As noted at the outset, there is no such thing as “standard” voicing for the PRM; its sound will be whatever your personal tuning settings may dictate. Still, as a means of enabling readers to compare the PRM to other monitors that Playback has reviewed, I thought I might talk about how it sounds when the Personal Reference Tuning Box voicing control knobs are set in their baseline “50/50/50” positions.
With 50/50/50 settings, the PRM sounds very much like an Ultimate Ear In-Ear Reference Monitor (IERM) on steroids. Here’s what I mean by that remark. The PRM (with 50/50/50 settings) has voicing very similar, though not identical, to the IERM, meaning that you hear very smooth and evenly balanced frequency response—a balance where what you hear is pretty much exactly what’s on the record. I did find, though, that with the 50/50/50 settings in place the PRM’s bass output is perhaps just a smidgeon leaner than that of the IERM (this isn’t too surprising when you consider that the IERM was voiced to sound much like the in-room response of a very accurate monitoring-type loudspeaker, where a certain amount of room gain would typically add a touch of bass lift).
Two important differences stood out for me, though. First, the PRM offers a noticeable improvement in resolution—especially on very fine, low-level sonic details—vis-à-vis the IERM. Second, the PRM offers even more stouthearted and explosive dynamics than the already excellent IERM. My point, here, is that UE has managed to take what many regard as a reference quality monitor and build upon its strengths in creating the PRM. In short, the baseline performance of the PRM raises a bar that has already been set very high.
But the custom voicing aspect of the PRM takes performance to an even higher level. The Personal Reference Tuning Box is set up in such a way that you can make anything from ultra subtle adjustments that are just barely audible on up to quite sweeping changes if you so desire. The beauty of the system is that you’re completely free to dial in your ideal sound without having to worry about pleasing anyone else. This, to my way of thinking, represents the ultimate in sonic personalization.
Some Playback readers who know of blogs I’ve written about the PRM have asked if the sound of the finished monitors really does match up with the sound dialed in at the Personal Reference Tuning Station. The answer, at least in my case, is that the match between the test PRM and the final PRM seems excellent, meaning that—as near as I can tell—nothing got “lost in translation.” A UE representative told me that my personal tuning settings were fairly subtle ones, so the fact that those settings were preserved in the finished product speaks volumes for the precision and repeatability of the UE manufacturing/testing procedures.
Interestingly, I found that PRM—much like some of the great loudspeakers I’ve heard and/or reviewed over the years—tends to have a “sweet spot” in terms of playback volume level, where the monitors sound their best with a given response curve applied (I believe some curves will work better for louder averaging listening levels, while others will work better for lower levels). For this reason, I would suggest that prospective customers listen at what are, for them, typical volume levels when picking tuning settings for their personal sets of PRMs.
How do I like my PRMs? Well, they’re the most enjoyable in-ear monitors I’ve ever heard, which comes as no surprise given that they were voiced by and for me alone. The beauty of the PRM system is that it makes “ideal sound” available to any listener—offering a sound that, as UE points out, can be “as personal as your fingertips.”
I could cite example after example of the PRM’s sonic excellence in action, but let me select just a small handful to illustrate the PRM’s capabilities.
On “Freddie Freeloader” from Miles Davis’ classic Kind of Blue [Columbia], the ride cymbal that does so much to supply the song’s wonderful “late night in a club” feel sounds essentially perfect: delicate, shimmering, and clear, yet in no way overstated. Similarly, the acoustic bass has the expected “woody” tonality and exhibits a just-right touch of gravitas for a sound that is weighty, but not overpowering or boomy. But the real piece de resistance is the lovely sound of Miles’ trumpet: it is perfectly clear, has appropriate levels of detail (you can hear mouthpiece/embouchure noises and the subtlest of modulations), and shows that indescribably captivating, melancholic quality that has won the hearts and ears of jazz enthusiasts for decades. The only thing I think would compare to the PRM’s performance on this track would be a very, very expensive pair of high-end loudspeakers or perhaps an also expensive set of high-end full-size headphones (think Audeze LCD3 or Stax SR-009).