MIDI is a great tool for virtually any musician. Unless you’re a keyboard player, though, it might be hard to use it live. [Evan] recently came up with a great solution for all of the wistful guitar players out there who have been dreaming of having a MIDI interface as useful as their pianist brethren, though. He created a touchless MIDI controller that interfaces directly with a guitar.
Comedian Mitch Hedberg had a theory about Pringles potato chips. His theory is the company formed to make tennis balls. But instead of a truckload of rubber, someone accidentally sent them potatoes, so they made the best of it. Certainly the Pringles can is an iconic brand all by itself. The cans also have a lot of hacker history, since they are commonly used for WiFi cantennas (even though it might not be the best choice of cans). People also use them to build pinhole cameras, macro lenses, and a variety of cannon-like devices.
[Ian H] uses the short Pringles cans to build a drum kit. Clearly, the little cans aren’t going to make very much sound on their own, but with a piezo speaker element used in reverse, the cans become touch sensors that feed an Arduino and drive a MIDI device. You can see a video of the result, below.
Do any of you stay awake at night agonizing over how the keytar could get even cooler? The 80s are over, so we know none of us do. Yet here we are, [James Cochrane] has gone out and turned a HP ScanJet Keytar for no apparent reason other than he thought it’d be cool. Don’t bring the 80’s back [James], the world is still recovering from the last time.
Kidding aside (except for the part of not bringing the 80s back), the keytar build is simple, but pretty cool. [James] took an Arduino, a MIDI interface, and a stepper motor driver and integrated it into some of the scanner’s original features. The travel that used to run the optics back and forth now produce the sound; the case of the scanner provides the resonance. He uses a sensor to detect when he’s at the end of the scanner’s travel and it instantly reverses to avoid collision.
A off-the-shelf MIDI keyboard acts as the input for the instrument. As you can hear in the video after the break; it’s not the worst sounding instrument in this age of digital music. As a bonus, he has an additional tutorial on making any stepper motor a MIDI device at the end of the video.
If you don’t have an HP ScanJet lying around, but you are up to your ears in surplus Commodore 64s, we’ve got another build you should check out.
[Folkert van Heusden] sent us in his diabolical MIDI device. Ardio is a MIDI synthesizer of sorts, playing up to sixteen channels of square waves, each on its separate Arduino output pin, and mixed down to stereo with a bunch of resistors. It only plays square waves, and they don’t seem to be entirely in tune, but it makes a heck of a racket and makes use of an interesting architecture.
Ardio is made up of three separate el cheapo Arduino Minis, because…why not?! One Arduino handles the incoming MIDI data and sends note requests out to the other modules over I2C. The voice modules receive commands — play this frequency on that pin — and take care of the sound generation.
None of the chips are heavily loaded, and everything seems to run smoothly, despite the amount of data that’s coming in. As evidence, go download [Folkert]’s rendition of Abba’s classic “Chiquitita” in delicious sixteen-voice “harmony”. It’s a fun exercise in using what’s cheap and easy to get something done.
Sequencers allow you to compose a melody just by drawing the notes onto a 2D grid, virtually turning anyone with a moderate feel for pitch and rhythm into an electronic music producer. For [Yuvi Gerstein’s] large-scale grid MIDI sequencer GRIDI makes music making even more accessible.
Instead of buttons, GRIDI uses balls to set the notes. Once they’re placed in one of the dents in the large board, they will play a note the next time the cursor bar passes by. 256 RGB LEDs in the 16 x 16 ball grid array illuminate the balls in a certain color depending on the instrument assigned to them: Drum sounds are blue, bass is orange and melodies are purple.
Underneath the 2.80 x 1.65 meters (9.2 x 4.5 foot) CNC machined, sanded and color coated surface of the GRIDI, an Arduino Uno controls all the WS2812 LEDs and reads back the switches that are used to detect the balls. A host computer running Max/MSP synthesizes the ensemble. The result is the impressive, interactive, musical art installation you’re about to see in the following video. What better tune to try out first than that of Billie Jean whose lighted sidewalk made such an impression on the original music video.
[Opificio Sonico] has been at the Lego-based robot music making business for a while now, and it shows. He’s released four videos on YouTube (all inlined below) and each shows a definite evolution of his style and the Lego ‘bots technical range.
Episode 4, a cover of Daft Punk’s “Alive”, is clearly the most polished. A sliding platform goes enables a Lego “Toa Mata” figure to play the melody on some kind of iDevice (?). The ‘bot playing the DS to hit its one note repeatedly with the stylus, and has an easier job thanks to Daft Punk’s compositional “efficiency”. Episode 3, Depeche Mode’s “Everything Counts” is fantastic, partly because he’s using piezo-miced junk as percussion (as did DM themselves) and partly because of the sliding stylophone. But watch them all.
[gutbag] is a guitarist. And guitarists are notorious knob-twiddlers: they love their effects pedals. But when your music involves changing settings more than a few times in the middle of a song, it can get distracting. If only there were little robot hands that could turn the knobs (metaphorically, sorry) during the performance…
Tearing into his EHX Pitch Fork pedal, [gutbag] discovered that all of the external knob controls were being read by ADCs on the chip that did all of the processing. He replaced all of the controls with a DAC and some analog switches, coded up some MIDI logic in an ATmega328, and built himself a custom MIDI-controlled guitar pedal. Pretty slick, and he can now control it live with his iPad, or sequence the knobs with the rest of their MIDI system.
This wasn’t [gutbag]’s first foray into pedal automation, however. He’d previously automated a slew of his pedals that were already built to take control-voltage signals. What we like about this hack is the direct substitution of DAC for potentiometers. It’s just hackier. (Oh, and we’re envious of [gutbag]’s lab setup.)
This isn’t the first time we’ve covered [gutbag]’s band, Zaardvark, either. Way back in 2013, we featured an organ-pedal-to-MIDI hack of theirs. Keep on rockin’.