Building A Control Surface

[Eccentrica]

I'm about to embark on something quite insane (well for me anyway) I'm going to build my own large format midi control surface (mixing console) specifically for use in the studio and specifically with reaper using doepfer circuits. i was wondering if any one had any experience with these and Reaper or if there was any problems i might come into if any that you guys can think of?

[helpdeskeddy]

What's the reason that you want to build it yourself?
I know the doepfer stuff is not quite cheap and DIY in a nice box can be quite a lot of work...
I don't want to discourage you. It's also a lot of fun... But it's good to know why you're doing this.

Are you gonna use faders and/or rotary encoders? Motorized?
Any displays?
How are you going to make the housing/case?

Actually, when I'm thinking about this I become very excited:)... (I've got some experience DIY-ing...)
So, please keep us informed...

Eddy

[Guod3]

Anyone interested in DIY midi control surface needs to study
http://www.ucapps.de/
Midibox is the REAPER of the DIY midi hardware projects world!

[tspring]

This summer, my son and I built a simple MIDI controller around one of the Doepfer modules. It has 4 joysticks (with a pot on the x and y axes of each pot)and 8 knobs. It's single unique feature is that the four joysticks are placed close together so that you can put one hand on them, and move them all at once. That means you can control 8 parameters on a synth simultaneously with one hand. And up to 16 parameters can be controlled in total.

Working with the Doepfer is easy. Believe it or not, the hardest part of the project was making the top panel of the case (black plexigas) and getting the holes in the top to line properly with the joystics, which were mounted on a circuit board suspended beneath the panel .

I thought about building the controller using one of the Stamp PICs, because they are cheaper, and because the Stamp modules can be programmed to do almost anything that you can dream up. Actually, the Doepfer is not really programmable. It has built in programming to convert voltage readings from 16 switches/pots to midi CC and Sysex commands + data. You select a bank (via DIP switch) that has pre-selected commands that are associated with each of the Doepfer's 16 analog input channels. Anyway, all of the postings about DIY projects based on the Stamp that I saw seemed to indicate problems with getting the on-board serial I/O circuitry modified/programmed so that it worked adequately as a midi in or out.

So we went with the Doepfer. The only other parts that I had to buy were joysticks and potentiometers. I powered it with a 9V wall-wart power supply salvaged from a discarded answering machine. Electronics skills needed were semi-proficiency in soldering. Knowledge requirements were minimal. If you know what ground means and how a potentiometer works then you can do it.

T

[Guod3]

Yes, its really important to match the level of involvement one wants to have with the goals. Pre-built, preprogrammed module devices will get you results quickly.
On the other hand, Midibox (built a one in 2002, still use it) has the possibility of tweaking the code and other configuration files for extreme flexibility and customisation. All source code is open source. It is also possible to purchase pre programmed chips and avoid any involvement with code or flash programming (great entry level for beginner).
Midibox is actually a set of open source, open design modules that can be arranged in any combination.
Various design configurations are there for those that want to "work from plan".
Projects include
control surfaces, (vpots, pots, motorised faders, etc.)
midi controlled digital and analog I/O
midi digital synths (FM and SID based)
Various LCD graphic and text display options.
Open source, custom RTOS (called MIOS)
Great community vibe.
3rd party vendors make purchasing parts or even kits very easy.
Extremely cheap!

[Mark90]

Would totally agree with Guod3, midibox rocks..
Built my own in in 2003 mainly because I couldn't afford a
control surface (at that time they were quite expensive)
The great thing about the ucapps stuff is that your creation
can be whatever you want it to be.

If you know what end of a soldering iron to use then definitely
give it a look...

[LCipher]

I built a midibox awhile ago. Fun project. Lots of work though!

http://members.surfbest.net/mc5021x@surfbest.net/midibox1small.jpg

[tspring]

Lcipher,

Nice looking project. But I'm curious about the external connector on your project box. It doesn't *look* like MIDI or USB. Whats going on?

T

[flight]

Lcipher,

Nice looking project. But I'm curious about the external connector on your project box. It doesn't *look* like MIDI or USB. Whats going on?

T

Looks like a serial port connector. Ah, those were the days...
:p

[LCipher]

It is a serial port connector (DB9) wired to midi. I actually wired it to plug directly into my delta 1010 card.

So it IS midi, but I just chose a totally non-standard cable scheme ;) It also kept the cable clutter down.

[Guod3]

Midibox controllers have the option to run at a higher data rate than midi, that is 38400baud which is standard for a COM port (RS232).
Using a free COM port midi driver on the host PC, this saves on a dedicated midi-in port on the DAW.

[nerdfactormax]

I'd be mad keen to build my own control surface if I could find a place to source cheap motorized faders, but every time I look into it, I keep thinking I should just buy a BCF2000 or 2.

[tspring]

Midibox controllers have the option to run at a higher data rate than midi, that is 38400baud which is standard for a COM port (RS232).
Using a free COM port midi driver on the host PC, this saves on a dedicated midi-in port on the DAW.

Aha. That is very interesting. It implies that there are drivers available that can pass midi data back and forth via the com port. Can anybody provide links to a source?

When we were scoping out PICs and support modules, we also thought about trying to do midi via USB. I abandoned this approach because I couldn't figure out how to deal with the driver that would be required.

Is it possible to give a relatively simple explanation of how a driver supporting midi data transfer over RS-232 or USB works? More to the point, lets say that I have grabbed a few bytes of data from the com port buffer, and that it has been converted to the proper format for midi messages. How does one get the data into the system midi stream? Not that I believe I can/would write a driver...I'd just like to understand the principles.

T

[Guod3]

When using the RS232 to carry midi, it is the same serial data, just at a different baud rate. The COM port data is presented to the host software by a driver that makes it look like any other midi driver.
For more details and links to drivers:
http://www.ucapps.de/
http://www.ucapps.de/midibox_to_com.html
http://www.ucapps.de/mbhp_ltc.html

[TexasFury]

Are inexpensive motorized faders the only stumbling block to a DIY control surface? I always thought current control surfaces are extremely expensive for what is a very simple device. Hell you can a buy an entire car (which takes an extreme amount of engineering compared to a CS) for less.

[Guod3]

It should be noted that behringer have some inexpensive control surfaces BCF2000 and BCR2000.
DIY control surfaces may or may not be expensive depending on the configuiration.
The smart reason for a custom control surface is to provide for controls and buttons that serve a particular workflow for producers or performance style for musicians.

In my experience with the BCF2000 (w/ motorised faders) is really good but successfully emulating a DAW mixer in a CS is a very difficult task in practise.

You really need good visual feedback with CS's

There is no point in having a VST paramter under the control of a Vpot if you cant see and instinctively know what the knob under your hand is actually modulating.
This is why I have a whole DIY CS dedicated for one VSTi (Access Virus).