Vox Machina

A purpose-built USB audio engine for listeners with serious local libraries. The Engine delivers bit-accurate playback to UAC1 and UAC2 DACs, with a transport path built for fidelity and a library system for listeners whose libraries exceed Android's reach. USB DAC required.

ENGINE
Three fidelity doctrines govern the Engine:

Wide — the Engine selects the best available format. All tracks adapt to fit.

Source Matching — native sample rates are preferred above all else. The Engine seeks fidelity before convenience.

Bit Perfect — integer PCM delivered to the wire without float conversion, without DSP, without headroom adjustment. Native DSD up to DSD2048 via dedicated transport, if your DAC and device are sufficiently sanctified. Mono and stereo sources only. Nothing is added. Nothing is taken.

Four pipeline domains carry the signal: Float32 for processed audio, Integer Passthrough for bit-perfect PCM, DoP for DSD over PCM framing, and DSD Native for raw 1-bit delivery. The domain is chosen by doctrine, not by guess.

Three fidelity tiers declare what the engine does to your signal — BIT PERFECT, LOSSLESS PROCESSING, DSP ACTIVE — with honest ATT suffixes when digital volume is engaged. The Engine does not lie.

SEALED WITNESS
Bit-perfect is not merely declared; it is proven. The Sealed Witness computes CRC32 integrity checksums at two points in the pipeline — the decoder's output and the moment of USB submission — and compares them in real time. If they match, the signal has crossed the Engine untouched. If they diverge, the Engine states the cause. No other mobile player verifies its own integrity chain at the wire.

DSP
31-band parametric and graphic equalizer with per-band bypass, logarithmic Q, direct gain entry, and automatic headroom attenuation to prevent clipping from EQ boost.

Partitioned overlap-save convolver for headphone impulse response correction. Load an AutoEQ profile from an integrated library of thousands. Crossfeed for speaker-like stereo imaging on headphones. Channel balance with per-channel precision.

Under Bit Perfect, all DSP is absent. The processors are not instantiated. The float domain is never entered.

RESAMPLER
8192-tap polyphase windowed-sinc resampler. 128 taps per phase, 64 phases. Blackman-Harris window with 95% passband preservation. Four selectable filter modes — mathematical, minimum phase, apodizing, and brickwall. The resampler engages only when the source sample rate does not match the connected DAC. When it does match, the resampler does not exist in the chain.

DSD
Native DSD for DACs that bear the mark — DSD64 through DSD2048. DoP framing for broad compatibility. DSD-in-WavPack and DST-compressed DSDIFF are decoded natively and routed through the same pipeline without decimation. When EQ or digital volume is required, DSD is decimated to PCM. The Engine confesses the cost; it never degrades silently.

DECODING
Native FLAC via dedicated C bridge. DSF and DFF containers parsed by dedicated forges, including DST-compressed streams. FFmpeg for everything else — MP3, AAC, OGG, WAV, AIFF, ALAC, WavPack, APE, Opus.

LIBRARY
A music-collection manager for the audiophile. Grant the Engine access to your music folders and its custom-forged scanner surfaces complete collections where stock MediaStore indexers fall silent or return them only in part: DSD, WavPack, APE, AIFF, FLAC, WAV, Opus, and more — alongside the companion files that make a true library whole: CUE, M3U, and folder-level album artwork. No format left behind. No folder unreached. No companion lost.

PLAYBACK
Gapless playback via a proprietary mechanism — same-format transitions are zero-gap via a reservoir that decouples decode timing from USB delivery. Bit-Perfect Playlist probes your library against the connected DAC and admits only what reaches the wire unprocessed.

DIAGNOSTICS
Real-time telemetry with one-tap export. Every parameter declared and auditable.

Android 10+. arm64. USB DAC required.