That's the problem. I don't recall the cm10s (that was three years ago), but I did notice a difference with the newer 702s. However, I didn't want to pay that much money again. I've had the 704 s2 for a few days and think they sound great, but I can't help but think I could have all of that for less than I paid for the two 704s... The other point about which I'm concerned is the warranty.