Cheap 80s Keyboard Gets Modern Brain Upgrade

The 1981 Casio VL-1 was a fine cheap keyboard. It had a robust build, though an admittedly limited sound palette. [Max Vega] had one of these charming instruments, and decided to use modern tech to rebrain it for the modern world.

The original electronics of the VL-1 were largely surplus to requirements for this build. The original interface and speaker were kept in service, while the rest of the monophonic sound synthesis hardware was removed. [Max Vega] enlisted an ESP32-C3 to run the show, turning the VL-1 into a ROMpler instead. If you’re unfamiliar with the term, it refers to a keyboard or other instrument that relies on hardcoded sample playback instead of raw synthesis. The ESP32 loads its samples from a microSD card, which provides an enormous amount of storage for different sound packs. Selecting different instruments is handled with a simple interface built around the original buttons and a OLED screen.  Playing the instrument is still the same using the simple keyboard, though [Max] also implemented some extra fun modes that play chords at a single touch.

If you want a fun, versatile keyboard instrument that fits perfectly in a backpack, it’s hard to go wrong with a build like this. We’ve seen similar Casio keyboard hacks before, too. Video after the break.

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New Record Resurrects Long-Dead CD Graphics Format

Audio CDs were the ubiquitous audio format of the 1990s. Lesser known were the extensions to the format that packaged all kinds of interesting additional data into a musical release. Now, a new record from [Aizysse Baga] has brought back some of the most quirky and obscure CD features that time and industry long forgot.

[Aizysse Baga] worked with [Adelaide] on the Divacore record, which was to be released on a mini-CD. The original plan was to include additional CD+G data, featuring artwork to go with the music. CD+G, or CD+Graphics, was often used to display synchronized lyrics for karaoke releases, and stored data in formerly-unused subcodes next to the track start, track number, and running time data. This format allowed storing a slideshow of images with a resolution of 288 x 192 with a 16 color palette.

Note the quality difference between the 16-color CD+G and the 256-color CD+EG images.

The duo got handy with art and some smart dithering to get great 16-bit artwork packed in to the audio CD release, with the aid of a custom Python encoder. CD-TEXT metadata was thrown in for good measure. Then, the existence of the more advanced CD+EG became apparent. This was a 256-color extension to the CD+G format that was backwards compatible to boot. It was a format that was barely ever implemented on any commercial releases, and very little hardware could even display it. Naturally, Divacore had to have it. Much work was done to understand the Red Book documentation on the standard and figure out how to implement even higher quality artwork for the record.

After so much work to understand and implement the CD+G and CD+EG data, the question was whether it would survive the CD reproduction process for the final release. Thankfully, the final discs came out perfectly, and the full 256-color CD+EG artwork can be seen in all its glory if you happen to play Divacore on a Sega Saturn or a super-obscure Victor VS-G2 or VS-G3. Throw it in a less-sophisticated karaoke machine or something like an Amiga CD32, and you’ll still get to see the 16-color versions for your trouble.

We love to see ancient formats brought back to life, particularly those that never got their time in the sun. If you’re working hard to resurrect something the mainstream media world has forgotten, let us know on the tipsline.

A Commodore Boombox: The 1530 As You’ve Never Heard It Before

No, this isn’t another product from [PeriFractic]’s revived company, though we hope he’s taking notes. This is, in fact, a hack on the beloved 1530 Datasette, using the tape mechanism and case to create a portable audio device for your precious remaining mix tapes. Well, [Jan Derogee]’s precious mix tapes, at any rate; we aren’t the government, we don’t know if you have any tapes, mixed or otherwise.

[Jan] started, obviously enough, with a Datasette, but they key was apparently to use a Made-in-Japan model–  the Made-in-Taiwan units are a later development and victims of the old Commodore’s infamous obsession with cost-cutting. The main difference is that the Japanese-built Datasettes have two sets of screws: one to hold the tape mechanism in place, and the other to hold two halves of the case together. The Taiwanese units make one set do double duty. Doubtless more was saved through streamlining assembly than the cost of four screws, but either way it made those models difficult to work with for [Jan]’s purposes.

As you likely can tell from the photo, he simply splits the case, allowing the tape transport to remain in place with those  Japanese screws, and inserts a 3D printed spacer to hold speakers, audio amplifiers, and a bay for AA batteries. For the people who really care about such things, the mod appears to be fully reversible, though you won’t be able to use it as data entry for your C64 until you do reverse it. Given how slow and dodgy tape loads could be, though, that’s not likely to bother many people, since it’s so much easier to load media onto the old breadbox from an emulated tapedeck.

If, on the other hand, you can’t stand the idea of using a Datasette for anything but data storage, maybe you should try connecting yours to a modern PC to remind yourself what it was really like. In either case, you can check out the 1530 Boombox at the link above or the video embedded below. For the actual Commodore product we didn’t see coming, click here for the phone. 

Leaky Player Piano Gets MIDI Upgrade In YouTube Restomod

The word “restomod” is a bit nebulous, but it’s normally used in the automotive world to describe taking an old car and making it better-than-new with all the technological improvements the original builders would have used, had they been available. We think the word applies to [Alnwlsn]’s MIDI-actuated player piano, because what are those punched rolls of paper, but the MIDI of the 19th century?

Unlike a lot of automotive restomods though, this one is mostly reversible. He did drill few holes and slots in the original wood, but nowhere that it would alter the integrity or original operation of the player piano mechanism. The MIDI-controlled solenoids just poke the same key paddles from below that the pneumatic mechanism used. From the listener or operator’s perspective, unless the doors that reveal the music scroll or lack thereof are open, the piano behaves exactly the same. Except now it has access to the whole wide array of tracks that exist in MIDI form, rather than a paltry selection of hard-to-find piano rolls.

Each of the relays is driven by a MOSFET via shift registers to get 88 outputs out of the single Pi Pico in charge, with a level shifter involved to get the RP2040 speaking 5 V logic. If you’re wondering how that gets volume control, no, the piano isn’t smacking keys at full volume all the time. He’s using the RP2040’s powerful PIO to create a sort of PWM signal to soften the solenoid blows when needed. To save his power supply, he’s also got it set up to stagger the pulses, so multiple relays aren’t pulsed at the same time when the MIDI file calls for chords.

There was actually more overlap between player pianos and MIDI than you might think, given this presentation of an Apple ][ being used to create the piano rolls.

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Pico-Driven Ultrasound Enables Scaled Acoustic Model Of Home Stereo

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!

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Bluetooth Gramophone Has Surprisingly Contemporary Roots

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”

The turntable in question, or at least the same model.

Vintage Turntable Gets Brain Transplant And Home Assistant Integration

When [Marsupial] picked up a vintage Sansusi P-L45 turntable, he figured it would be an easy fix: a few capacitors, a belt or two, and maybe a new cartridge, the usual. But it turned out the electronics were fried, which set the stage for an upgrade that turned it into what may be the world’s only ESP32-driven, Home Assistant integrated, linear tracking turntable.

That last bit, the linear tracking, is why the turntable originally had a microprocessor in the first place: rather than an arm that pivots along the groove naturally, fancy turntables towards the end of the golden era of vinyl slid the needle along a linear track at a variable speed to follow the spiral groove on the record. You can see that in action in the demo video below, though it’s of a working version owned by [BFinks].

The fancy linear mechanism required electronic control to match the speed to the RPM, and in the example of Sansusi’s P-L45, that was provided by an NEC microcontroller on a daughter-board labelled “F4992 CPU”. CPU is a grandiose title, perhaps, but that’s irrelevant since the chip on the board was deader than disco.

That meant [Marsupial] had some reverse engineering to do — figuring out exactly what that chip did to drive this board, in order to replicate its behavior on an ESP32-S3. Luckily the golden era of vinyl correlated with the golden era of service manuals, and the manuals are still available, so [Marsupial] had a big leg up on that. After making the turntable work like stock, what else to do with the extra capability of the ESP32 than plug it into HA and make it really automatic?

Of course it wasn’t quite that easy: a new daughter-board was created that needed to do level shifting to the ESP32’s modern 3.3 V logic as well as hardware debounce on some inputs. The whole saga is very well documented on [Marsupial]’s blog WeAreAllGeeks. The link here takes you to the overview, but he’s got a lot more info on other pages — and of course links to the firmware and PCB design if you happen to have a Sansusi turntable in need of a brain transplant.

Vinyl lovers will appreciate this project much more than the last ESP32 “turntable” we featured, which was anything but. If you want to get into records but don’t have a turntable, you can always make your own.

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