A native Android hi-fi music player with TIDAL and Qobuz streaming, local-library playback, encrypted collections, a 32-processor DSP mixing console, a 10-band AutoEQ driven by 4,000+ headphone measurements (squig.link + AutoEq), a libusb USB Audio Class bit-perfect bypass for external DACs, and a real-time ProjectM visualizer.
Formerly MonoTrypT. The launcher icon and About screen now read "Tryptify"; package id, storage paths, and existing installs are unchanged.
Download the latest APK
— Android 8.0+ (API 26), sideload or adb install.
- Rebrand to Tryptify. Launcher name, About tab, and version footer updated; package, app id, and existing user data are untouched.
- Qobuz catalog source. Pickable source mode in Settings — TIDAL only,
Qobuz only, or both fanned out in parallel at search time. Album / artist /
track detail screens,
QobuzCachedstream resolution via the configured trypt-hifi instance, and per-track QobuzIdRegistry routing so a Qobuz id never accidentally falls through to TIDAL. - Bit-perfect USB DAC bypass. UAPP-style libusb-backed UAC1 and UAC2 driver, end-to-end iso pump, sample-accurate feedback-EP pacing, software volume + hardware-key control, exclusive-mode interface claim. EQ, AutoEQ, and the mixer DSP keep working on the bypass path.
- Rig-aware AutoEQ. 12 squig.link sources merged with the existing AutoEq GitHub catalog, rig taxonomy (B&K 5128, GRAS 43AG-7 / 43AC-10 / 45CA-10, IEC 711 clone, MiniDSP EARS, Uploaded), pinned-left "Uploaded" section, instant chip feedback, long-press delete on user uploads, FR measurement cached across sessions.
- Synced karaoke lyrics with a blurred-album-art backdrop, plus an LRCLib fallback when TIDAL has no lyrics for a track.
- Per-track Share sends the FLAC directly (downloading on demand if it isn't already local).
- Polish: infinite-scroll unified search, downloaded-album art in the
catalog, Ko-fi link in a new About tab, NDK bumped to
29.0.14206865with explicitlibc++_shared, vsync toggle for the ProjectM surface, and a pile of audio-safety / lint / volume-state fixes.
A full per-commit list lives in the 1.5.0 release notes.
Catalog & playback
- Two streaming sources — TIDAL HiFi (lossless FLAC, 24-bit hi-res) and a user-configurable Qobuz instance (trypt-hifi compatible). Source mode is user-selectable; both run in parallel on search by default with Qobuz failures isolated so they can never block the TIDAL path.
- Local library via MediaStore with embedded-tag reader, incremental sync, and filesystem watcher.
- AES-256-GCM encrypted collections with transparent decryption at playback time.
- ReplayGain (track / album with preamp + peak protection), gapless playback, queue with drag-to-reorder + shuffle + 3-mode repeat, variable speed.
- Offline FLAC downloads via WorkManager, with optional LRC export and on-demand share-to-FLAC.
- Chromecast through Media3 Cast, Glance home-screen widget, Android Auto media browser.
- Last.fm and ListenBrainz scrobbling, Supabase-backed cloud sync of favorites / history / playlists.
- Synced karaoke lyrics (TIDAL + LRCLib fallback) with blurred-art backdrop.
Audio processing
- DSP Mixer — 4 buses + master, up to 16 plugin slots each, 32 native processors. User-selectable block size (4096 / 8K / 16K). True bypass when the mixer is off.
- AutoEQ — 10-band parametric generator, 10 target curves, 4,000+ measurements from squig.link + AutoEq, rig-aware filtering, custom measurement upload.
- Parametric EQ — ±24 dB per band with bundled and user presets.
- Oxford / Seap effects — separate Inflator and Compressor screens for the dedicated processors (outside the bus plugin chain).
- ProjectM visualizer — OpenGL renderer with album-art color tinting, optional vsync disable.
USB DAC bit-perfect bypass
- libusb-backed UAC1 and UAC2 driver — claims the streaming interface from the kernel, sets the alt setting, negotiates the sample rate via the clock entity, and drives the iso endpoint directly with a preallocated transfer pool and a single-producer / single-consumer ring buffer.
- Sample-accurate UAC2 pacing using the asynchronous feedback endpoint; graceful UAC1 fallback for devices like the Focal Bathys that don't speak UAC2.
- Software-volume control on the bypass path with hardware-key handling, pause-silences-DAC, and a watchdog that falls back to the delegate sink if the iso pump wedges.
- DSP / EQ / spectrum / ProjectM tap all keep working when bypass is on — the mixer chain runs inline, then the post-DSP PCM goes to libusb instead of the Android audio HAL.
- Categorized error reporting (no-device, no matching alt, claim failed, set-alt failed, sample-rate failed, iso pump alloc / submit failed) surfaced to Settings instead of the old "kernel still owns it" boilerplate that was wrong half the time.
Interface
- 16 built-in palettes plus a true light "White" scheme.
- "System" theme follows the OS dark-mode toggle live; system bar icons adapt to the resolved background.
- Dynamic colors — Material You-style palette extracted from the current track's album art.
- Custom font loading, configurable text scale.
- Compose + Material 3 throughout, with a floating curved player UI designed against modern Android device screen radii.
┌─ TIDAL HiFi API client ──────┐
SearchViewModel ──┤ ├─→ unified results
├─ HiFiApiClient (Qobuz) │
└─ Local + Collections ┘
│
▼
PlaybackSource
├─ TidalStream
├─ QobuzCached ← /api/download-music + LRU file cache
├─ LocalFile
└─ EncryptedCollection
│
▼
StreamResolver → Media3 ExoPlayer
SourceMode (BOTH / TIDAL_ONLY / QOBUZ_ONLY) gates which catalogs feed
search and discovery; per-track playback always follows the originating
PlaybackSource. Qobuz failures (instance unset, network error, schema
mismatch) are logged and dropped — the TIDAL path is never blocked behind
a slow or hung Qobuz instance.
QobuzIdRegistry records (numeric qobuz_id → alphanumeric slug) at search
time so the album-detail endpoint, which wants the slug, can be hit from a
navigation route keyed by Long. Track ids are also stamped so the player
routes Qobuz-album tracks through QobuzCached instead of falling through
to TIDAL with an id TIDAL doesn't recognize.
A C++17 native library (monochrome_dsp) sitting inside the ExoPlayer audio
pipeline. ARM NEON SIMD, denormal flush-to-zero, lock-free atomic updates
between the UI and audio threads.
ExoPlayer → ReplayGain → AutoEQ / ParamEQ → MixBusProcessor (JNI) → ProjectM tap → AudioSink
│ │
Native DspEngine ┌─────────────┴─────────────┐
├─ Bus 1 [up to 16 plugins] │ default → DefaultAudioSink
├─ Bus 2 [up to 16 plugins] │ bypass → LibusbAudioSink
├─ Bus 3 [up to 16 plugins] │ (libusb UAC)
├─ Bus 4 [up to 16 plugins] └───────────────────────────┘
├─ Sum ──────────────────────┐
└─ Master [up to 16 plugins] ┘
Per-bus gain (dB), pan, mute, solo, and input-enable. Master sums active buses, runs its own plugin chain, and meters the output with peak + hold ballistics (1.5 s decay). Engine state serializes to JSON and persists in Room.
| Category | Processors |
|---|---|
| Utility | Gain · Stereo (M/S + equal-power pan) · Channel Mixer (2×2 routing) · Haas |
| EQ & Filter | Filter (RBJ biquad, LP/BP/HP/Notch/Shelf/Peak, 1×–4× slope) · Comb Filter · Formant Filter · Ladder Filter (Moog/diode, 2× OS) · Nonlinear Filter (SVF + 5 shapers) · Resonator |
| Dynamics | Compressor · Limiter (5 ms lookahead, true peak) · Gate · Dynamics (dual-threshold up/down) · Compactor (lookahead limiter / ducker) · Transient Shaper · Trance Gate (8-step, ADSR) |
| Distortion | Distortion (6 modes) · Shaper (256-pt transfer LUT) · Bitcrush (SR + bit-depth, TPDF dither) · Phase Distortion (Hilbert self-PM) |
| Modulation | Chorus · Ensemble · Flanger (barberpole) · Phaser (2–12 stage) · Ring Mod · Tape Stop · Frequency Shifter (SSB via Hilbert pair) · Pitch Shifter (granular OLA) |
| Space | Delay (up to 2 s, ping-pong, ducking) · Reverb (8-line FDN + 4 allpass diffusers) · Reverser |
Every plugin has bypass, dry / wet, and 5 ms parameter smoothing. All setters clamp inputs and reject non-finite values before reaching the real-time thread; biquads fall back to passthrough on pathological f / Q combinations.
The Oxford / Seap Inflator and Compressor are dedicated effects exposed on their own screens, separate from the bus plugin chain.
Biquads (RBJ cookbook), cubic-interpolated delay lines, peak / RMS envelope followers, LFOs, allpass chains, DC blocker, Hilbert transform, 2× half-band oversampler, lookahead buffers, Hann overlap-add crossfade, 256-point transfer-curve LUT, exponential parameter smoothers.
10-band parametric EQ that generates headphone-correction filters from frequency-response measurements.
Algorithm — greedy iterative peak-finding:
- Normalize measurement against target over the 250–2500 Hz midrange window.
- Scan 20 Hz–16 kHz for the worst deviation (sub-50 Hz weighted 1.2×).
- Invert the deviation as gain (clamped ±12 dB, ±8 dB above 8 kHz), estimate Q from the bandwidth.
- Subtract the new filter's biquad response from the remaining error.
- Repeat up to 10 bands, or stop early if max error < 0.05 dB.
Target curves: Harman Over-Ear 2018 · Harman In-Ear 2019 · Diffuse Field · Knowles · Moondrop VDSF · Hi-Fi Endgame 2026 · PEQdB Ultra · SEAP · SEAP Bass · Flat.
Twelve squig.link instances are queried in parallel on first fetch; the
existing AutoEq GitHub catalog is also bundled. Per-source failures are
silent so one dead host doesn't poison the list. Cache TTL is 24 h, matching
the AutoEq path. Sources currently include Super* Review, Precogvision,
DHRME, Aftersound, Elise Audio, Jaytiss, CSI-Zone, Acho Reviews, kr0mka, and
others; the full list lives in SquiglinkApi.kt.
Each measurement is tagged with the rig it was captured on:
Uploaded (the user's own files, pinned leftmost) · B&K 5128 ·
GRAS 43AG-7 · GRAS 43AC-10 · GRAS 45CA-10 · IEC 711 clone ·
MiniDSP EARS · Unknown.
The HeadphoneSelectScreen shows a chip row of rigs across the top with per-source rows below; switching rig instantly re-filters without a network round-trip. User uploads support long-press delete and have the headphone name auto-filled from the picked filename so saved profiles keep their identity.
CSV / TXT with auto-detected delimiter (comma, semicolon, tab, whitespace), header row detection, and European decimal format conversion. The picked file's frequency response is cached so the curve survives across sessions without re-import.
The EQ processor wraps Android's system Equalizer AudioEffect, bound to
the ExoPlayer audio session id. Parametric bands are mapped to the device's
fixed system bands using a Gaussian gain estimation model — for each system
band frequency, the contribution of every parametric band is summed based
on its distance in octaves from the band centre, shaped by Q. Gains clamp
to the device's hardware limits (in millibels). Preamp clamps against peak
band gain so the cascade can't exceed safe headroom. EQ updates in real
time via an atomic snapshot read on each audio block — no clicks during
live tweaking.
A libusb-backed Audio Class driver that takes the streaming interface from the kernel and writes PCM directly to the DAC's isochronous endpoint, bypassing the Android audio HAL.
Owns:
- One process-wide libusb context, lazily created.
- Device handle wrapping a Java-supplied
UsbDeviceConnectionfd. - Streaming-interface alt-setting selection + claim, with an
AudioControl-interface claim so
SET_CURrequests can reach the device. - A fixed pool of preallocated isochronous transfers.
- An SPSC ring buffer the audio thread writes into and the iso completion callback drains from.
- An event-handling thread driving
libusb_handle_events.
Negotiates:
- UAC1 and UAC2 — auto-detected from the descriptors. UAC1 path supports devices like the Focal Bathys that don't speak UAC2.
- Sample rate via UAC2 clock entity +
GET_RANGE, walking Selector → Source units when needed; UAC1 has its ownSET_CURhandling. Brute-forces every clock candidate before failing. - Iso
bIntervalis honoured; alts whose maxPacketSize can't fit the configured rate are rejected up-front.
Pacing: UAC2 asynchronous feedback endpoint reader for sample-accurate iso scheduling. UAC1 falls back to fixed-rate iso pacing.
Sink integration: LibusbAudioSink is a Media3 ForwardingAudioSink
wrapping a DefaultAudioSink. When bypass is hot, it runs the same
AudioProcessor chain DefaultAudioSink would (mixer DSP, AutoEQ,
parametric EQ, FFT spectrum, ProjectM tap), then writes the post-DSP PCM
to libusb. Software volume is applied on the bypass path and follows the
hardware volume keys; pause silences the DAC instantly. A watchdog with a
brief grace window falls back to the delegate sink if the iso pump wedges.
Failure surfacing: start failures are categorised (no-device, no matching alt, claim failed, set-alt failed, sample-rate failed, iso pump alloc / submit failed) and surfaced to Settings as actionable text instead of one boilerplate error string.
Sixteen built-in palettes (Monochrome, Ocean, Midnight, Crimson, Forest, Sunset, Cyberpunk, Nord, Gruvbox, Dracula, Solarized, Lavender, Gold, Rosewater, Mint, White, Clear), plus:
- System — follows the OS dark-mode setting live.
- Dynamic colors — primary / secondary slots extracted from the current track's album art via AndroidX Palette and cached in memory.
- Material You hook — SDK-gated helper ready for a future Android 12+ wallpaper-based scheme.
Status- and navigation-bar styles are bound to the resolved theme background, so icons stay legible when switching palettes or track art.
Single-module app, package tf.monochrome.android, application id
tf.monotrypt.android (kept stable through the Tryptify rebrand so existing
installs upgrade in place).
tf.monochrome.android/
├── audio/
│ ├── dsp/ # MixBusProcessor (JNI), DspEngineManager, SnapinType
│ │ └── oxford/ # Oxford / Seap Inflator + Compressor
│ ├── eq/ # AutoEqEngine, EqProcessor, FrequencyTargets
│ └── usb/ # LibusbUacDriver, LibusbAudioSink, exclusive controller
├── auto/ # Android Auto media browser service
├── data/
│ ├── api/ # TIDAL HiFi client, Qobuz (HiFiApiClient), squig.link, instance failover
│ ├── auth/ # Google Sign-In + Appwrite OAuth
│ ├── cache/ # QobuzStreamCacheManager
│ ├── collections/ # Encrypted collection manifests (AES-256-GCM)
│ ├── db/ # Room v8, 11 tables
│ ├── downloads/ # WorkManager offline downloader
│ ├── local/ # MediaStore scanner + tag reader + fs watcher
│ ├── preferences/ # DataStore settings (incl. SourceMode, Qobuz endpoint)
│ ├── scrobbling/ # Last.fm + ListenBrainz
│ └── sync/ # Supabase cloud sync
├── di/ # Hilt modules
├── domain/ # Models + use cases (incl. MeasurementRig)
├── player/ # Media3 PlaybackService, QueueManager, StreamResolver, ReplayGain
├── share/ # TrackShareHelper (download-on-demand share-to-FLAC)
├── ui/
│ ├── mixer/ # BusStrip, PluginSlot, PluginPicker, PluginEditor, DspCanvas
│ ├── eq/ # Parametric + AutoEQ screens, FrequencyResponseGraph, rig chips
│ ├── oxford/ # Inflator + Compressor screens
│ ├── theme/ # Color schemes, Dimens, DynamicColorExtractor
│ └── ... # Remaining screens (Compose + Material 3)
├── visualizer/ # ProjectM OpenGL renderer + JNI audio tap
└── widget/ # Glance Now Playing widget
app/src/main/cpp/
├── dsp/
│ ├── dsp_engine.{h,cpp} # Bus / plugin routing, metering, state serialization
│ ├── dsp_jni.cpp # Kotlin ↔ C++ bridge
│ ├── snapins/ # 32 plugin implementations + the AutoEq biquad chains
│ └── util/ # Shared DSP primitives
├── usb/
│ ├── libusb_uac_driver.{h,cpp} # UAC1 + UAC2 streaming driver
│ └── usb_jni.cpp # Kotlin ↔ libusb bridge
├── projectm_bridge.{h,cpp} # ProjectM visualizer wrapper
├── projectm_jni.cpp
└── audio_ring_buffer.{h,cpp}
Built with -O3 -ffast-math, ARM NEON SIMD, denormal flush-to-zero. ABIs:
arm64-v8a, armeabi-v7a, x86_64. Explicit libc++_shared runtime.
Room v8, 11 tables:
favorite_tracks · favorite_albums · favorite_artists · history_tracks
· play_events · user_playlists · playlist_tracks · downloaded_tracks
· cached_lyrics · eq_presets · mix_presets.
All DAOs expose Flow<T> for reactive UI.
Ktor with the OkHttp engine. 200-entry LRU cache, 30-minute TTL. Instance failover pulls live API endpoints from uptime workers, falls back to a hardcoded pool, shuffles per request; 429 responses rotate to the next instance. Qobuz fan-out has a hard 6 s per-request ceiling so a slow Qobuz instance can't block the TIDAL flow.
| Component | Version |
|---|---|
| Language | Kotlin 2.1.0 |
| DSP engine | C++17 via JNI (monochrome_dsp) |
| USB driver | libusb 1.0 (UAC1 + UAC2) |
| UI | Jetpack Compose, Material 3 (BOM 2024.12.01) |
| Audio | Media3 / ExoPlayer 1.5.1 |
| Casting | Media3 Cast, Google Cast Framework 22.0.0 |
| Visualizer | ProjectM 4.1.6 (C++17 via JNI) |
| Images | Coil 3.0.4 |