OK, here's a mini review for all those who are interested in these headphones but don't listen predominantly/ mostly to hip-hop.
I listen to quite a few different genres, so I thought I'll add my 2c. I got interested in the JVCs because I wanted to add a good bassy headphone to my collection, I have some very good headphones which I thoroughly enjoy, but none of them have that real thumping bass that I want every now and then. I stumbled across this thread, and the curiosity-to-price ration was enough to let the curiosity win and I ordered these from amazon.
Listening setup: At home: Laptop -> Tubemagic D1 dac -> Meier Audio Corda Concerto. On the go: ipod -> v-moda Vamp Verza.
First listen out of the box with stock pads, I was surprised that these sounded quite nice throughout the scale. Once I played around with the pads, the HM5 pads were deemed the best fit (Alpha Pads slightly too big and don't form sufficient isolation, 770 pads too firm for my taste).
These headphones are really great at giving you a feel for the bass. I have other headphones in which the bass is very articulate, yet doesn't really kick very strongly. On the ATH-W5000 and the Alessandro Alumod/ MS1000 (modded MS1), the bass is very articulate, but really lacks any true punch. It is like admiring it from a distance. Both of these headphones articulate the highs beautifully, and in that department, the JVC has little to offer. The JVC's still have some sparkle in the highs, but overall, the mids and highs are quite veiled, and a bit grainy. Even my darker sounding headphones (Mad Dogs 3.2, HD650) still have clearer highs than the JVC's.
These are definitely dark-sounding headphones. Listening to these headphones really feels like listening to a concert in a club with a really good sound system. The bass is full, rich, and pumping (on properly recorded tracks). The club is dark and smokey, so you can't see the band on stage very clearly, but the sound is very immersive.. and really, who can concentrate on the fine details of the music when you're dancing and having a ball?
The bass... it's fantastic. It gives a new dimension to it, which is often missing in other headphones. On these, I mostly listen to rock, funk, and soul. These headphones are great at revealing good (and bad) music engineering - they can really reveal whether the bass is recorded properly or not. Before getting these, there were some songs/ albums that I was particularly looking forward to listening to - and some of them disappointed, as it was revealed that their bass isn't recorded well enough to produce true punch from these headphones. Some other albums however surprised with the power and quality of their recorded bass.
Here are some examples of rock/ funk tracks which I think bring the best out of these headphones. Please note that, for best impact, listen to a high-quality source rather than the youtube links below, but these would give you a rough idea:
Aerosmith's Living On The Edge has some very good quality bass sound, the drums really kick throughout the whole Get A Grip album. On this song in particular, around the 3:30 mark, there is a real thunderous sound of drums that I always use to test the bass limits of headphones. Some headphones fail miserably at this test - the JVC's are marvelous at this, the whole headphones vibrate and the sound is huge.
Parliament/ Funkadelic are what I listen to more than anything on these headphones, for a complete club-like feeling. My idea of a party, and these are definitely party headphones. This track is also good to showcase that the JVC can even have some nice sparkle on the highs on the right track.
The Black Crowes' Virtue & Vice has very nice thunderous intro, which is another track I use to test bassiness of headphones.
This recording from Humble Pie is just spectacular, and is probably the only track here that sounds better on this particular youtube version than the album version (the album Eat It is quite controvertial due to its sub-par sound recording - which is very unfortunate, as it has some truly great music). Bass player Gregg Ridley is featured here.
The Who - Live At Leeds album. Features perhaps the bass bass/drum duo in classic rock. This album might be my favorite sounding live album, and the bass just sounds truly spectacular with the JVC's. You can just focus on John Entwistle's utter brilliance.
To conclude, I would definitely recommend these as a special-missions headphones for all people who enjoy some bass every now and again. Personally I disagree that these are strictly for hip-hop, but keep in mind that these will reveal which albums recorded their bass properly and which didn't. I wouldn't recommend them as your only set, but would strongly recommend them as a party headphones for those who, every blue moon, have ants in their pants and they need to dance (in the comfort of their homes...)