Sennheiser Consumer Audio HD 660S2

Got these cans for 400 dollars for black Friday. SOUND: These headphones sound better to me than the rest of the 600 series simply due to their better sub-bass performance. They have a pretty wide soundstage, have excellent instrument separation and sound good with all music I have thrown at them. The mids perform excellently, just as the rest of the HD600 series, and the treble is sparkly and nimble but not fatiguing. These are a good, balanced, warm sounding pair of headphones that are well worth the price that I bought them for, however I could not recommend these for $600 as this price forces competition with a higher class of headphones. COMFORT: These headphones are the most comfortable pair I own, with nice soft earpads and a perfect amount of pressure that gets a good acoustic seal over my ears. My head is on the larger side, so as to the issue of clamping force, I really did not feel that they clamped too tightly. These are the kind of headphones that I could wear comfortably all day and forget I even have them on. DRIVING EQUIPMENT: To those that have mentioned an unimpressive performance from these headphones, when used without a headphone amplifier or properly specified piece of equipment, these headphones tend to sound a bit soulless, empty, or a bit muddy. However, the great thing about the HD600 series is that they tend to scale very well with good sound equipment. The difference in sound that an entry level Schiit DAC+Amp stack made was well worth it and really made these phones come to life. This does mean, however, that you should also consider the cost of an amplifier and DAC unit as a cost included with these headphones, so at minimum another $200 added onto the already expensive price. There are many other good options for headphones that are easier to drive and do not require a dedicated amp for this price range, so if this isn't for you, I would look elsewhere. Overall a great sound albeit a bit overpriced at MSRP.