Coming from the classier end of JVC's headphone line-up, the JVC HA-S600 avoid being tarred with the "XX bass" brush that has attacked other JVC sets. You wouldn't know from listening to them, though, because the low-end is more dominant here than in many unashamed bass-heavy pairs.
The bass here is an ill-defined fog that resonates unhelpfully over the rest of the sound, clouding detail and robbing music of clarity and impact. As the bass swell is so wide-ranging, rather than limited to the lowest frequencies, it doesn't even give much impact to the beats and kick drums that can benefit from a bassy style. Poorly controlled and without any remarkable depth, the low-end is downright poor.
Treble performance is better, but not by a great deal. There appears to be a spike, followed by roll-off. This may equip treblier elements with the weapons they need to avoid disappearing entirely into the bassy fug, but it doesn't lead to a very even or balanced sound, and supplied presence without notable detail. Vocals may stand out enough, but they are not well-resolved.
And, as is common in budget headphones and earphones, the midrange is relegated to the subs bench for the most part, its role instead played by boomy bottom end.
The JVC HA-S600 are a disappointment. After enjoying their simple, unadorned look, we weren't expecting them to sound as brat-like as the most urban "swagger down the high street with my trousers falling down" high street-bound sets.
The Sennheiser HD 202 may not have the interesting look of these headphones, but they do provide much more even sound quality. And if you're not desperate for an over-ears design, there are plenty of great on-ear choices available around the same price. The Koss Porta Pro and Sennheiser HD 220 get you better sound for around the same price.
With an interesting, classy-enough look, the JVC HA-S600 headphones had us interested instantly. And, although not supremely comfortable, their lightweight and foldable design should make them perfect on-the-go cans. It all goes a bit awry once you put them on, though. Overblown bass and poor definition ruin the party.