So I got a pretty good deal on a pair of refurbished HD 650 this week and picked them up for $280. I got them today, and love them, but I feel like my HiFiMAN EF2A is the weak part of my setup. It makes the 650 sound nice, but not even close to as good as I know the 650 are capable of (not to mention it's pretty noisy/hissy). I talked to Mike of Headfonia, Austin Morrow, and a couple of other head-fiers, and the general consensus is that the Bottlehead Crack is going to get me the best bang for my buck.
My question is that, on their $220 amp, is the $100 Speedball upgrade worth the extra dough? I'm really big on a black, quiet background which Bottlehead advertises the Speedball upgrade remedies. Additionally, I can't help but be interested in their additional $60 power cord kit, albeit very skeptical. I know they're pretty forward proclaiming that they don't know what makes it sound noticeably better as well as quieter; however I'm wondering—for those that have opted in—if that's also with the extra dough.
Last, but not least, since I'm ditching my EF2A which I'm also using as my DAC, what's the cheapest USB DAC I can find that won't tamper with the rest of my otherwise flawless setup? Thanks everyone.
Edited by TSIG - 2/3/12 at 12:22am