Musical Hacks

1470 Articles

A Childhood Dream, Created And Open Sourced

October 7, 2025 by 12 Comments

Some kids dream about getting a pony, others dream about a small form factor violin-style MIDI controller. [Brady Y. Lin] was one of the latter, and now, with the skills he’s learning at Northwestern, he can make that dream a reality — and share it with all of us as an open source hardware project.

The dream instrument’s name is Stradex1, and it’s a lovely bit of kit. The “fretless” neck is a SoftPot linear potentiometer being sampled by an ADS1115 ADC — that’s a 16-bit unit, so while one might pedantically argue that there are discreet frets, there’s 2^15 of them, which is functionally the same as none at all. Certainly it’s enough resolution for continuous-sounding pitch control, as well as vibrato, as you can see at 3:20 in the demo video below. The four buttons that correspond to the four strings of a violin aren’t just push-buttons, but also contain force sensors (again, sampled by the 16-bit ADC) to allow for fine volume control of each tone.

A few other potentiometers flesh out the build, allowing control over different MIDI parameters, such as what key [Brady] is playing on. The body is a combination of 3D printed plastic and laser-cut acrylic, but [Brady] suggests you could also print the front and back panels if you don’t happen to have a laser cutter handy.

This project sounds great, and it satisfies the maker’s inner child, so what’s not to love. We’ve had lots of MIDI controllers on Hackaday over the years — everything from stringless guitars  to wheel-less Hurdy-Gurdies to say nothing of laser harps galore — but somehow, we’ve never had a MIDI violin. The violin hacks we have featured tend to be either 3D printed or comically small.

If you like this project but don’t feel like fabbing and populating the PCB, [Brady] is going to be giving one away to his 1000th YouTube subscriber. As of this writing, he’s only got 800, so that could be you!

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GuitarPie Uses Guitar As Interface, No Raspberries Needed

October 6, 2025 by 14 Comments

We’ve covered plenty of interesting human input devices over the years, but how about an instrument? No, not as a MIDI controller, but to interact with what’s going on-on screen. That’s the job of GuitarPie, a guitar-driven pie menu produced by a group at the University of Stuttgart.

The idea is pretty simple: the computer is listening for one specific note, which cues the pie menu on screen. Options on the pie menu can be selected by playing notes on adjacent strings and frets. (Check it out in action in the video embedded below). This is obviously best for guitar players, and has been built into a tablature program they’re calling TabCTRL. For those not in the loop, tablature, also known as tabs, is an instrument-specific notation system for stringed instruments that’s quite popular with guitar players. So TabCTRL is a music-learning program, that shows how to play a given song.

With this pairing, you can rock out to the tablature, the guitarist need never take their hands off the frets. You might be wondering “how isn’t the menu triggered during regular play”? Well, the boffins at Stuttgart thought of that– in TabCTRL, the menu is locked out while play mode is active. (It keeps track of tempo for you, too, highlighting the current musical phrase.) A moment’s silence (say, after you made a mistake and want to restart the song) stops play mode and you can then activate the menu. It’s well a well-thought-out UI. It’s also open source, with all the code going up on GitHub by the end of October.

The neat thing is that this is pure software; it will work with any unmodified guitar and computer. You only need a microphone in front of the amp to pick up the notes. One could, of course, use voice control– we’ve seen no shortage of hacks with that–but that’s decidedly less fun. Purists can comfort themselves that at least this time the computer interface is a real guitar, and not a guitar-shaped MIDI controller. Continue reading “GuitarPie Uses Guitar As Interface, No Raspberries Needed” →

How Your SID May Not Be As Tuneful As You’d Like

October 4, 2025 by 6 Comments

The MOS Technologies 6581, or SID, is perhaps the integrated circuit whose sound is most sought-after in the chiptune world. Its three voices and mix of waveforms define so much of our collective memories of 1980s computing culture, so it’s no surprise that modern musicians seek out SID synthesisers of their own. One of these is the MIDISID, produced by [MIDI IN],  and in a recent video she investigates an unexpected tuning problem.

It started when she received customer reports of SIDs that were out of tune, and in the video she delves deeply into the subject. The original SID gained its timing from a clock signal provided by the Commodore 64, with thus different timing between NTSC and PAL versions of the machine. This meant European SID music needed different software values to American compositions, and along the way she reveals a localisation error in that the British Commodore 64 manual had the wrong table of values.

Modern SIDs are emulated unless you happen to have an original, and her problem came when switching from one emulated SID to another. The first one used that clock pin while the second has its own clock, resulting in some music being off-tune. It’s a straightforward firmware fix for her, but an interesting dive into how these chips worked for the rest of us.

Continue reading “How Your SID May Not Be As Tuneful As You’d Like” →

A photo of the front-panel with a bunch of lamps and knobs.

The Making Of A Minimalist Analog Drum Machine

October 1, 2025 by 14 Comments

Our hacker [Moritz Klein] shows us how to make a minimalist analog drum machine. If you want the gory details check out the video embedded below and there is a first class write-up available as a 78 page PDF manual too. Indeed it has been a while since we have seen a project which was this well documented.

A typical drum machine will have many buttons and LEDs and is usually implemented with a microcontroller. In this project [Moritz] eschews that complexity and comes up with an analog solution using a few integrated circuits, LEDs, and buttons.

The heart of the build are the integrated circuits which include two TL074 quad op amps, a TL072 dual op amp, a CD4520 binary counter, and eight CD4015 shift registers. Fifteen switches and buttons are used along with seven LEDs. And speaking of LEDs, our hacker [Moritz] seems to have an LED schematic symbol tattooed to his hand, and we don’t know about you, but this screams credibility to us! :)

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NTRON Plays Games, Music

September 28, 2025 by 7 Comments

What do you get if you meld a Raspberry Pi, a chiptune synthesizer, and a case that looks like an imaginary Kenback-2000? Well, if you are [Artifextron], you get the NTRON. Part Nintendo console, part chip tune synthesizer, and part objet d’art. You can see the device do its things in the video below.

This is less of a bare metal design and more of a synthesis of parts, but it is a very clever system design using audio mixers and an assortment of modules to do its tasks. It does have an IC handling the gamepad ports. Of course, it also features a ton of 3D printed parts.

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Bringing Bluetooth To The Zune

September 27, 2025 by 10 Comments

The Zune might have joined the portable media player game too late to ever really be competition for the iPod, but that doesn’t mean it didn’t pick up some devoted fans along the way. Some of them are still breathing new life into the device, such as [The Director of Legal Evil Emeritus] at the Louisville Hackerspace, with this project that gives it Bluetooth capability.

As far as media players go, there’s still some solid reasons to rock a Zune. Compared to other devices of the era, it offers a better DAC, an FM tuner, and no iTunes reliance. The goal of this project was to bring a bit of modern functionality without having to do any modification of the Zune itself. As the player supported docks with IR remotes, this build involves using an ESP32 to listen to the Bluetooth signal coming from the speakers, interpret any button presses, and forward them along to the Zune’s dock.

There is a dedicated scene for these old music players, but this build is unique for not needing to crack open the case and splice in a Bluetooth module. Even then, those typically don’t have the ability to interact with things like this speaker with its integrated control buttons.

We don’t often seen Zune hacks come our way — the last time Microsoft’s player graced these pages was in 2010, when the Open Zune Development Kit was released.

Thanks to [JAC_101] for the tip!

March To The Beat Of Your Own Piezoelectric Drum

September 20, 2025 by 7 Comments

Drums! You hit them, and they vibrate. It’s kind of fun. Piezoelectric elements can create electric current when they vibrate. [Will Dana] put two and two together to try and charge his phone on his YouTube channel WillsBuilds embedded below.

It worked… about as well as you might expect. Which is to say: not very well. The random piezo elements [Will] glues to his drum almost certainly aren’t optimized for this use case. Adding weight helps, but it doesn’t look like a tuned system. Even if it was, piezoelectric generators aren’t terribly efficient by nature, and the (small) losses from the required bridge rectifiers aren’t helping. An energy-harvesting chip might have worked better, but it probably wouldn’t have worked well.

Since he cannot produce enough voltage in real time, [Will] opts to charge a capacitor bank that he can dump into the phone once it gets enough charge in it to register with the phone’s circuitry. It takes about 30 minutes drumming to charge the capacitors in parallel, before switching to series to get the voltage up to discharge. The capacitors drain in about a quarter second, probably to no measurable result– but the phone does read as “charging”, which was the goal.

Did it work? Technically, yes. The phone was “charging”. Is it practical? Certainly not. Is it a hack? Undeniably so.

Continue reading “March To The Beat Of Your Own Piezoelectric Drum” →