Yeah, as far as I can tell. I get the expected increased impulse ringing with the mixer SRC 96 to 44.1khz, but the ultrasonic crap from the players is reduced, and all downstream analog gear, including the headphone amp, headphones, amps, and speakers should perform better.
I subjectively notice that weird energy or distortion to the treble at 96khz with the SC Prime players or sending in 44.1khz from old players to upsample is now absent. There’s no way I’m actually hearing the players’ ultrasonic garbage itself when the mixer’s set to 96khz, but it seems to be causing signal-correlated noise in the audible bands that gives a sense of fatiguing lift even though the mixer otherwise measures clean & ruler flat.
It doesn’t 100% attenuate the noise past 25khz (it’s not a brick wall filter), and you’ll still get the rest of the SC Prime players’ sound characteristics (grimy, smeared both in frequencies & transient timing, and rolled off), and, combined with the X18xx constrained sense of dryness and not the best low-level resolution, the whole combination is certainly a bit mushy, dull, constipated, and not a crisp, taught, pristine, vibrant sound like an old Pioneer CDJ-1000 into a Tascam X-9, but on a positive note, the Prime combo set up this way is probably less fatiguing at high volumes. Granted, this combo requires higher volumes to hear fine details that other combos seem able to render better at lower volumes.
As for the A9, it seems to at least reduce some of the bloat to the lower frequencies from the earlier digital DJMs prior to the V10, even if the A9 otherwise sounds mostly like a 900NXS2. Not bad, but certainly won’t win over others who already despise the Pioneer front-end sound at high volumes. Personally, I would like the option to listen to Prime at lower volumes and hear that kind of resolution, and I think the X1700, MP2015, and DB4 with DJ software easily demonstrates such a happy medium sweet spot compared to either Pioneer DJ or new Denon DJ mixer ‘voicing’… and that in itself is notable considering those are three digital mixers that all have their own unique flavor. I think at this tier of digital sound, some amazing nuance is possible. First world problems.
If I had to choose only one of those three aforementioned (for me, near Goldilocks-sounding) digital mixers, though, it would probably be the MP2015, as it compels me to mix and focus on the DJing. Sure, all the retro-like rotary’s knobs kind of look the same, especially in the dark, but the X1700’s euphonic sound would cause me to lose myself in just listening and stop DJing, and the DB4 either causes confusion or, once you get the hang of it, is basically a giant options & effects rabbit hole that’s hard not to get lost in instead of DJing. As great as the MP2015 sounds, I never got so distracted by listening or features that I couldn’t focus on the mixing; in fact, sort of the opposite: it focuses you on it. And yet, still I’ve got the Prime mixer set up right now for the integration stuff. 
Correction: You only need 48khz to roll off the ultrasonic garbage.
they’re set to 220hz for the low shelf and 2kHz (or 2.2kHz) for the high shelf.
