I've been listening to the PK2's with a Go-Vibe V5 (the recently released one with AD8397/AD825 opamps, regular gain). Here's what I hear: these $69 buds give me most of what I love the most from my Grado SR225, PLUS most of what I love the most from my Ety ER4S, all in one package - I'm slack-jawed amazed!!! Here WAS my dilemma (before the PK2's): I'd be at work listening to the Ety ER4S on the above-mentioned Go-Vibe V5, and I'd REALLY enjoy the high end loveliness and gorgeous detail of my favorite music (but I'd miss the crunch/chunk, larger soundstage and low end extension and impact of my SR225). Then I'd go home and listen through my SR225 - and revel in their clarity, transparency, crunch/chunk and low end fullness (but miss the high end gorgeousness I was hearing at work). Why can't I glue what my ear loves about these two phones together?
Enter the PK2's. The lows: they don't have as much low end as the SR225, but enough that I don't miss it. For example, on the CD "LushLife" by Bowery Electric, on the track "Psalms of Survival", nineteen seconds in, a low bass wave hits which, on my SR225, I feel it deeply down to the bottoms of my feet. I really miss it with the Ety ER4S, because I feel it less deeply and down to my chest. On the PK2's, I feel it deeply down to my knees. Enough that I DON'T sigh with a little frustration, wishing I were listening to that on the SR225. The mids: beautifully full, lush and lifelike. Human voice sounds full-size (neither like a miniature in the head, nor like an overblown close-up magnification). The highs: when the highs come from high soprano voice or an upper register instrument, they are natural and lifelike; when the highs come from electronic instruments and the production is full of the beams-of-light-visible-through-fog-or-smoke effect, the highs can be as ethereal, diaphanous and otherwordly sounding as the producer intended (such as the "Ardor" CD of Love Spirals Downwards). One of my favorite albums (for years now) is "Wrecking Ball", by Emmylou Harris (produced by Daniel Lanois). It takes the ER4S to hear the subtly beautiful features of Emmylou's vocal delivery on the intensely intimate track "Goodbye". Well, the PK2 delivers that subtle detail with sufficient beauty that I don't miss the ER4S when I listen to this favorite at home.
Having made all of these sonic dissection types of observations, let me pull it all back together into the living experience of music and say that the PK2 delivers the full range of the dionysian (visceral, body-moving, ear-tickling) fun-with-abandonment as well as the appolonian (internal/soulish, intimate, subtle, visionary) transporting adventures on which our music can take us - all in one phone.
So, here is a $69 pair of earbuds delivering enough of two $200 earphones, one full-size, one IEM that I can listen to music without sighing about wishing I were listening to some feature of it on my OTHER set of phones. There is much value in having this range of sonic capability/versatility in one set of phones. Just so that there is no misunderstanding, all of these observations were made listening to the PK2 on my work and main home rigs using the Go-Vibe V5, with AD8397/AD825. With this well-suited amplification, the results, to me, are simply stunning.
With this degree of satisfaction from the PK2, at this point, I'm not in the least even curious about how the PK1 sounds (with apologies to jdimitri, who is doing his best to stir up interest in the more expensive (and I'm sure worth every penny) PK1).
