If you’re anything like us, more than a few of your projects were borne out of the fact that you had some crusty bit of gear that was badly in need of a second lease on life. Whether it was a hand-me-down or pulled out of the garbage, we’ve all at one time or another had some piece of hardware in our hands that might not be worth anything in its current form, but would make an awesome excuse for warming up the soldering iron.
That’s what happened when [joekutz] got his hands on this exceptionally juvenile keyboard toy. In its original state, it was so janky it couldn’t even reliably detect two keys being pressed at the same time; sort of a problem for a keyboard. So he decided to pull it apart and use it as a circuit bending playground. Thanks in part to how much free space was inside of the case, he was able to pack in a number of interesting modifications which he’s kindly detailed on Hackaday.io.
[joekutz] started by adding a headphone jack to the device, as well as a switch to disable the keyboard’s speaker. That allows not only listening to digital jams in private, but makes it possible to capture high-quality audio when connected to the computer. He then started poking around the PCB with a resistor and listening for changes. When the pitch of the keyboard changed, he soldered a potentiometer into its place and now had a way to adjust it on the fly.
Of particular note is the clever physical reverb he came up with. A microphone and speaker are connected to each other with a spring made out of an old guitar string. Audio from the keyboard’s PCB is played on the speaker and a TDA2022 low-voltage amplifier boosts the signal from the microphone. The end result is a very cool ethereal metallic effect.
Circuit bending is the art of creatively short circuiting low voltage hardware to create interesting and unexpected results. It’s generally applied to things like Furbys, old Casio keyboards, or early consoles to create audio and video glitches for artistic effect. It’s often practiced with a random approach, but by bringing in a little knowledge, you can get astounding results. [r20029] decided to apply her knowledge of CD players and RAM to create this glitched out Sony Discman.
Circuit-bending is tons of fun. The basic idea is that you take parts of any old electronic device, say a cheap toy keyboard, and probe all around with wires and resistors, disturbing its normal functioning and hoping to get something cool. And then you make art or music or whatever out of it. But that’s a lot of work. What you really need is a circuit-bending robot!
Circuit bending is the process of taking a small electronic toy or musical instrument, soldering wires to pads on the PCB, and hoping the sounds it produces will be cool. It’s not a science by any means, and any good, weird sounds you’ll get out of a Speak ‘N Spell or old MIDI keyboard are made entirely by accident or hours and hours of experimentation.
Until now, you could tell how technically adept a circuit bender was simply by how many switches were on the circuit-bent instrument. [Alpha Charlie] doesn’t need switches. Instead, he’s using a few crosspoint switch ICs to connect different pins and pads on the TR-626’s PCB with an Arduino. All of this is controlled by a touchscreen display, and experimenting with the circuit is as simple as pushing a few buttons. Each ‘bend’ is computer controlled, and can be saved and recalled at will.
Of course, circuit bending doesn’t do anyone any good if it sounds like crap. [Alpha Charlie] doesn’t have to worry there. In the video below, he’s getting some very unique sounds that sound like a choir of angels to dorks like myself that listen to Nintendo music.
We have often commented that we’re a bit tired of hearing random notes when someone sends us a musical project. We love home made instruments, circuit bending, and creative sound, we just like some intentional direction to the noise. This just might be an exception to the rule. This typewriter plays random notes as you type. While it might annoy your cohabitants into a violent rage, it seems oddly cathartic. We have heard people talk about the pleasure of hearing the keys clack as they type. It just seems like you would get used to this and find it just as pleasurable. Maybe we’re crazy. Unfortunately, they don’t divulge any technical details, but we can imagine a simple way of wiring directly into a cheap keyboard to get the same effect.
This is an interesting instrument. Part laser harp, part guitar, the Prism seems to have some potential. [Jeff-o] put some major time and effort into refinishing a guitar, building the circuit and putting it all together. He did a great job, the instrument looks fantastic and appears to work. We do have a request though; please post a video of it being played as an instrument. So many of these electronic instrument projects just spit out random noises. While we understand that some people are into that, we would love to hear some control. How about intentionally changing notes to make a melody? Based on the description, it should have control for pitch, and even speed of the oscillation. So let’s hear some music. We don’t care if you’re any good, just please play some music with it. If you would like to build your own, he has the schematics and PCB layout available for download.