How it works

A 3D printer (tested on a Bambu Lab P1S with a 0.4 mm nozzle), PLA, and a turntable that can spin 45 or 78 rpm. An inexpensive cartridge with a replaceable stylus, never your good one. That is the whole shopping list.

We do not know your printer's start-up routine: bed levelling, purge line, temperatures. So you hand us one file that contains it. In Bambu Studio, drop in any small object, ideally a 10 mm cube, and slice it with your normal profile (P1S, 0.4 mm nozzle, PLA, 0.2 mm layers, your build plate), then choose Export → Export plate sliced file. Save it as template.gcode.3mf and drop it on the site. We take only the first and last block of that file. Everything between is written by the engine.

Start with a test melody. It is a public-domain tune we synthesise on the spot, so you can print without uploading anything. Once that plays, switch to your own music: drop an mp3, click the waveform to choose the passage, and the engine cuts it to whatever the disc holds.

Download the .gcode.3mf and open it in Bambu Studio (File → Import), or send it straight to the printer. Watch the first layer. If the base looks patchy, stop and check your bed adhesion before you spend three hours.

Put the disc on the platter, set the speed the site shows, tracking force about 2 g, anti-skate 2. Lower the needle with the cueing lever onto the wide run-in groove at the edge. If the stylus skates across the surface instead of tracking, lift it immediately and tell us. That is a groove-shape problem we can fix in the settings.

Print the tuning record, play it while recording over USB, and upload the recording. The engine measures what your specific turntable and cartridge actually deliver at each radius, and corrects every later record for it.

• This is a lo-fi novelty, not hi-fi. The bandwidth ends somewhere between 250 and 1000 Hz depending on speed and radius, so you get melody and voice, not cymbals and bass.
• There is audible surface noise. A 0.4 mm extrusion is roughly ten times coarser than a cut groove.
• A 250 mm disc holds about 27 seconds at 78 rpm or 47 seconds at 45 rpm. That is physics, not a software limit.
• Only the Bambu P1S has been tested end to end. Other printers may work. Check the preview and watch the first layer.