Please don't sell your 600 for the 660. . 95, and the cost of the Sennheiser HD 650 is a bit steeper at $549. Exactly as you said. . See if you getting enough volume. . The Sennheiser HD 650 are slightly better audiophile headphones than the Sennheiser HD 660S2. Well, Massdrop is at it again, this time with the iconic Sennheiser HD650. AKG K240 vs Superlux HD 681? Does anyone have experience or can recommend any of these two (semi) open backs? How are their imaging/ soundstage, quality of sound and tonal balance? 5. The HD650 beats out the LCD-2 in most areas. I get how some prefer the HD650 over HD600. . Which is great, but for fun I usually prefer speakers, so I found little use for the Senns, and sold them. The headphones’ cable is 3 meters long (just under 10 feet), which can be very cumbersome. I bought it for the reason that it is nearly impossible to make it sound bad. The AKGs definitely have more sparkle/emphasis in that region, while the Sennheiser's midrange is infamously 'veiled' because of poor separation between the upper bass and midrange. . Pretty resolving and great timbre and tone. . . One step forward and one step back,. . . But first, I should start off saying they both sound very similar. . I can't seem to make my mind up between the HD600 and HD650. . The 660s is not as dark as the 650 and has the best imaging in the family. . The 600 has better resolution overall, more forward mids, and due to its higher impedance drivers, better scaling with equipment at the cost of some drivability, the 600 is dark/warm. Gaming. The biggest difference is how they feel once on your head. . ago. Awesome, this is more or less the answer I was looking for. Yes, the HD660S2 sounds objectively better. 110dB on the 560S is actually very high, and 91dB on the 400SE is pretty low. . I own the 650, both are great headphones but not the last word in resolution, the 660S is a bit easier to drive though (150 ohms I think. HD650 has a more involving, tonally accurate sound. . Sensitivity determines how hard a headphone is to drive. The 560S also has somewhat more treble and harshness depending on the listener then the 6XX/650. . But, they are much better with EQ. . 3- The hd600 has a better FR, and Crinacle based his judgment on that. . The treble response of the HD600 exceeds the HD650 in the graphs, but I'm more interested in real-world results. . 95, and the cost of the Sennheiser HD 650 is a bit steeper at $549. I get how some prefer the HD650 over HD600. HD660S has excellent imaging/separation (for music), more punchy bass, more dynamic. AKG K240 vs Superlux HD 681? Does anyone have experience or can recommend any of these two (semi) open backs? How are their imaging/ soundstage, quality of sound and tonal balance? 5. I've heard both the Sennheiser HD600 and ATH-R70X. . . . It's easier to drive, great for gaming, and decent for movies. Fast forward a few months and I decide to buy the DT880 600ohm version. Same with the K612 vs the K701/K712 Pro. . Also, the new HD600 and 650 just come packaged in a cheap cardboard. .