[Chris] at PyroElectro sent in a great 8-part write-up of a miniature infrared theremin.

The theremin is based on a PIC microcontroller and an infrared distance sensor.  The build log goes through the theory of operations for the IR sensor and tone generation. [Chris] definitely does a great job showing the math that went into the design.

Although this project isn’t a true theremin because it operates on light like a few other projects we’ve covered in the past, it’s easier to play because of the hard-coded notes. The build does show some promise though – he could likely expand it to use more accurate ultrasonic sensors or use, “two proximity sensors, one for treble and one for bass like an accordion.”

The theremin is usually played with both hands providing a continuous pitch and volume. This project features hard-coded, discrete notes, so we’re wondering about the possibility of implementing MIDI on this IR theremin. The original MIDIbox was based on the same microcontroller as this project, so it’s definitely a possibility.

Check out the video of the theremin in action below.

Researcher and YouTube user [mspetitegeek] along with her lab mate [Tatsuhiko Itohara] have been fortunate enough to spend some time working with the HRP-2 humanoid robot from Kawada Industries. Their research has seemingly been focused on using the robot to create real-time interactions with humans for entertainment purposes, at the very least.

The program they created allows the HRP-2 to listen and watch its human counterpart while he plays the guitar in order to recognize a beat pattern. Once the robot catches on, it plays along on his Theremin, matching both notes and rhythm perfectly. Since the human operator is clearly playing at a fairly relaxed pace, we are curious to see a demonstration where the robot required to match a snappier tune – it could be quite interesting.

In the meantime, we’re content to just sit back and enjoy the Mogwai-esque tones of the HRP-2 rocking the Theremin.

Keep reading to see a short video of the HRP-2 in action.

[Ryan Challinor] is part of a group constructing a display for this year’s Burning Man festival that includes the Kinect, Ableton Live, and Quartz Composer. As the programming guru of the project, he was tasked with creating a method for his partners to utilize all three products via an easy to use interface.

His application is called Synapse and was inspired by videos he saw online of people controlling individual Dubstep beats or sound effects with the Kinect. Synapse allows you to map multiple effects to each limb, sending joint positions, hit events, and image depth data to both Ableton and Quartz Composer via OSC. The user interface looks fairly easy to work with, enabling musicians and artists to create awesome audio/visual displays using their bodies as instruments, in a very short period of time.

Check out the pair of videos below to see a brief walkthrough of the software interface as well as a quick video demonstration of what Synapse is capable of.

[via KinectHacks]

[Steve Hobley] built a Theremin interface board that tracks pitch and volume. Using this setup he’s able to pass data over a midi interface which effectively converts the instrument into a non-contact midi controller. As we joked in the headline, this does allow for the use of autotune, by snapping notes that are sharp or flat to the center of the nearest pitch. But you should watch the video after the break to see [Steve] show off the other features as well. A keyboard can be used to seed a starting pitch, with arpeggios of several different tonalities built on top of it based on the input from the Theremin.

Want the details? Unfortunately you’ll have to pay for the schematics. But the concept is still just as interesting to read about, even if you don’t know what went into the system.

Oh [Humberto], what will you think up next? A human Theremin you say, and it’s for Halloween? Certanly this will blow last years creepy capacitance sensing jack-o-lantern out of the water right? Eh, not really, but still cool none-the-less. By using pairs of IR LEDs and IR photo-transistors, [Humberto] makes a simplistic distance sensor. Then its just a matter of converting that light value into sound, which is accomplished by using some very clever PWM square wave hacking to make a triangle wave. Also, [Humberto] goes over the process of using fast integers to represent slow floating point numbers. While none of the project is really a new concept, it certainly is put into an easy perspective so anyone can try their hand at it. All well worth the read, or you can catch a video after the jump.

Remember those Ebay auctions of air guitars going for several thousands of dollars? We don’t either, but Theremin Hero (more info in the YouTube description) is about as legit as you can get to actually rocking on nothing but air.

Much like using a theremin to control Mario, the vertical antenna acts as the fret board while the horizontal one detects strumming. Combine the output of the theremin with some custom software (yet to be released) and Guitar Hero and you have Theremin Hero Air Guitar.

[via Bob's House of Video Games]

[Mojo] has taken a lot of the complex circuitry out of the mix by creating a virtual Theremin. A Theremin is an electronic instrument, usually with two antennas, that senses the proximity of the player’s hands to the instrument and responds accordingly.

This design, called the AirDeck, uses a Wii remote as an IR sensor and two gloves with IR LEDs in them. Data from the Wii remote is processed by a custom Java app that converts it into sound. [Mojo's] interface also includes some alternative options such as a turn-table scratch interface.

In the end this is still just a synthesizer/midi controller and cannot stand up to the real thing. However if you’re not an accomplished player you’ll probably never notice the difference.

In the video above, [conquerearth] is using a theremin to control Super Mario Bros. Moving his hand toward and away from the vertical antenna increases the theremin’s pitch. The computer monitors this in real time and moves Mario left and right. The loop antenna controls the theremin’s volume and acts as the jump button. The controls seem to work well, much better than the sound of one man flailing at a theremin.

[via Gizmodo]

[vilxes91] sent in this cool little false-theremin (translated). Its a pretty simple circuit, that can fit in really small places. It isn’t a true theremen because it uses the amount of light coming in around the lid for the modulation. To play it, you turn it on and open it up, the more open the lid, the higher the pitch. You can see a video of it in action after the break.

If you like the sound of the theramin, you may enjoy the Ondestrak.  Based loosely off of the Ondes Martnot, the Ondestrak works by changing the pitch of a continuous note. [Devin_mccutchen] built his using an old gametrak controller. The controller looks pretty cool. We hadn’t seen that one before. Check out a more musical performance after the break.

[via Matrixsynth]

It’s construction is relatively simple: an Arduino, several infrared sensors, and LEDs corresponding to the notes make up the device. It doesn’t have any built-in audio hardware at all, so it’s most basic use is as a MIDI controller. Still, it is essentially an unspecified input device, so it could theoretically be used for other purposes. For us, it’s fun to just watch the AirPiano in action.