Circuit Bent Casio SK-1 Gets An Arduino Brain

February 5, 2018 by Tom Nardi 28 Comments

The Casio SK-1 keyboard is fairly well-known in the “circuit bending” scene, where its simple internals lend themselves to modifications and tweaks to adjust the device’s output in all sorts of interesting ways. But creating music via circuit bending the SK-1 can be tedious, as it boils down to fiddling with the internals blindly until it sounds cool. [Nick Price] wanted to do something a bit more scientific, and decided to try replacing his SK-1’s ROM with an Arduino so he could take complete control it.

Replacing the ROM chip with header pins.

That’s the idea, anyway. Right now he’s gotten as far as dumping the ROM and getting the Arduino hooked up in place of it. Unfortunately the resulting sound conjures up mental images of a 56K modem being cooked in a microwave. Clearly [Nick] still has some work ahead of him.

For now though, the progress is fascinating enough. He was able to pull the original NEC 23C256 chip out of the keyboard and read its contents using an Arduino and some code he cooked up, and he’s even put the dump online for any other SK-1 hackers out there. He then wrote some new code for the Arduino to spit data from the ROM dump back to the keyboard when requested. In theory, it should sound the same as before, but with the added ability to “forge” the data going back to the keyboard to make new sounds.

The result is what you hear in the video linked after the break. Not exactly what [Nick] had in mind. After some snooping with the logic analyzer, he believes the issue is that the Arduino can’t respond as fast as the original NEC chip did. He’s now got an NVRAM chip on order to replace the original NEC chip; the idea is that he can still use the Arduino to reprogram the NVRAM chip when he wants to play around with the sound.

We’ve covered some pretty fancy circuit bent instruments here in the past, but if you’re looking for something a bit easier to get your feet wet we ran a start-to-finish guide back in the Ye Olden Days of 2011 which should be helpful.

Continue reading “Circuit Bent Casio SK-1 Gets An Arduino Brain” →

Flexiphone Rises From The Ashes Of Broken Instruments

February 2, 2018 by Adam Fabio 7 Comments

The mechanics of an old Rhodes Piano, and a set of chromatic saucer bells rescued from a reed organ. What do these two things have to do with each other? If you’re [Measured Workshop], they are the makings of a new instrument. The Flexiphone is a transposable instrument with a piano keyboard and interchangeable sound source.

The Rhodes is a great stage instrument. Unlike a piano with strings, it uses tines mounted above the key mechanism. It is also relatively compact for an analog instrument. This made it perfect as a donor for the Flexiphone’s keyboard. [Measured Workshop] cut they mechanism down to 30 keys, just under 2 octaves. The key mechanism was also cleaned up and restored with new felt.

The sounding portion of the Flexiphone is a set of chromatic saucer bells. The bells are mounted on a felt covered threaded rod, which itself sits in a wood frame. The bell frame sits on top of the base in one of three slots. Each slot is a halftone transposed from the last. Simply moving the bells allows the player to transpose the entire instrument. The bells and their rod frame can also be completely removed and replaced with any other sound source.

The Flexiphone sounds great — sometimes. As [Measured Workshop] says, bells contain many harmonics. playing single or double notes sounds rather sweet, but chords can sometimes become a shrill assault on the ears. Still, it’s an awesome hack with plenty of potential for future mods.

Continue reading “Flexiphone Rises From The Ashes Of Broken Instruments” →

Keeping Magnetized Marbles From Stopping The Music

February 2, 2018 by Dan Maloney 18 Comments

Take a couple of thousand steel balls, add a large wooden gear with neodymium magnets embedded in it, and what do you get? Either the beginnings of a wonderful kinetic music machine, or a mess of balls all stuck together and clogging up the works.

The latter was the case for [Martin], and he needed to find a way to demagnetize steel balls in a continuous process if his “Marble Machine X” were to see the light of day. You may recall [Martin] as a member of the band Wintergatan and the inventor of the original Marble Machine, a remarkable one-man band that makes music by dropping steel balls on various instruments. As fabulous a contraption as the original Marble Machine was, it was strictly a studio instrument, too fragile for touring.

Marble Machine X is a complete reimagining of the original, intended to be robust enough to go on a world tour. [Martin] completely redesigned the lift mechanism, using magnets to grip the balls from the return bin and feed them up to a complicated divider. But during the lift, the balls became magnetized enough to stick together and no longer roll into the divider. The video below shows [Martin]’s solution: a degausser using magnets of alternating polarity spinning slowly under the sticky marbles. As a side note, it’s interesting and entertaining to watch a musician procrastinate while debugging a mechanical problem.

We can’t wait to see Marble Machine X in action, but until it’s done we’ll just settle for [Martin]’s other musical hacks, like his paper-tape programmed music box or this mashup of a synthesizer and a violin.

Continue reading “Keeping Magnetized Marbles From Stopping The Music” →

Putting The Pi In Piano

January 31, 2018 by James Hobson 10 Comments

Working on a PhD in composition, [Stephen Coyle] spends a fair bit of time at his electric keyboard. Setting himself up to work can be a bit of a task, so he felt he could improve the process and make it easy as Pi.

Finding it an odious task indeed to use notation software, connecting his laptop to his keyboard is a must — avoiding a warren of wires in the move is a similar priority. And, what if he could take advantage of the iPad’s unique offerings too? Well, a Raspberry Pi Zero W running Ravelox — an RTP MIDI protocol — makes his music available on his network to record on whichever device he pleases.

Continue reading “Putting The Pi In Piano” →

Strumbot: The Guitar That Strums Itself

January 31, 2018 by Adam Fabio 13 Comments

[Clare] isn’t the most musically inclined person, but she can strum a guitar. Thanks to a little help from an Arduino, she doesn’t even have to do that.

She built the strumbot, which handles the strumming hand duties of playing the guitar. While [Claire] does believe in her strumbot, she didn’t want to drill holes in her guitar, so hot glue and double-sided foam tape were the order of the day.

The business end of the strumbot is a micro servo. The servo moves two chopsticks and draws the pick across the strings. The tiny servo surprisingly does a great job getting the strings ringing. The only downside is the noise from the plastic gears when it’s really rocking out.

Strumbot’s user interface is a 3D-printed case with three buttons and three LEDs. Each button activates a different strum pattern in the Arduino’s programming. The LEDs indicate the currently active pattern. Everything is powered by a USB power pack, making this a self-contained hack.

[Clare] was able to code up some complex strum patterns, but the strumbot is still a bit limited in that it only holds three patterns. It’s good enough for her rendition of “Call Me Maybe”, which you can see in the video after the break. Sure, this is a simple project, not nearly as complex as some of the robotic guitar mods we’ve seen in the past. Still, it’s just the ticket for a fun evening or weekend project – especially if you’re introducing the Arduino to young coders. Music, hacking, and modding – what more could you ask for?

Continue reading “Strumbot: The Guitar That Strums Itself” →

Students Hack An Unusual Violin

January 26, 2018 by Al Williams 18 Comments

[Sean Riley] is a violinist who had a problem. He wanted to play one particular piece, but he couldn’t. It wasn’t that he lacked the skill — he a doctoral student at the University of Texas and has two degrees in violin performance from The Julliard School. The problem was that “The Dharma at Big Sur” by [John Adams] is made for an instrument with six strings, while most violins only have four. So he did what any of us would do. He stopped by the local hackerspace and fabricated one. You can hear (and see) [Sean] performing with the instrument in the video, below.

The University of Texas operates “The Foundry” which is a hackerspace with all the usual items: laser cutters, 3D printers, and the like. It is open to all their students and staff. [Sean] needed some help with the engineering, and was lucky to find a mechanical engineering senior, [Daniel Goodwin], working at The Foundry.

Continue reading “Students Hack An Unusual Violin” →

Glitch Delays And Teensy Audio

January 11, 2018 by Brian Benchoff 4 Comments

With the release of the Teensy 3.6 and the associated audio processing libraries, it’s never been a better time to get into DIY synth and effects projects. [Scott] is a musician and maker of electronic musical instruments, so he decided to leverage the power of the Teensy and make a delay module that really can’t be done any other way.

The function of this delay module is somewhat similar to a multi-head tape-based delay, only it’s completely impossible outside of the digital domain. There are four ‘read heads’ on a circular buffer. The first three heads play small loops within the buffer at different speeds, one at the original speed, one at half speed (and an octave below) and one at double speed (and an octave above). The fourth head doesn’t loop, instead, it plays the delay buffer in reverse. There are, of course, handy knobs for setting the level of each ‘read head’.

This project is built around [Scott]’s port of the JUCE framework, a very powerful audio API that’s now well suited for laptop and embedded development. The files for this project are all available on the GitHub, and [Scott] plans to build an expansion module for CV control of all the parameters.

So, how does this glitch delay sound? Pretty good. The video below is just a tele into a looper pedal, and into the glitch delay. There are surely some ambient post-rock stars wetting their skinny jeans over this one, and it’s a great application of the Teensy’s audio processing power, to boot.

Continue reading “Glitch Delays And Teensy Audio” →