Author: Tyler August

559 Articles

Pico-Driven Ultrasound Enables Scaled Acoustic Model Of Home Stereo

June 8, 2026 by 2 Comments

There are plenty of ways to get sound into your house: good old fashioned headphones, the Dolby surround setup we all lusted after back in the day, or the 21st century’s ubiquitous soundbar, with its ‘spatial audio’ magic. Which will work in your space? If you were an audio engineer, you’d set up listening area and use a microphone to map the space– but that would be thousands of points and sounds like tedium. [PlasmatronX] had a better idea: use Schlieren imaging to see the sound waves as the travel through the space. Schlieren imaging has trouble with audio frequencies, though, and imaging the entire living room was going to be difficult. So he scaled it all down– including the sound waves, by shifting to ultrasonic frequencies.

He’s using the usual mirror-and-razor Schlieren setup with an 8″ telescope mirror– and if you don’t know what that is, we did a deep dive on this kind of optical flow visualizer a while back. Inside the circular imaging area where that lets him see density changes, he’s set up what he calls a CAT– Computer Acoustic Tomography– array. It’s a rig on a turntable he can set up ultrasonic transducers on, to match the various speaker setups he wants to test, and turn so he can see from all angles what the scaled-down waves are doing. To capture those waves, which aren’t going to be standing still, he adds a stroboscope. All the ultrasound signals are being generated by a Pi Pico, and are scaled 4:1 in the frequency domain– that is, a high 10kHz whine becomes inaudible 40kHz. Those signals are fed through a DIY 8-channel amp into both ultrasonic transducers and larger ‘cat-repellent speakers’ from AliExpress.

The microcontroller is actually a Pico 2W, which is using its “W” to communicate via Bluetooth with a Pi 4. That SBC is running the camera, the stepper for the turntable, and image processing, along with the timing for the audio signals. After that it’s a matter of setting up a scaled down 7.1 surround setup and itty-bity soundbar, and test it on a (stuffed) guinea pig. Obviously you can see a big difference between the steered beams from the tiny soundbar and the true surround, but how that translates to listening pleasure will be at least somewhat subjective.

What’s less subjective is the obvious effect soft furnishings add to the simulation. Now he doesn’t take the time to find a material that will scale the frequency response of a set of curtains, but we’re not sure how much that matters. At 5kHz or 20kHz, they’re going to deaden sound, and you can see that here, and you can see it’s a much bigger deal for the shaped beams of the soundbar than it is for surround sound. In the end, [PlasmatronX] decides to stick to headphones, but the whole video is very much worth watching, so we’ve embeddded it below. If you want to try it yourself he’s put his code on GitHub.

Thanks to [PlasmatronX] for the tip!

Continue reading “Pico-Driven Ultrasound Enables Scaled Acoustic Model Of Home Stereo” →

Bluetooth Gramophone Has Surprisingly Contemporary Roots

June 7, 2026 by 17 Comments

So you happen to have a gramaphone– maybe a big old Victrola/HMV, perhaps a Columbia– regardless of brand, it’s a big, beautiful conversation peice for your living room. It might not be the most practical listening device, since isnomuch as there is a vinyl renessance, it’s restricted to vinyl, not the old shellac 78s the these all-mechanical beasts were born for. [JGJMatt] decided to bring his gramophone into the 21st century, turning it into a bluetooth speaker without altering any of its original internals.

What’s really interesting is that this hack was once a commercial product– sort of. Back in the 1920s when everyone was listening to Jazz, the problem of ‘ what do I do with this massive gramophone cabinet when I’m not cutting a rug?’ was equally valid, and a solution was found: the Dulce-Tone Radio Speaker. A very weak speaker sits under the needle, turning the gramaphone mechanism into an amplifier for the radio. The very same concept, [JGJMatt] would work equally well in the 2020s with a bluetooth signal as in the 1920s with an AM one. There’s no demo video for this project, but you can hear how its 1920s inspiration sounded in the video below.

The driver for this device is made using a neodymium magnet and the voice coil from a 3W speaker. A 3D-printed needle-holder captures the gramophone’s needle– a much thicker and sturdier thing than the tiny diamond-tip you’d find on a modern turntable, we should note– and holds the magnet to it. The voice coil gets driven via a MH-M38 bluetooth module, and everything is held in a nice 3D-printed case along with the battery.

The hack is, of course, totally reversible: at any moment, you can remove the needle from this device and drop it on a 78 for some Jazz-era fun, or swap back for 21st century brainrot. If you happen to have some of those old shellac records and a modern turntable, note it takes more than the right RPM to get good sound. Continue reading “Bluetooth Gramophone Has Surprisingly Contemporary Roots” →

LIPS Is An Open Source Sip-And-Puff Interface

June 7, 2026 by 5 Comments

Lots of us have– thanks to repetative stress injuries– developed mobility issues that we have to work around when using computers. Maybe it’s a trackball instead of a mouse, or a split keyboard, or mechanical keys with very specific force requirements– but those are small potatoes compared to people with such severe movement issues such as quadriplegia who need to fall back on things like a sip-and-puff device to control the computer with their mouths. Commercial options of course come with absurd price tags, but a DIY option is a different story. [DanielYordanov]’s L.I.P.S project can be built for only a couple percent of what the big boys want, and it’s fully-open source.

So you might think a sip-and-puff device is a two-bit interface, only slightly more advanced than the morse terminal we featured earlier. While Morse code might be an option, these devices also act as pointers, as the lips and chin can be used to point the mouthpiece. Thus there are a few sensors needed: a hall-effect joystick for pointing info, and one or more pressure sensors to detect the breathing interface for ‘clicks’. [Daniel] has single and dual-sensor versions, creating at minimum a four-button mouse. In reality this hardware can distinguish long and short pulses, or combinations of breath to run some nice macros. With operating-system features like an on-screen keyboard, L.I.P.S. can provide someone with digital freedom– and at a tiny fraction of the cost of a ‘real’ medical device.

Despite the DIY nature, for the end-user control and config is easy enough thanks to a webserial portal run on the CH552 that you can preview on the official website. Code, ki-cad and STL files are all on his GitHub repository. If you’re interested in the design process, we’ve embedded his video about that below.

Thanks to [Daniel] for the tip! Do you know of a hack to make life better for someone, disabled or otherwise? Send us a tip!

From one-handed typing to open-source prosthesis, this sort quality-of-life hack may be the best thing about our community. Continue reading “LIPS Is An Open Source Sip-And-Puff Interface” →

Apparently what a fusion power plant should look like

Less Than 10 Years? Commonwealth Fusion Systems Applies To Plug Into Grid In 2030s

June 7, 2026 by 58 Comments

Whenever the topic of fusion power comes up, someone will say it’s only 10 years away from commercialization in an excited tone, and someone older or more cynical will point out that it’s been 10 years away since Eisenhower was president. So it’s with a certain-sized crystal of sodium chloride that we share the news here that the US-based Commonwealth Fusion Systems is applying to feed 400MWe into the grid there by the early 2030s.

The early 2030s is, notably, less than ten years from now.

Commonwealth Fusion Systems isn’t a bunch of nobodies out to suck up venture capital; they’re a talented group of researchers from MIT’s well-known plasma laboratory out to suck up lots of venture capital and hopefully build reactors along the way. So far, the second part is going better than the first: they’ve raised a couple billion dollars, which has let them make great strides in building their SPARC reactor– like crafting the big magnet we told you about in 2021. As that article describes, SPARC is the precursor to the later, larger ARC reactor they hope to hook to the grid in slightly under a decade. Alas, SPARC remains under construction as of this writing. ARC is evidently in the final planning stages, with a physical location determined and grid-tie applied for at the “Fall Line Fusion Power Station” in Virginia.

CFS’s reactors are of the Tokamak type that has been favoured at universities since the 1970s. From China to Europe’s ITER who are also planning to produce power before another decade passes— though not, notably, into a power grid. While promising, Tokamaks aren’t the only game in town, either– steampunk startup General Fusion started making plasma last year, though while if it works it has some big advantages, that one is probably the traditional “ten years away” still.

What do you think? Will fusion power be in the grid before humans make it back to the moon? Add the flying-car potential of eVTOL and we might finally get close to the future we were promised.

A RayCast FPS In COBOL

June 6, 2026 by 5 Comments

COBOL is not the first language anyone would ever think of when writing a First Person Shooter– after all , it’s the Common Business Oriented Language, not the Common Game Oriented Language. For Youtube-based hacker [icitry] though, that’s the point. The only way to determine if COBOL would be enough to write an FPS game was to do it.

Sure, you could rest on your laurels knowing that the language is Turing complete and therefore capable by definition, but what’s the fun in that? Now the pipeline for this game is as hacky as anything– COBOL doesn’t exactly have a robust graphics stack or a lot of libraries for pushing pixles, so he’s outputting each frame of the game as raw bitmap to STDOUT, and letting ffplay assemble the images. Control enters the same way, with the terminal set to raw input and the COBOL program reading STDIN.

As for what the images consist of, he’s going for a standard Wolfenstien-inspired raycasting shooter. [icitr] provides a decent explanation of the raycasting algorithm, along with why implementing in COBOL is a silly thing to try. That’s a theme here; he’s able to implement sprites and the logic to move and attack enemies, while constantly complaining about COBOL. If that wasn’t enough, he adds variable-height sectors to bring this much closer to a true DOOM clone. By the end, there’s a full game. It’s all up on GitHub on an Apache license.

While this video is not the most gentle introduction to COBOL, it does show you can hack the business-specific language to do whatever you’d like.

Pi Pico Demos, Therefore It Is

June 6, 2026 by 18 Comments

A good demo, like [Linus Akesson]’s Sum Ergo Demonstrato, looks like magic to the average hacker. To normies who don’t know the limitations of the RP2350, they don’t see the big deal. To anyone who has spent any time with the chip, though, it’s a series of tricks you cannot help but be amazed by. Fortuanately for us, [Linus] isn’t actually a magician, because while a magician never reveals his tricks, [Linus] has an hour-long video explaining exactly how his demo was accomplished. We’ve embedded both the demo and the explanation below.

Even if you aren’t into YouTube, you should check out the demo video, and again– remember this is all on a Pi Pico with only the extra passives required for video-out. Then you can watch [Linus] explain how he did it, which is really best heard in his own words. There are a couple of bleeding-edge tricks on the RISC V core and peripherals that we would hate to misrepresent– especially the clever hack with the interpolator that he uses for 3D acceleration.

If this sounds a bit familiar, it’s because we were equally impressed by his Kaleidoscopico demo last year. From demos like this to 3D engines on the ESP32, its amazing what you can do on modern micros if you’re willing to hit the limits of the hardware.

Thanks to [Stephen Walters] for the tip!

Continue reading “Pi Pico Demos, Therefore It Is” →

As It Turns Out, There’s More Than One Cassette Mechanism Being Made After All

June 5, 2026 by 8 Comments

It’s become an accepted truth amongst tapeheads that there’s no point looking at new hardware, because there’s only one tape mechanism being made anywhere in the world anymore, and that it sucks. [VWestlife] may enjoy German automobiles, based on the name, but he’s also a tapehead– and he took the time to demonstrate on YouTube that the accepted truth just ain’t so.

The supposed One Mechanism to Rule Them All in Lo-Fi is designed or made by Chinese company Tanishin. Certainly Tanishin does make a tape mechanism, but as [VWestlife] demonstrates with a few teardowns, there’s absolutely more than one on the market. That doesn’t mean any of the new offerings will out-compete your vintage Sony Walkman, but it does mean there are differences worth considering if you were to buy new.

Note that it is handhelds like the Walkman being talked about– it must be, since there are both slot-loading and flip-loading decks still being made, and even if you’re not a tapehead you should be able to tell that those won’t share the same part on the BOM.

With a few teardowns, he finds three separate mechanisms, followed by a deep-dive into the Tanishin. If you’re looking to buy a new walkman– or perhaps use its guts to build a mass storage device-– you might want to watch the whole thing to help you pick. On the other hand, the mechanism doesn’t matter that much, as he points out. It brings the tape over the head, but that’s not difficult. Everything else– from the motor that needs to draw the tape out evenly, to the pickup and the preamps and amplifiers–is where noise and poor quality sound tends to creep in, especially when something’s built to a budget.

Overall, [VWestlife] takes pains to point out that these ‘crappy’ new players aren’t any worse than the original Sony Walkman– we’ve just been spoiled by decades of better media than the humble compact cassette. That’s no slight against the cassette– people are still pushing its limits to this day, like this insanely fast vacuum-driven mechanism we featured.

Thanks to [Stephen Walters] for the tip!

Continue reading “As It Turns Out, There’s More Than One Cassette Mechanism Being Made After All” →