Sony enters a dangerous field with the MDR-xx. Around this price is where headphones start to get really very good. Unfortunately, they don’t manage to challenge the best of their rivals.
We can’t pick out a particular sound signature Sony is attempting to create with these earphones, but that’s not necessarily a bad thing. The best earphones strive for balance and neutrality, in turn fostering excitement and musicality through the strength of their delivery. The Sony MDR-x put their feet in some of the right places, with well-mannered bass - where the low-end is still so often out-of-kilter even at this non-budget price. The Sony MDR-EX510LP's bass is more balanced than the Ultimate Ears 400 and AKG K350, and detail is well-articulated lower down the frequency spectrum.
Our issue is with the Sony MDR-EX510LP's treble. It's harsh and invites sibilance in a way that accomplished rivals don't. Ultimate Ears 400 are arguably even more treble-focused but offer a much smoother high-end that also comes with none of the artificial-sounding serrated edges heard in the Sonys.
This nasty side-effect of the flawed treble doesn't show up in all kinds of music, but is particularly prevalent during any poppy histrionics. The vocals of the flamboyant Patrick Wolf and the flouncy Friendly Fires can sound as if they're accompanied by the wails of a screaming baby, for example. When this effect enters stage left, your ears won't thank you for picking the MDR-EX510LPs.
We should note that note all high-flying earphones are masters of the high-end either. The Shure SE215 roll off at the top end, and the AKG K340 aren't without a hint of artificiality. These earphones' brittle-sounding upper register is only highlighted by the rest of the sound though, which is lean. Other pairs can half-mask a serrated treble with expansive bass or a warm mid-range, coating potentially-sibilant instruments like violins and the human voice in a sort of sonic goo that mitigates for the figurative spiky hair cut up top. Like a mohican'd punk wearing an "I love Barbara Streisand" T-shirt.
It's a terrible shame too, because if there was a little more smoothness up top, the Sony MDR-EX510LP could compete with the best in this class. As it stands though, they're destined to become an also-ran until one of the major online retailers does common usual trick of selling them at a ridiculous price. The over-egging of treble is often harder to forgive than overdoing the bass a bit, simply because of the different sort of strain they put upon your ears.
The Sony MDR-EX510LP come close to offering great sound for the price, with balanced, tasteful bass and a fairly wide sound. But all that promise is spoiled by treble that all-too-often harsh and sibilant. For the same price, you can nab yourself a set with an equally-detailed sound that's much easier on the ear.