No, you can use any native format that supports 24 bit, FLAC isn't the only one. WAV doesn't support greater than 16bit but the other formats do that are still native. You can trick it but using a different native format with different rules applied. If you don't hear a differnce worth while on HDCD processing but do on WAV vs FLAC I don't know what to say.

- Fiddler (IMHO)

If you think listening to music is fun, try learning an instrument.
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