DAC Measurements vs Actual Experience

If any of either if these DACs uses bit-stripping for volume control, a pre WILL make a difference for sure!

The ML390S processor e.g. uses resitor ladders in the analogue domain for volume control, and STILL, going straight (circumventing the volume control) into the ML326S pre, just sounds more 'normal' (less hyped up digital). 

Unless maybe you are considering using a top dCS type DAC straight into your amp, a good pre, and even a solid state one, will make for a more natural sound quality. 

Test it out for yourself and you'll hear.
I 'm not the only one that made that experience either.

That thread by Whitecamaros and his ongoing amp testing endeavours, came to a similar conclusion quite more recently, if you care to read through the tail end of his very long thread, - and incidentally so did John Atkinson of Stereophile some time back as well

So, listen and find out for yourself - since there is disagreement already on this issue. 
Michélle 🇿🇦 

Big difference between accurate and personal preference. The Benchmark may be a far more accurate DAC, but that does not mean for you it is the better DAC.  If you have some ability to set absolute volume though, try to listen at exactly the same volume. One thing you can be confident in, you are not doing anything wrong.

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? 

Yes perception and measurements can disagree. I'm a measurements guy and I also like accuracy, I had a Benchmark DAC3 and liked it I found it very "musical ". The only reason I sold it is I got a new integrated amp with room correction and I really couldn't tell a difference between it and the Benchmark. The PS Audio as you mentioned doesn't measure well it has more noise in a way it is more like vinyl or what a lot of audiophiles say warm, analog like, natural etc.. which isn't uncommon for poor measuring DACs. Some prefer that sound, it's more what we grew up with and associate with sounding right. I will probably get jumped on with what I say they often do, there is nothing wrong with liking what you like or preferring and following your perceptions instead of the measurements don't get hung up on how it measures. Another thing you could try is listen with your ears and not your eyes. Try to get someone to help out and listen to the DACs blind it might surprise you. 

Yes, of course, perception and measurement can, and in many situation, actually WILL,
 disagree. WHY?

In my experience it is something to take as a ’given’, something to accept - not easy actually.
Something even more hard to learn is, the level of ’SQ limitation’ of one’s front-end feeding one’s speakers - THIS includes your cable/system synergies, big time!

Something I had to learn quite recently after over 25 years of looking - in the wrong places too.

In my case, I had taken for granted that my Transparent Ultra, pre to amp, was ’beyond reproach’.
Turns out that was not quite so!

A more like accidental change, of this item (Transparent), for a Madrigal HPC XLR (25 years old!) affected my digital (and analogue) performance most profoundly!

Former harsh like digital sounds, trying to mellow down (make mor 'musical') by e.g. CDP interconnects, using another DAC, with very pricy Transparent Reference digital interconnect, and on - all was of rather marginal outcome.

The ’right’ pre to amp interconnect, all of the sudden, ’changed’ digital harshness into... previously unheard DETAIL, AIR, TONALITY, CLARITY etc.! 

So, the looking for more ’warmth’ in digital reproduction, in this case turned out to be just a band-aid for low cable/system synergy.
This is just an example for what can happen if one ’looks’ in the wrong place - based on some long held assumptions.

I hope this makes some sense, as its not a very easy thing to get accross.
Michélle 🇿🇦