No streaming. No subscriptions. No cloud. No AI bullshit. A desktop player obsessed with
how your music sounds and how it looks.
Own your library again.
Native. Not a Browser in Disguise.
Cassette isn't a web page bolted into a window. It's a true native desktop application, compiled to run directly on your machine. No Electron, no Chromium tax, no half-gigabyte of RAM just to sit idle in your tray.
That's why it feels instant. The interface renders at 165+ frames per second, scrolling is glass-smooth, and heavy work like waveform rendering, BPM analysis and key detection runs on background threads so playback never stutters. Not for a single frame. It starts fast, stays light, and gets out of your way.
Real-Time Analysis
A 128-band spectrum analyzer driven by a 4096-sample FFT with Blackman-Harris windowing. The same math pro audio tools use. Buttery attack and release smoothing, redrawing at 165+ frames per second. Most players give you a toy. This is an instrument.
Watch the low end breathe, catch a harsh resonance in the mids, see exactly where a track lives in the spectrum. Whether you're EQ-matching a playlist, checking a master, or just mesmerised by your favourite record, it's all there in real time. Accurate, responsive, and genuinely beautiful.
Stereo Scope
A live goniometer plots every sample pair as a mid/side dot cloud, so you can see at a glance whether a track is mono-compatible, wide, or phase-reversed. The correlation bar below reads from −1 (total cancellation) to +1 (perfect mono). Catch problem mixes before they hit a mono speaker.
When the cloud collapses to a vertical line, you're listening to pure mono. When it fans sideways, the stereo image is breathing. Most players hide all of this. Cassette puts it right in front of you.
Waveform
Every waveform is rendered with our own dual-layer peak & RMS analysis. The loud transients and the quiet body drawn separately, so the structure of the track reads at a glance. Intros, breakdowns, drops and outros become visually distinguishable before you ever press play.
Then grab it and spin. Real jog-wheel scrubbing with inertia physics that feels like vinyl, and scroll to zoom right down to the individual sample. Find the exact beat every time. You'll see the drop coming before it hits.
Video Playback
Music videos. Concert films. Live sets in 4K. Cassette plays it all natively, with multiple audio tracks and embedded or external subtitles you can switch on the fly. Commentary, dubs, alternate mixes, foreign-language subs, whatever the file carries.
One library for your whole collection. Audio and video side by side, organised the same way, played by the same engine. No second app, no juggling windows.
Plays virtually everything you'll throw at it
Mini Player
Shrink Cassette into a compact always-on-top mini player that floats above your other windows. It works for both audio and video. Keep a track spinning while you work, or pin a music video to the corner of your screen.
Full transport controls, live progress, and artwork in a footprint small enough to forget it's there until you need it. Producers: pin a reference track in the mini player while you work in your DAW and A/B your mix against the real thing without ever losing focus.
BPM & Key Detection
BPM and Camelot key detection that runs 100% offline. Bundled analysis engines, zero internet, zero API fees, nothing leaving your machine. Right-click any track, analyze, done. Results are written straight into your library and stay there.
Build harmonic sets that flow, find the tracks that actually mix in key, and sort your collection by tempo for the right energy at the right moment. The kind of metadata DJs pay subscriptions for. Yours, computed locally, for free.
Your Library. Offline.
No accounts. No telemetry. No cloud. Cassette reads your local files and keeps everything in a blazing-fast local database with gapless playback and seamless crossfades, every single time. Your music doesn't disappear when a subscription lapses or a server goes dark.
Accent Colors
Fourteen hand-picked accents that recolor the entire interface in an instant. Waveform, spectrum, controls, highlights, all of it. From Acid Lime to Bright Teal, the whole app shifts to match your mood the moment you pick one.
Drag the slider and watch it change.
Visualizers Coming Soon
Real-time visualizers rendered with native GPU shaders, locked to the live FFT beat detector so every pulse moves with the music. Because they run on the graphics card directly they stay buttery smooth without ever touching your playback.
Graphic Equalizer Coming Soon
A 10-band graphic EQ built directly into the player. No plugins, no external apps, no routing headaches. Boost the low end, tame a harsh high-mid, carve out the perfect listening curve for your room or your headphones.
Every adjustment is applied in real time through the same audio engine that drives playback, so what you hear is what you get. Clean, transparent, and zero latency.
9D Music Effect Coming Soon
A spatial audio engine that wraps sound around your head in 360°. Designed for headphones, it transforms any stereo track into a fully three-dimensional experience. Instruments drift left, right, behind you, above you. It doesn't feel like a filter. It feels like a different room.
One click to enable. Works on any file in your library, no special encoding or re-download required.
Headphone Profiles Coming Soon
Every pair of headphones has its own character. Some are bass-heavy, some are bright, some dip in the mids. Headphone profiles let you save a custom EQ curve per device and switch automatically when you plug in. Your Sony WH-1000XM5s sound different from your Sennheiser HD 600s, and Cassette remembers both.
Cassette ships with a curated library of professionally tuned profiles for major headphone brands including Sony, Sennheiser, Audio-Technica, and more, ready to select and use out of the box. Set it once. From then on, every device sounds exactly how you want it, not how the manufacturer decided it should.
Metadata Editing Coming Soon
Wrong artist name. Missing album. Tracks numbered out of order. It happens to every library. With Cassette's built-in metadata editor you can fix titles, artists, albums, track numbers, genres, and artwork without leaving the app. Changes are written straight to the file, permanently, no third-party tagger needed.
Edit one track or batch-edit an entire album at once. Your library, finally organized the way it should have been from the start.
Automatic Artwork Coming Soon
Missing artwork is one of the most common library headaches. Cassette scans your collection, identifies albums with no cover, and fetches high-resolution artwork automatically. No manual searching, no copy-pasting image URLs. It fills the gaps while you listen.
Everything happens locally and on demand. You review what gets applied. Your files, your artwork, your call.
YouTube Playback Coming Soon
Found a live set, a rare B-side, or a mix on YouTube? Paste the link into Cassette and it streams the audio directly. No download, no browser tab, no ads interrupting your flow. It lands in your queue like any other track, with crossfade, EQ, and the spectrum analyzer all working as normal.
Add it to a playlist. Let it crossfade into your library. Treat it exactly like a file you own, because for the duration of that session, it is.
And So Much More
Everything you've seen is only the surface. Cassette is packed with thoughtful touches and power-user tools, with more landing in every beta build.
Seamless transitions between tracks, every time.
Check mono compatibility with a single click.
Build and organise your library exactly how you like it.
Drop a folder and Cassette builds playlists from your directory structure, automatically.
Find anything in your collection instantly.
Play, pause and skip from your keyboard or headset.
Index huge libraries in seconds into a fast local database.
Show what you're listening to in your Discord status.
Pick the exact audio backend mpv uses to reach your device.
Send playback to any hardware output on your system.
From mono to 7.1, request the speaker layout you want.
Lock output to 44.1 kHz right up to 192 kHz, or auto.
Platform
● Available in Beta
Windows 10 / 11 · x64
○ Coming Soon
Apple Silicon + Intel
Cassette is invite-only right now, and spots are limited. Get on the list and we'll reach out the moment one opens up. macOS is on the way.
Request Beta Access