The HP-800s' sound is nicely detailed and airy, and the stereo imaging is spacious. As noted, these headphones play all music genres equally well.
I compared them with Audio-Technica's highly regarded ATH-M50 headphones, another "monitor" model that also costs around $150.
The M50s' sound is slightly more transparent and detailed, whereas the HP-800s' is more laid-back and richer. The HP-800s' bass is a little more powerful, but the M50s' low end is clearer and better defined. On recordings with acoustic bass, each bass string pluck was more distinct over the M50s. The comfort level is similar, and both headphones are extremely wearable over long periods without rousing listener fatigue. There's no clear winner here, but if you care more about bass oomph than clarity, go for the HP-800 headphones.
While the HP-800 and M50 are closed-back designs that seal off the listener from the sound of the surrounding environment, I wanted to compare the HP-800s with an open-back design, and I went with the Grado SR 225i headphones. These two models sound very different, and the open versus closed aspect of the designs wasn't the main story (though the SR 225i headphones do let in a lot more sound). The SR 225i headphones have a much brighter and more detailed sound than the HP-800s, and the SR 225i pair makes a lot less bass. There's an undeniable immediacy to the SR 225is' sound, but I suspect most people will prefer the bassier HP-800s.
All of my listening tests up to this point were conducted with the headphones plugged into my iPod Classic, but I watched "The Dark Knight Rises" on my desktop computer, with a Schiit Magni USB/DAC headphone amplifier. The HP-800s' plentiful deep bass provided a solid foundation for Hans Zimmer's ominous score and chief bad guy Bane's booming voice. These headphones' sound is well suited to playing movies.
The NuForce HP-800 headphones are ideal for buyers seeking great sound, high comfort, and rugged construction for a very reasonable price. The HP-800s' bass is unusually potent, though definition is a tad soft. Granted, this model is not a looker, it lacks an inline remote/mic for cell phone calls, and it may be too large to commute with. However, I think that's part of the HP-800 model's charm. It's not trying to be all things to all people. You have to take it on its own terms -- or not.