All of this doesn’t matter much if the sound isn’t accurate; so let’s get down to the sonic character on offer here. I tested the PS 20s using an iPhone 4 loaded with tracks ripped from CD in Apple Lossless format, the Moon Audio Silver Dragon LOD (Line Out Dock) cable and a NuForce Icon Mobile amplifier. I tested them in flight on an American Airlines flight, as well as in an office setting.
The sound of the PS 20s could give the makers of high-end earphones fits, because the PS 20s sound impressively good, especially in light of their price. Spend extra money and you can get some small improvements (small at least in the way most people think about it). For example, if you gave the PS 20s and a pair of $500 earphones to a friend, I can imagine two reactions. First, they might say the two earphones basically sound the same. They might also say they’d like a more “exciting” sound, meaning they’d like some particular frequency band to be more emphasized.
If musical accuracy is what you’re after, though, the PS 20s will do quite nicely. From about 300 Hz to 8kHz they sound pretty flat, which is a much greater achievement than might at first appear to be the case. For reasons we’ve covered elsewhere, the upper part of this range is a series of compromises that even the best headphones struggle to master. So, I was impressed with the PS 20. Female vocals, a particular challenge for headphones of all stripes, are presented by the PS 20s with an open but not shrill sound. Above and below this band the Phiatons seem to roll off slowly, but in a smooth way and with low apparent distortion. Above the mid-bass region, there is enough energy that the PS 20s don’t sound too thin, though in absolute terms I’d like to have a bit more lower mid range and more midbass.
Cymbals and other high frequency instruments are presented with admirable detail, though I think you would sense that mid and upper treble could have a touch more energy and refinement. Overall this is what I’ve referred to in the past as an “n” shaped frequency response curve and it is desirable for those who find themselves wanting clarity and smoothness in equal doses. It also works for those who object to boom and sizzle.
Because of the noise reduction circuitry, the PS 20s are also rather good at resolving low-level detail. This is important for a sense of a real acoustic environment as well as for articulating the particular beauty of certain instruments. I wouldn’t say the PS 20s are state-of-the-art here, but in practical terms they do quite well. This strength is complimented by what sound like low-distortion drivers that don’t muddy the sound, yielding good separation between instrumental lines. The net result of all this is that the PS 20s give you a very good ability to really hear “into” the music.
So, with all this goodness spilling over, what’s the catch? Well, musically there really isn’t one. But in strict terms two limitations stand out. First, as I mentioned above, the mid and low bass energy is rolled off. On my standard Jack Johnson electric bass test series (tracks 7-9 from On and On), the weight and air are notably diminished from the sound of a live mix. I’m pretty sure some people will find the balance at least a little light. On music that really depends on bass power, the Phiatons don’t sound bad, but you wouldn’t use adjectives like ‘punchy’ or ‘solid’ to describe them. Note that lots of headphones don’t do low bass very well, so I’m simply saying that the PS 20 follows that common path.
The second imperfection is an occasional sense of edge or distortion on high level transients when the ‘phones are being pushed to rather high levels. These two items—reduced midbass and some dynamic edge—mean the PS 20s might not be ideal for power music and the like. Finally, of course, there are areas that I’ve characterized as strengths in the PS 20 but where the PS 20 is not the best available headphone if you have an unlimited budget. These remarks have to be taken in the context of the intended market.
Which brings us to the question of value, which, like judgments about beauty, is ultimately up to you. But consider the facts: The PS 20s cost $149; they sound very good, particularly if musical accuracy in the critical midrange is the goal; they’re comfortable; they work better than many standard earphones on airplanes; and they can be driven by an iPod sans amplifier. That seems like the basic recipe for high value to me.
• Consider this product if: Mid-range and treble clarity and smoothness are critical to you