What is the path from .aiff to (assuming) pcm at the optical/usb/firewire output?

[Mr.C]

In all this discussion about Amarra, one thing has become clear: I don't know what happens to a file from point A to point B. The "bit perfect is bit perfect" line claims that there is some sort of direct conversion that cannot be messed up by software, while the "we charge for good software" people claim that there are multiple conversions that require smart software to minimize the effects of these conversions. So let's get it on the table: what is the path and what are the possible effects of software?

 

[The Computer Audiophile]

Hi Mr.C - You've asked the million dollar questions that don't have a specific answer. It's almost like asking how does one get from New York to Los Angeles? There are several routes all of which lead to the final destination.

 

That's my take on it anyway. I'm with you 100% about getting it all out on the table. I'd love it to be laid out for all to view and examine.

 

[I. G.]

Well, in the case of Apple systems iTunes (which uses the QuickTime audio engine) probably decodes the given audio file (mp3, aac, alac, aiff, wav) to 32 bit floating point PCM I guess, does the modifications (volume, equalizer, sound "enhancer" etc.) if necessary, then sends it out converting it to the output format (16/24 bit integer PCM). Sample rate is up/downsampled if necessary. If the sample rate and bit rate don't change compared to the original file and volume is on 100% and everything else is off it's going to be bit perfect for lossless formats.