Building A Velocity Sensitive Keyboard

January 29, 2013 by Brian Benchoff 10 Comments

keys

Cheap toy pianos don’t usually have MIDI, and getting a velocity-sensitive keyboard from something out of the toy aisle at Walmart is nearly out of the question. If you’re willing to tear one of these toy pianos apart and build your own control electronics, though, the sky is the limit, as [JenShen] shows us with his home built velocity sensitive keyboard.

Usually, velocity-sensitive keyboards have two buttons underneath each key. By having a microcontroller measure the time difference between when each button is pressed, it’s possible to sense how fast each key was pressed. [JenShen] took the idea of a velocity-sensitive keyboard in another direction and instead used a force sensitive resistor strip, cut up into many pieces to provide velocity and aftertouch data.

[JenShen]’s keyboard adds these resistive buttons to the button matrix he already made. The result is a very inexpensive velocity sensitive keyboard with aftertouch, an impressive feat for an Arduino and only a few components.

You can check out the keyboard in action after the break.

Continue reading “Building A Velocity Sensitive Keyboard” →

Duct Tape Bagpipes

January 29, 2013 by Eric Evenchick 37 Comments

Looking to build your own instrument out of plumbing and tape? [Scott] made his own set of Membrane Bagpipes out of PVC pipes, a plastic bag, and duct tape.

Bagpipes are made out of a few parts. The drones are pipes that are tuned to play a single note. They are tuned by the fixed length of the pipe. The chanter is a tube with finger holes. This lets you play various notes depending on which holes you cover. The blowpipe is used to fill the bag with air that will pass through the membranes on the drones and chanter. Finally, there’s the bag which stores air.

[Scott]’s build uses PVC for the drones and chanter. The membranes are made out of cut up bits of plastic bags. Some crafty duct tape work makes up the bag, and seals it on to the various parts. A check valve is used to stop warm, duct tape flavoured air from blowing back into your mouth.

It’s pretty amazing what people can do with a few rolls of duct tape. The pipes aren’t exactly in tune, but they certainly work. Check out a video of them in action after the break.

Continue reading “Duct Tape Bagpipes” →

Raspberry Pi Becomes A Guitar Effects Processor

January 28, 2013 by Brian Benchoff 34 Comments

One of the more interesting use cases for the Raspberry Pi is exploiting its DSP capabilities in interesting ways. There’s a lot of horsepower inside the Raspberry Pi, more than enough to do some very interesting things with audio, all while being powered by a small wall wart adapter. [Pierre] over on the Pure Data mailing list has a proof-of-concept working that uses the Raspi as a guitar effects processor. The results are very encouraging – [Pierre] is able to use his Raspi as a delay, pitch shifter, and of course a classic flanger, phaser, and chorus with a latency of about 16 ms.

There are a few steps necessary to get low latency with the Raspi’s audio interface. [Pierre] is running his Pi headless, and allocated more RAM to the CPU.

If you’d like to try this out for yourself, [Pierre] has a tutorial for setting up Pure Data with the Raspberry Pi. He’ll be updating his blog soon with more tutorials and verified USB audio interfaces later.

Check out the processor in action after the break.

Continue reading “Raspberry Pi Becomes A Guitar Effects Processor” →

Tired Of Playing The MacBook? Play The Raspberry Pi!

January 21, 2013 by Brian Benchoff 29 Comments

pithingy

Hit up any club, party, or get together where musicians are present and you’ll probably find a DJ booth stacked to the gills with faders, various MIDI devices, and a MacBook. However abundant an OS X-based DJ platform is, we haven’t heard hide nor hare of a Raspberry Pi being used as a sequencer, MIDI device, or MaxMSP box.

[James] over at Illuminated Sound put together a great tutorial for making all those cool electronic music devices play nice with a Raspberry Pi. He used a Novation Launchpad, an 8×8 MIDI controller that can act as faders, a keyboard, or even a functional equivalent to the pads on an MPC.

Hardware is nothing without software, so [James] used Puredata and libusb to turn the MIDI data into notes and audio effects.

[James] added a download that includes the Launchpad driver and a Puredata sketch to test everything out. You can see how it all fits together in the video after the break.

Continue reading “Tired Of Playing The MacBook? Play The Raspberry Pi!” →

Turning A Broken Bass Into A Headless Bass

January 11, 2013 by Brian Benchoff 5 Comments

bass

A while back [Michael] inherited a broken bass guitar from a friend. The headstock for this bass was cracked right down the middle, and the friend attempted a repair with a bolt and a couple of washers. After trying to figure out what the addition of a bolt was trying to accomplish, [Michael] set to work repairing this bass and ended up doing a headless conversion.

A headless bass, just as the name implies, does away with the headstock and moves the tuners to the other side of the guitar – in [Michael]’s case, right below the bridge. After sawing off the broken headstock above the truss rod, [Michael] made a string retainer and bolted it on to the remainder of the neck.

The tuners had to be moved, of course, so [Michael] routed out a section of the body below the bridge. Four holes were drilled and the original tuners slipped right in. The result is a perfectly functional bass that would fit right in to the tour van of an 80’s metal band.

You can check out [Michael]’s bass down in the pocket.

Continue reading “Turning A Broken Bass Into A Headless Bass” →

Reading Piano Rolls Without A Player Piano

January 7, 2013 by Brian Benchoff 22 Comments

detection-example

A while back, [Jacob] played around with a player piano. After feeding a roll into the machine and trying to figure out how a fifty year old machine using hundred year old technology can replicate a skilled pianist, he decided to take a crack at decoding piano rolls for himself. He came up with a clever way of doing it over Christmas break, using a camera and a few bits of OpenCV.

The old-school mechanics of a player piano use a bellows and valve system to suck air through dozens of holes, making the action hit a string whenever a hole is present in the piano roll. To bring this mechanism into the modern age, [Jacob] pointed a video camera at the active part of the piano roll and used OpenCV to translate holes in a piece of paper to a MIDI file.

The synthesized version sounds just as good as the original paper scroll-based version, as seen in the video after the break. There are a few sync issues in the video and the resulting MIDI file isn’t in the right key, but that’s easily fixed by anyone willing to replicate this project.

Continue reading “Reading Piano Rolls Without A Player Piano” →

Put That Headphone Jack Anywhere You Want It

December 25, 2012 by Mike Szczys 17 Comments

yamaha-keyboard-headphone-jack-hack

Check out this brand new Yamaha keyboard. The fact that we’re seeing the guts means that [Todd Harrison] can kiss his warranty goodbye. But by now you should know that he doesn’t look to others when something goes wrong with his electronics. This time around he’s not repairing anything. He didn’t like having to plug in headphones on the rear of the keyboard. He cracked it open and relocated the headphone jack to a more convenient location.

As you can see, there’s a ton of room inside once the MDF base which holds the speakers and some sounding boxes has been removed. While he’s in there he takes a good look at the mechanics of the keys. They’re weighted with metal rods (seen above) to help the electronic instrument feel more like an acoustic version to the player. But he doesn’t neglect the chance to gawk at all the electronics as well.

After pulling out the PCB that has the headphone jack on it he goes to work with a solder sucker. With the solder gone he cuts through the glue that holds the jack on the board. All that’s left is to solder some wire in its place and give it a nice project box as an enclosure. To complete the hack he mounts the box on the MDF base and now the headphones connect on the front. See the entire process in the video after the break.

Continue reading “Put That Headphone Jack Anywhere You Want It” →