December 4, 2025
Spinny orbs, spicier comments
Multivox: Volumetric Display
DIY 3D orb wows, then physics and hot takes crash the party
TLDR: Open-source Multivox lets you build a spinning 3D LED orb with demos and printable parts, and there’s a video. The comments cheer the DIY magic while debating physics limits, non-spinning glass alternatives, and whether a big company should boost resolution—even if it hikes the price.
Multivox turns two spinning LED panels into a mesmerizing 3D “orb” you can walk around, powered by a humble Raspberry Pi and packed with arcade‑style demos. There are two flavors—Rotovox (taller, denser) and Vortex (brighter, faster)—with open code, printable parts, and even a simulator. The community immediately rushes in with awe… and a reality check. JKCalhoun drops the video and warns that true “holograms” this ain’t: since the orb can’t hide the back of objects, cutaways look best, sparking a chorus of “physics says hi.” Then thesz escalates with a rival glass‑etching display that doesn’t spin at all, igniting the “rotating gizmo vs. crystal sci‑fi” debate. dllu confesses they nearly built a lidar point‑cloud orb but “was too lazy,” instantly becoming the thread’s mood meme. Meanwhile tra3 is starstruck by the skill mashup—software, math, 3D printing, electronics—calling it “incredible.” And qoez chimes in with a spicy wish: let a mega‑company swoop in to jack up resolution… and the price. The vibe: DIY wizardry meets reality‑check theater. Yes, it spins at hundreds of RPM and syncs with a tiny sensor; yes, it’s dazzling; and yes, the comments are even brighter than the LEDs.
Key Points
- •Multivox is an open-source codebase for spinning HUB75 LED volumetric displays on Raspberry Pi 4.
- •It supports two devices: Rotovox (vertical panel layout, higher vertical resolution) and Vortex (horizontal layout, brighter with higher refresh).
- •Hardware uses a single GPIO sensor to sync rotation and relies on memory-mapped GPIO; BCM_BASE must change for non–Pi 4 models.
- •Software architecture includes a shared-memory voxel buffer, a driver, client generators, a simulator (X11), and multiple volumetric demos.
- •Build with CMake and run the driver (`sudo ./vortex`); the driver provides profiling and keyboard controls, including bit-depth cycling.