I am not an expert in sound staging (gotta talk to Doug about that one- in fact, I have my suspicions that your anonymous client might be Doug), but I want to make it clear that there's going to be two separate levels of discussion here: The sound staging of MP3 files at various bitrates, and the sound staging of the Empeg's output channels.

Clearly, in order to make an apples-to-apples comparison, you'll need the Empeg to be able to play raw .WAV files. Now, I'm a firm believer that high-bitrate MP3 files can sound every bit as good as the original source material, but there's some well-known technological limitations to MP3 which might affect the soundstage. Lack of ultra-high-frequency data, for example. This isn't the Empeg's fault, it's the fault of the MP3 file format.

Once you get the Empeg to play raw .WAV files, and get a situation where you can do a true comparison between another stereo and the Empeg using the same amps/speakers, there's still another thing that needs to be taken into account before you can make an apples-to-apples comparison: Equalization. All equipment, whether home-stereo or car-stereo, has a different EQ response curves even when set "flat". Car stereos especially I've noticed to be pretty bad in that they boost the highs and lows unnaturally even in "flat" mode. The Empeg's output, IMHO, is flatter at the default settings than other consumer car stereos I've heard. So you'll have to take that into account before making soundstage comparisions.

Finally, once you've solved the above problems, any direct equipment competitions should always be done double-blind to get accurate results.

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Tony Fabris