So far, then, the Grado PS500 haven't exactly excelled, though it's worth noting that few of our complaints are truly problematic for using these headphones in a dedicated home listening situation. Nevertheless, the they do rely almost completely on their sound quality to win hearts and thankfully it's here that they deliver.
The most immediate impression is how even they sound. There's no forced bass, no shrillness to treble and no over-egged mid-range warmth. These phones just deliver precisely what's presented to them. We were cautioned by Grado's PR that we may be unimpressed at this very fact, as there's no 'wow' factor from a fat bottom end or forced mid-range, but he couldn't have been more wrong.
From Chopin to Children of Bodom, La Roux to Led Zeppelin, Pink Floyd to Prong, all are delivered with the requisite detail, warmth and clout that the tracks demand. Perhaps real bassheads will miss the constant pummeling that some sets give but where required these headphones still extended incredibly far and deliver with surprising gusto – you're often caught out when a bassy track or the rumble of an explosion in a movie kicks in. Indeed this is precisely what makes them great for mastering, and is why these are from the 'professional' series.
Perhaps the biggest benefit of this flat sound is that the top-end doesn't feel forced, and thus doesn't become fatiguing. It's surprisingly just how many supposedly high-end ear and headphones actually become tiring after just an hour or so's listening. With these you can listen for hours… well, if the overall fit is to your liking.
Openness is also a key characteristic. That open-back design gives a sense that the sound is filling out the room around you so you can pick out instruments as though you were there. Being headphones rather than surround sound speakers you don't get quite the sense of front to back depth but we've heard few headphones that do better. One exception is these 'phones bigger brother, the PS1000. Their over-ear design allows the earpieces to be held just that bit further away from the ear, opening up the soundscape even further, in all directions. The downside of the PS500's open back design is you really need to be in a quiet environment to get the most from these headphones.
It's almost difficult to know where to begin when it comes to talking about the detail these headphones can reveal. The old clichés of being able to hear the scrape of the pick on a guitar string, the creak of the sustain pedal on a piano or the subtleties of a singer taking in a breath are far surpassed by what's on offer here. Listen carefully and you'll pick out different guitar layers, the squeak of a drummer's stool, or the shift in timbre as a french horn player cycles their circular breathing. It's mesmerising stuff.
You may at this point be wondering just what's missing compared to the likes of the three times more expensive PS1000. Well, the frequency range of the two sets tells something of the story. The PS1000 go from 5-50,000Hz while the PS500 run from 14-29,000Hz. Clearly a large chunk of the PS1000 range is actually inaudible but by extending so far they somehow manage to add extra space to your listening, moving you one step closer to feeling like you're truly there rather than just listening to a truly great recording. Crucially, like the PS1000, the PS500 drivers are matched to within 0.05db of each other, which goes a long way to building the truly astonishing soundscape.
Compared to rest of the Grado range, the PS series sound much less mid-range heavy, though they still have a touch more than some more clinical sets, which gives them that little bit more exciting a sound. As for other competing headphones of the same price, well there aren't all that many that exactly match the PS500.
There are plenty at around the £200-£400 mark and at £800 (Sennheiser HD800 for instance) but there are only a couple of sets at £650ish. These include the Audio-Technica ATH W1000x and HiFiMan HE-5LE. The former of these is closed-back, so something of a different kettle of fish, while the HiFiMan set are high-impedence so simply won't cut it being driven from an mp3 player, though otherwise they are excellent and arguably a better choice if most of your listening is classical. Also both are more comfortable than the PS500.
The Grado PS500 are an exceptional-sounding set of headphones. Their flat, un-coloured sound makes them ideal for audio mastering as well as relaxed home listening. Highs, mids and bass are all delivered with the same detail and clout so it's just down to the track to make the sonic decisions. They're not a versatile set, with a chunky open-back design, but you can at least drive them using a normal mp3 player, and for their price they offer among the best sonic experiences available. However, Grado's insistence on utilitarian design means these aren't the most comfortable, and you don't even get a jack adapter in the box.