One particular way in which the PS Audio DAC purportedly falls down is the level of noise, possibly due in some way to the use of a transistor output. I confess that I'm not well versed in circuit topology and the idiosyncrasies of certain configurations, but the reviewer from Audio Science Review speculated that that could be the cause.
Another shortcoming is the somewhat limited dynamic range as compared to the Benchmark. I was especially concerned about this given that I have inefficient (86dB/watt/m) speakers. If my logic is correct, a diminished dynamic range with those speakers might make it more difficult to distinguish transients and also some of the more subtle inflections in music. So far, this hasn't borne itself out in my real-world tests. But that's one way in which I'm doubting my own hearing. *Should* I be able to tell a difference here between DACs?
The level of detail that each DAC is able to extract from the program material, at least as far as I can discern, is virtually identical. The female vocals in the final 2 minutes of Roger Waters' "Amused to Death" has been my go-to challenge for a component's ability to convey delicate nuance. Neither DAC has demonstrated any apparent advantage.
As far as stepped volume control goes, the DirectStream touts a "bit perfect" digital method. I'll take their word for it. I'm not sure what the Benchmark's configuration is, but I cannot detect any deterioration of performance at any of the levels I've tried (all further clockwise than the 12 o'clock position). I'm evaluating each at the same volume, or as close to the same volume as possible, such that I cannot tell the difference. I'm sitting in a quasi-near-field position relative to the speakers (~6 feet away), mostly using a volume where the system is conveying energy convincingly, but falls well short of concert-level volume. Evaluations have also been made at more "whisper" levels with volume control being done using my streaming device.
The differences that I'm honing in on have more to do with grain, soundstage and the admittedly vague descriptor of "musicality" than anything else. But I have this nagging feeling that I need to be listening for something more; something that enables me to look at my experience critically compared to the measurements and say, "Ah, yes. There's where my perception is supported by the data." And yet, that's not happening.
These two units each bring a very strong game. I would probably be quite happy with either of them. And yet, I don't want to get this decision wrong. Maybe what I'm asking for here is a "listening lesson" from experienced audiophiles. But to the larger issue, do perceptions and measurements often disagree?
