DIY DAW Controller Part 1: Choosing a MIDI Interface March 19, 2012 17:39 27 Comments

While wrapping up a mammoth "in-the-box" (computer-based) mixing session the other week, I vowed that I would not mix another project without some real faders under my fingers. Around this same time, an email subscriber tipped me off to the amazing open-source MIDI controller projects happening at midibox.org. Usually when people think MIDI they think of sequencers, keyboards, synth controllers, etc., but basically anything we do within a DAW (Digital Audio Workstation: ProTools, Cubase, Logic, etc.) can be controlled via MIDI. Indeed, many commercial control surfaces such as the Behringer BCF2000 are MIDI controllers. So, I've got the itch to make my own DAW controller. Great! Right now that's about all I've got. I know next-to-nothing about MIDI (or anything digital for that matter), and the MIDIbox website makes about as much sense as Greek Alphabet soup after a couple hours of browsing. I do know, however, that I've been through this before--I couldn't have told you whether audio signals were AC or DC when I built my first preamp. This time around, I'm going to document every step of my climb up the MIDI learning curve in hopes that it will take some of the mystery out of building your own DAW controller for those standing on the sidelines.

The Grand Vision

Since this is my first foray into MIDI, I'm planning on doing something fairly simple that would nonetheless break me out of the box for most of my mixing needs. There are 16 channels with pan, volume, mute, solo, and two aux sends each. That's 64 potentiometers total (16 slide + 48 rotary) and 32 switches.

dream mixibox

I'm still debating whether to use motorized or normal faders. It would be great to bring up a session in my DAW and have all of the faders snap to the corresponding positions. But motor faders are at least 5x more expensive than the normal ones. At this point, I'm leaning towards regular faders to keep the cost low. What do you think, will I regret this down the road? I've never mixed a project on a console or control surface without motorized faders before, is it a huge workflow problem not to be able to see where your levels are by looking at the faders?

Choosing a MIDI Interface

After a bit of research, the two MIDI platforms I'm looking at are Doepfer "Pocket Electronic," Doepfer USB64, MIDIbox 64, and MIDIbox LC.

Doepfer MIDI Interfaces

doepfer usb 64

The Doepfer products are appealing because they come as assembled, pre-programmed analog/MIDI interfaces. The Pocket Electronic puts out up to 16 channels via MIDI jack, while the USB64 can do up to 64 via USB. The Pocket Electronic seems like a great solution for a simple 8 faders + pan pots setup, but is decidedly short on channels for what I want to do. The USB64 offers enough channels and the option for digital inputs, which can be used for solo/mute switches. However, as far as I can tell, the USB64 can operate only in digital or analog mode, not both. Meaning I can have pots or switches, but not pots and switches. So, while the Doepfer units look very appealing from a digital newbie's perspective, they're not quite right for what I want to achieve.

The MIDIbox Platform

MIDIbox is an open source, modular MIDI platform that, while it's pretty confusing to me still, appears to be extremely flexible and scalable. Basically, there is a core "brain" circuit board that takes inputs from different modules (analog input module, digital input module, etc.) and turns them into MIDI I/O. People configure these modules in all sorts of ways with different firmware to create things like sequencers, DJ control stations, synth controllers, and of course DAW controllers. I'm sure that is a gross simplification of the MIDIbox system, but it's what I've been able to figure out so far. (Please feel free to correct or englighten me in the comments.) Circuit board layouts and firmware downloads are available at ucapps.de, and PCBs/kits are available from the MIDIbox shop. Of the many MIDIbox permutaions available, those that seem most applicable are the MIDIbox LC and the MIDIbox 64. The LC emulates the performance of the Logic Control / Mackie Control surfaces. If I were building the Ultimate DAW Controller, I would probably go with this as it allows for motorized faders, but since it uses the LC (or MCU) format, I'm not sure it's compatible with my DAW of choice, Reaper MIDIbox 64 is an older project, which appears to have been replaced by the MIDIO128, but since the Midibox Store stocks only the 64 PCBs at the moment I think I'll go with that. The 64 allows for up to 64 pots/faders, 64 switches, and 64 LEDs. More than enough to realize my "Grand Vision." There is also support for an LC-display and other stuff, but I'm going to ignore those for this project in the interest of keeping things simple.

What's Next

Right now I'm leaning towards the MIDIbox 64, but I'm going to continue reading about the MIDIbox platform until I start involuntarily piecing together interfaces in my head as a I fall asleep (usually a good sign I've reached a critical level of obsessiveness with a project). Once I settle on a configuration, I should be able to assemble a rough bill of materials and price out the project in Part 2. Until then, if you have any experience with MIDI DAW controllers, I'd love to get your feedback on which/how many controls you feel are essential for mixing, especially how you work with or without motorized faders.