HEADPHONES!!!!

[drewhaynes]

They are lower impedance but to me they sound great.  The Audio Technica ATH-M50x is currently my fav with the Sony MDR-7506 running a close second.

Can't argue with that I owned a pair of M50 (non-x I wanna say) a handful of years ago. Pretty good closed cans.

I wish Beyer was still making the 600ohm DT770, instead of just going up to 250ohm. My wife would love it if I got a pair of closed headphones for when I'm up and she's going to bed in the next room!

[mcandmar]

The original HD-800 did have some frequency quirks that didn't suit many of the upgraders from 600 and 650. Senn have fixed that I believe with the S model but it is more dollars. Some claim to have fixed the problem themselves with a range of mods but it's an expensive risk.
Have a browse here. Yes it's one man's opinion but he really likes the Crack, and has built one, so that's a good start!
https://www.youtube.com/user/InnerFidelity/videos

Yes/No/Sort of.  There is a long thread on Headi-Fi discussing the frequency response plots from various serial numbers (you can request the test results from Sennheiser).  Generally speaking some of the early serial numbers had a spike ~ 6khz which made them a little harsh which was dialed out on later models.  You can also see a trend towards slightly higher low end response with the most recent models.  Its a bit hit and miss with some better than others, i got lucky with mine as they have a very flat EQ with no 6khz spike, and they are very early with a serial number in the 1300 range.

As for the above, buy a pair 2nd hand, you will never need another pair of headphones ever again.

[adydula]

The Beyer 250 and higher impedance headphones work very, very well with the Crack....either the T90 or several of their other HP's would fit the bill nicely.

The T90's are brutal in exposing bad recordings with the Crack...

The T1's are very musical and exacting as well....

$400 vs $800+...found on sale etc..

Alex

[attmci]

Yes/No/Sort of.  There is a long thread on Headi-Fi discussing the frequency response plots from various serial numbers (you can request the test results from Sennheiser).  Generally speaking some of the early serial numbers had a spike ~ 6khz which made them a little harsh which was dialed out on later models.  You can also see a trend towards slightly higher low end response with the most recent models.  Its a bit hit and miss with some better than others, i got lucky with mine as they have a very flat EQ with no 6khz spike, and they are very early with a serial number in the 1300 range.

As for the above, buy a pair 2nd hand, you will never need another pair of headphones ever again.

Do the mod and use a black dragon cable will smooth the 6khz spike. It works great with Crack.