Roger,

You're confusing data compression with dynamic range compression. "Sound Check" will normalize your data on playback and normalization will apply dynamic "compression" or expansion to normalize the volume (i.e. it will muck with the data stream, which for some of us is a no-no). Adjusting the Volume on the Mac or any computer that is feeding your system digitally is generally considered a bad thing (to some of us). The convenience (of normalization) may out weigh any loss in quality for some people. But I would never do it.

Now if you`re hooked up with analog outputs (on the computer) it may adjust the Analog Gain (I doubt they would bother to be that careful). But the analog outputs of any computer I know of is not that great (not to mention the added D to A and A to D for most of us DIgital Preamp folks) and the whole point of discussing quality is moot.

"Sound Check" does work like Replay Gain. But both would suffer as discussed above if you adjust volume in the digital domain. The only way to do it right would be how I suggesed above using the RS-232 interface which I might take on has a hobby project one of these days.

- Fiddler (IMHO)

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