Is playback really lossless?
The FLAC preview preserves supported 16- and 24-bit sources. A 32-bit float source is converted to 24-bit for preview.
For supported 16- and 24-bit lossless sources, the FLAC preview preserves the decoded samples. A lossy source such as MP3 remains limited by its existing encoding. Selecting an optional codec preview applies another encode.
32-bit float sources are quantized to 24-bit for FLAC preview. Values above full scale can clip in this conversion. Check the preview or provide a suitable fixed-point review file when that matters.
The delivered original is not re-encoded. Each delivery file has a SHA-256 checksum that can be used to check byte-for-byte integrity after download. This is separate from the playback path.
If a project mixes sample rates, the player plays each version at its own rate when supported. If it falls back to playback at another rate, the LOSSLESS pill turns amber and reports the rate in use. Browser, operating-system and output-device settings can still affect what reaches the listener.
Fair Loudness and the client loudness preview reduce playback gain without changing the stored file. Turn them off, and select Lossless rather than a codec preview, to review without those playback adjustments.
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