Lexicon Alpha.

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I was thinking that you could mount the usb hub and UCA-202 internally. I was displaying the above system because it is self contained. I can walk onstage with it, get handed a cable coming from an amp and start playing. Runs off the Dell’s battery for about 1.5 hours of playing

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Sweetwater has the Behringer UCA222 for $9.99 (normally $30). This might be a good priced item to trial.

A Sabrent USB Hub and the Behringer USB Analog IO are pretty small. Those could be easily velcroed to the top of the controller. As you say, maybe they could be placed inside the controller cavity?

You don’t need an audio interface as this would buy you nothing. A DAC would also do no good. You need an internal sound module to convert MIDI to actual audio sounds. It needs to be small enough to fit into your controller and you would need to integrate the MIDI data of your controller to control the output sounds that you want.

My recommendation is to find an actual small keyboard that sends sounds and also has a MIDI interface and not try to pull apart and build your own solution out of a MIDI only keyboard. It will likely be less expensive. For me, I would look into the Roland VR-Combo (AKA VR-09). I have one and it is lightweight and has both audio and MIDI interface.