Yup I loved it too... after a few hours things just seem to really brighten up at these meets. Without further ado...
Here's my top picks (no particular order):
AK240 with DT 1350
This combination completely blew me away! The sheer amount of sonic goodness rushing out of my DT 1350 like a pack of raging bulls! I couldn't believe it - after 4 years of owning these on-ears and trying it with at least 10 setups, this is finally the solution for it's subpar performance on everything else prior: super lifelike and cohesive 3D soundstage, impactful, great imagining, etc... unfortunately it's an un-atainable price for me at about the same pricetag as the Yggy
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speaking of the Yggy...
Yggdrasil / Rangarok with HD 800
This combo instantly struck me with astounding realism. The first thing that came to mind was that this is around 70% of a SR-009 if on a good amp. This really does reveal 'plankton', as they call it, and in a good way. Micro detail galore, fast PRaT, and arguably the best soundstage. Still slightly lacking in bass quantity.
KGSS with Bifrost and Stax SR-009
The sound that came out of this setup was absolutely electrifying! Up there as one of the best audio experiences of my whole life! Absolutely glorious and phenomenal, refined sound: As much fine details as you could ever want, spot on imaging and dynamics, tonally correct and pleasing midrange, and amazing frequency response! Not to mention the quality and speed of ALL frequencies. No wonder this is widely regarded as an unwavering champion, only to be outdone by the Orpheus at around 25x more the cost. The only downside is that the bass maybe be ever so slightly recessed, but the overall package is so fantastic that it's hard to notice.
Also trying the SR-009 on the Stax SRM-1 MK2 amp, I was very underwhelmed, seeming underpowered, smaller soundstage and everything that was good above reduced by a factor of 2
Also trying another SR-009 on the Blue Hawaii amp, I was impressed but for some reason it didn't strike me with quite the otherwordly experience as with the KGSS setup
note: anybody who's interested to know more such as the exact model of amp / DAC used on the above amazing setup can contact @manywelps
M903 amp/DAC with ATH-R70X
Another truly glorious experience!!! I guess my impressions on the first page were just a preview, because here's the real deal:
OK to start out, what these headphones, especially with this combo do well is mids, mids, and ohhhh yessss, mids!!! And it's done in a way that is not mid-centric either, yet the entire FR (frequency response) is superbly linear. But the reason I mention mids three times is because the way it handles them mids is just totally surreal - borderlining paranormal! Those mids are spine tingling and oozing with lushness that really smack you on the cheek in a way that you can almost feel it. Listening to some of Michael Jackson's top tracks I had an MJ experience unlike ever before - and it's said to be great for vocals especially. But not just the mids, the treble and bass quality were superb! The soundstage was excellent too. My only gripe however, is that the bass is fairly lacking in quantity, so I recon these 'cans would need a fair amount of EQ'ing or possibly even modding to please most electro or pop fans.
I also tried the ATH-R70X on the Headroom Balanced Ultra Desktop Amp with Bifrost 4490 and I would say it also sounds grand, but the synergy was not quite the same. The lushness and dynamics seemed reduced by perhaps about 15%, but all else remained wonderfully present.
I also compared the HD 650 the the R70X on both the same amps, and I actually still prefer the HD 650. The mids were gloriously present / vibrant / lush just like above, slightly recessed treble and improved bass quantity, and the impact was equally good IIRC. The soundstage seemed just as large, but more 'correct' as it seemed more 360' as opposed to having more perceived height than width on the R70X. And the slightly recessed treble can be really a good thing when it comes to reducing listening fatigue.
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Eddie Current Zana Deux versus vintage amp (Mcintosh MAC 4100) and Gumby DAC with HD 580 or 650
Zana Deux pairings:
Perhaps this is my #1 favorite setup of the day. Even though the SR-009 is dreamy great, this one has better bass quantity and being SE topology, is compatible with standard headphones. And boy do these ever make a good headphone sing! What you get is super amazing refinement all across: a soundstage 'worth writing home about' that is as large as can be imagined, and done with super realism and cohesion, instrument separation that is uncanny good and also cohesive, excellent details (though not quite as much with the above Yggy / HD 800 or SR-009), phenomenal impact, great FR extension on both ends, and a very 'musical' sound overall.
Vintage amp pairings:
It seems that everything mentioned above about the Zana Deux, this vintage amp does almost the same. Notable exceptions would be that the bass quantity is slightly better on this amp, and being a SS, this doesn't have that euphonic tube saturation. This can be a good or a bad difference, depending on the particular song and the way it was recorded. IIRC, it seemed I preferred this amp more with electronic & pop, but the ZD amp better for analogue-ish recordings like rock. It's uncanny the level of energy, detail and bass quality this old receiver has!