This means, first, that the treble region sounds balanced. The PS1000s have a treble region that seems appropriate (measured against the sound of live music) in relation to the midrange. That’s good, though I think this is the easiest item on the treble checklist.
To have great treble, though, one also has to make headphones whose treble is balanced within the treble region. This is where most headphones fall apart, to a greater or lesser degree. They have a dip somewhere or a peak or both. It can take a while to hear this, because some driver resonances are in a very small region and thus aren’t triggered by most music (or you miss it in the mix). Well, folks, I’m here to say that the Grado PS1000s have fewer of these treble problems than the other headphones I’ve heard. On disc after disc the treble simply sounds clear, and the tonality of each instrument comes through. That is, each treble-heavy instrument sounds like itself. ‘Sounds easy, but it isn’t.
Finally, treble performance needs to be clean, with good dynamics. The PS1000s come through here as well, by offering a very low distortion treble sound. You particularly notice this via the superb instrument-to-instrument separation on offer here. Grain, hash and noise are missing, so you just hear the instruments. Micro-dynamics are well done too, with the decay of voices and instruments heard very easily.
A note of caution is in order, though. Many if not most modern D/A converters have treble problems, particularly with transients. I don’t know how suitable the PS1000s would be with the splashy treble many have become accustomed to. I don’t see why they would fare any worse that lesser headphones, but you would be advised to check this out. The converse of this is that with standard issue DACs you may not fully appreciate the treble achievement of the PS1000.
The qualities of the PS1000 treble extend into the mid-range. Instrumental separation is excellent, and instrumental tonality holds up well. One indicator of the midrange excellence of the PS1000 hits you when you notice that there is almost no discernable discontinuity between the midrange and the treble. While many headphones use a single driver and thus have no mechanical discontinuity, this doesn’t prevent them from having sonic flavors that differ across these frequency regions. Not so with the PS1000s.
When we come to macro-dynamics, though, we get to an area where the PS1000s are good but not great. On orchestral tuttis and power guitar the PS1000s never put a foot wrong, but in this conservative approach they also don’t quite capture the punch of the real thing. I did use my two favorite headphone amps with the PS1000s, and found that the all-tube Woo Audio WA22 yielded better results largely because it allowed these dynamics to breathe a bit more. With great headphones ancillary equipment will matter.
That said, I think the transition to the bass and the bass performance is the weak spot of the PS1000s, and is partly if not mostly responsible for my less than complete endorsement of their macro-dynamics. Grado has built a slightly warm bass balance into the PS1000, which is musical if not precisely accurate. Bass instruments are present and accounted for and the mix of band members sounds right. But bass transients seem a little soft, as if there is some resonance in that region or perhaps there is an upper bass dip. If you are a bass detail fanatic, these might not be your headphones.
Finally, as readers of my past reviews will know, I like to consider the overall vividness of a headphone, which is ability of the headphone to make music sound intense and realistically alive. The PS1000s are quite good in this regard, thanks to their excellent micro-dynamics and ability to render complex mixes without getting muddy or confused. They don’t have the “slam” on big material that some ‘phones do, and the transient sound is well controlled, so the sound isn’t as exciting as some competitors. Nonetheless, the transparency of the PS1000 creates a sense of realism that will get to the soul of music for many.
On Alison Krauss and Union Station’s song “Stay” [Alison Krauss & Union Station – Forget About It, Rounder], Alison’s voice, which is rather light, occasionally gets into a range where there is some slightly sibilant stridency from other headphones, but here the PS1000s sound remarkably clear and distortion free.