I had the HD 555's previously and I wanted an upgrade. Had been very happy with Sennheiser so I decided to stick with them. These were a very noticeable upgrade of my previous set and they were totally worth it.

I was a Day One iPhone adopter, and can easily say that I'd buy one again, even though the first generation iPhone is clearly not perfect. My main complaint with the iPhone is the battery life. Compared to other cellphones, the iPhone's battery life can best be described as "barely adequate.

The set produces good bass, but lacks the features of other models.

Comprehensive sound and soft ear cushions make these headphones easy to wear all day

The lack of features is frustrating; and the open-ear design hinders noise isolation

Source: Lite-On DVD Combo Drive Audio CD's Headroom Ultra Desktop Amp with Max DAC USB from computer into mini USB on Amp / DAC Music: Cake ( Motorcade of Generosity ) Great vocals and right to left motion within the sound field Cake ( Pressure Chief ) Especially \"Wheels\" Awesome bass lines,...

The Sennheiser HD 650s are a set of high-end, open-backed, over-ear headphones. The HD 650s implement their open-backed design in an aesthetically interesting way, covering the backs of the ear cups with a grey grate which offers barely any physical barrier between your sound and the world around...

You can tell these hardy Sennheiser veterans mean business. Metal construction gives a vice-like fit on your dome and speaks of their ineffably high-end sonics. You'll need an adaptor to plug them into an iPod; these are built to be part of a nice little home hi-fi set-up.

Sound is flat-out the best here; Across a full gamut of musical styles the HD 650s serve up smooth, subtly conveyed sound, but when you want them to kick out the jams, these metal mothers don some large-style boots.

The open-backed design leaks sound like a sonic sieve, so these are totally unsuitable for wearing on the tube, unless you enjoy "chin music" courtesy of your fellow passengers; Given that they're thus intended for long, immersive home-listening sessions they could also be more comfortable.

Yes, I would recommend this to a friend

Good Bass; Great Sound

Uncomfortable

I was looking for a noise canceling headphone, however, it didn't work at all. But the price is the best I have ever see for hd650.

The HD-650's are incredible headphones. They are entirely musical, and that is the very best compliment I can give them. I can wear them for hours, and they are physically comfortable, as well as easy on the ears musically. They are very detailed, but not in an obvious, contrived way.

Unbelievable clarity; very transparent; flat frequency response; very musical and detailed

Almost too transparent to source, AC power, and wiring; Absolutely requires a good headphone amp

The desire to maintain domestic tranquility motivated me to start listening to music through headphones more often. My 30+ year old AKG K240s have served me well but I thought it might be time to audition something new.

Quality product, great sound; I found the 650s to be comfortable over several hours of listening

Now I think I'm going to have to upgrade my CD player...and then a new integrated amp to take full advantage of the 650s