Very interesting discussion here - I am a software engineer and want to clear up some points re: computing.
Let's state some facts about ALAC vs other formats:
- Lossless is lossless. The input data is the same.
- Computers are fast enough that the CPU power required to decompress lossless audio on the fly is not an issue. Any computer is 10 or even 50 times more powerful than what's needed for that.
- People hear differences
In my opinion, this means there is a bug in the decoding software. The nature of this bug is unknown but we can assume it's not delivering the right tones at the right times. Theoretically, buffering and CPU horsepower would make an ALAC stream the exact same thing as a WAV stream - but theory is not practice, and bugs do happen.
It could be a bug in the open source ALAC library (what VLC is using) or in Apple's own (iTunes) or both. It could even be a bug in some other system component that affects this and that's somehow bypassed by WAV/AIFF.
I imagine one could test this by ripping the audio stream from the sound card and comparing the WAV audio stream to the ALAC audio stream. Do this on a high end system so the ripper software doesn't introduce variations, and create averages of 10 rips with the ripper for each case.
