MIDI Sequencer/controller

June 13, 2009 by Gerrit Coetzee 12 Comments

lenonluks

Reader, [Lennon Luks] made a really slick MIDI sequencer/controller for his senior design project while studying at Western Carolina University. It has a grid of 64 LED buttons, 8 knobs, and a display with navigation buttons that allow him to sequence tracks with or without a computer. The controller is based off an ATmega644 and is programmed in C. [Lennon] clearly explains the inner workings of the project in detail on his website and has included a good number of pictures. [Lennon] made a nice video of the project which can be seen after the jump.

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Irregular Incurve Robotic Instrument

May 12, 2009 by Eliot 13 Comments

irregular_incurve

The Irregular Incurve is a robotic instrument built by [Xiaoyang Feng] as part of his ITP thesis work. It’s a MIDI instrument with an array of 12 strung bows mounted to a curved shower rod. The end of each bow has a tuning key. The strings are each picked using independently mounted arms. One servo controls the downward motion of the pick while the other controls the rotation of the shaft. A damper is also attached to each arm. The string vibrations are transferred to a spruce soundbox under the bridge. Below you can see a video of Gizmodo playing with it at the ITP show. Check out [Xiaoyang]’s Flickr set for images of the build process plus some early videos of the mechanism.

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AXiS-49 Teardown

March 31, 2009 by Eliot 5 Comments

cthruteardown

We touched on harmonic table MIDI controllers when [aris] was building one. [Ken Rushton] has one of C-Thru’s commercial keypads, the AXiS-49, and disassembled the device to show how it works. A PIC18F2450 microcontroller provides the USB interface and is connected to a dsPIC33FJ128GP310 digital signal controller which decodes the keypresses. The membrane buttons are made with two concentric graphite disks that touch gold contacts. The microcontroller measures the time between the two points contacting to determine the button velocity. monome button clones also use circular contact pads, but cannot calculate velocity because they only have one element.

[via Matrixsynth]

Generating G-code With Common Lisp

February 1, 2009 by Eliot 10 Comments

gcode

Ruin & Wesen are a two person shop creating specialized music gear. As part of their recent MIDI Command development, they got into case manufacturing. They purchased a mini CNC mill to cut the aluminum cases. Unhappy with the software options provide [Wesen] decided to write his own G-code generator. G-code is part of the numerical control used to command CNC machines. He implemented his interpreter using the language he’s most familiar with: Common Lisp (not surprising if you notice the website’s backend). The post covers the design philosophy used and some of the problems that came up. We look forward to future releases since the interpreter can generate milling code using processing.org sketches and cut PCBs directly from Eagle.

You may remember Ruin & Wesen from when they shared their Eagle layout videos.

[Thanks fbz]

Passive MIDI Foot Switch

January 20, 2009 by Caleb Kraft 12 Comments

foot

[Matt] was looking into some software that allows him to use his audio card as a means to control analog audio devices. After seeing how it worked, he got an idea to try to do the opposite. He is sending a signal into his audio input, and piping it to a pice of MIDI software. The input he has chose is a foot switch. To create the signal, he simply needed to supply voltage while the switch was depressed. You can see above that he used a battery and a simple contact switch to send the signal. He then piped it to a virtual MIDI port using Maple Virtual MIDI Cable. Unfortunately, this isn’t suitable for knobs, but that may be next on his list.

CUIduino, Arduino With True USB Support

January 17, 2009 by Eliot 11 Comments

cuiduinotop

The CREATE USB Interface (CUI) was a project that came out of UC Santa Barbara around the same time the Arduino was being developed. It has a USB port, a PIC18F4550, and a prototyping area. It was designed to enable easy interfacing with the real would through many A/D inputs and general I/O ports. It supports both OSC and MIDI-over-USB natively. The biggest difference between the CUI and the Arduino is its USB support. The Arduino uses an FTDI chip to create a serial interface to its onboard AVR. The CUI’s PIC has native support for USB. That means you can have the CUI appear to be any USB HID device you want: keyboard, mouse, game controller, etc.

The Arduino has a friendly development environment and a large following though. CUI create [Dan Overholt] decided to add an ATmega168 to his board to get the best of both worlds, the CUIduino (scroll down). It can be programmed just like any other Arduino compatible device, but the having the CUI parent means your Arduino project can behave like a native USB HID gadget.

[Thanks Peter]

Generating MIDI With Ruby

January 16, 2009 by Eliot 4 Comments

[vimeo 720761]

[Giles Bowkett] has been working on a music library for Ruby called Archaeopteryx. He describes it as a “Ruby MIDI DJing/live-coding thing“. In the video above, He’s using it to generate and then morph rhythms. The Ruby code is directly controlling the step sequencer in Reason. It’s an interesting approach to music development. The video above gives a full intro to the probability approach to generation. To really get a feel for the library, we suggest you watch his presentation from RubyFringe. It shows him playing music by editing a live block of code. Check out his Vimeo feed for many more demo videos.

[via CDM]