I am in fact looking for an alternative to the HD800, and am more than happy to free up some cash selling the SR009. From what I read the HE1000 is a manned up version of the SR009. I guess you can't have ethereal and fast sounding decay together with hard-hitting impact.

Exactly. HE-1000 has testicles. Those expecting 009 transient response will not get it, but HE-1000 comes closer than anything else before it. Only my uber cherry picked Audeze LCD-3 that lasted less than 24 hours before breaking equaled the HE-1000's speed.

It's just like speaker drivers. Speaker drivers have a window of optimum usability. Some can do treble well, very smoothly, but strain in the mids and explode if asked to do bass. Others do good in bass and mids, but break up into harsh sound in the treble. Others concentrate on a wide range in the mids but suck at lows and highs, etc.

There's no free lunch. However, the HE-1000 is unique in being able to get such good extent of results with diametrically opposed sonic traits: lot of bass heft with very good transient response. It ain't no STAX, it doesn't have to be, and not everyone likes the STAX sound.

Most 009 guys I know, and there are several here, are pretty diehard and don't listen to much else on a regular basis. The HE-1000 won't satisfy them if they want that super delineation and transient response fix with the high hat on that Metallica recording. To me, this a good thing, because personally I don't want a 009. The 009 sounds too politely colored and artificial to me. Even the speed of 009 I find unnatural and unsettling. Don't get me wrong, the 009 does certain things extremely well - so well that nothing else matches these certain things. I've considered repurchasing the 009 as second setup several times; but every time I hear one, I always think "I guess I'm not missing much - just not worth the hassle."