[bigiain]

> Small differences in gain are ABX able much more readily than differences in noise at the 16 vs 24 bit level.

This was common knowledge at least as far back as the mid 80s, when every hifi shop and salesguy knew to ensure the bit of gear with the highest profit margin got played an almost imperceptible bit louder than the gear the customer came in to buy during back to back testing.

[nullc]

It's also a reason why double-blind testing is important. If someone doing the setup is expecting one piece of kit to sound better, if it doesn't they'll check the configuration more, and difference in gain can come from many sources. So errors that result in higher gain in favor of the "better" candidate go uncorrected, while ones that favor the worse tends to be fixed.

Point being: it doesn't even require an unscrupulous sales person to get similar results to an unscrupulous sales person! :P