Grobschnitt are one of the all-time Krautrock greats. Their first run of albums, up to and including Jumbo would be mind-blowing in Atmos. Especially their debut. Some of that weird German humour can be a bit distracting at times, but they're playing to a German audience here, who would be right at home with it, and there's not too much of it to distract from the amazing groove.
Other incredible Krautrock bands with a strong prog bent include Guru Guru, Amon Duul II, Triumvirat, Faust, Ash Ra Tempel, Thirsty Moon, Kraan, Cosmic Jokers... who would also be well suited to Atmos. Others too, just can't think of them atm (of course there's Can etc, but I'm referring to the more proggy Krautrock bands). It's always amazed me that these bands haven't had the same 5.1 and now Atmos treatment as we've had for many the British prog bands. This is very welcome indeed.
1970's Krautrock is the biggest can of worms possible for multi-channel resurrection (well, certainly Italian also)! Trouble is these artists were unkown except to us extreme progrock "propellerheads" who were willing and eager to pay a couple bucks more for some of those deliciously exotic import LP's back in the day! (All now prized collectors' items for those of us who retained them!)
Add to that the reality that I was earning maybe $5 hourly working full time, and had to pay $150 monthly rent, plus everything else along with an occasional bag of weed, and I just wasn't able to buy all the cool international prog that was being blasted out like a firehose throughout the late '60's/early-to-mid '70's.
I knew of Grobschnitt, and was intrigued by what I was able to hear, but they just had to be triaged because I COULDN'T buy everything.
Oh man, what would be my dream Euro Prog reissue, then? Triumvirat YES, but only "Spartacus" & "Illusions," Amon Duul II "Vortex," Kraan "Let it Out" or maybe "Wiederhoren," Nine Days Wonder "Sonnet to Billy Frost," Klaus Schulze "Mirage," Kraftwerk "Trans-Europe Express" or "Man-Machine" ("Autobahn" WAS released on Q8, but never LP, alas). I'm sure other quad fans can name hordes of others I would automatically agree with, but I gotta keep this post somewhat concise.
Other Euro-faves I'd love to see: 5.1+ reissues of: Wigwam "Dark Album," "Nuclear Nightclub," or "Lucky Golden Stripes & Starpose" (Finland), Italians PFM "Chocolate Kings," "Per un Amico," "The World Became the World," Le Orme also had SEVERAL more than worthy releases but were somewhat handicapped in that they only sang in Italian. Here again, other readers are encouraged to chip in your own faves, many of which I'd agree with instantly.
There was some quad activity during the '70's in Europe, of course. I have the "Dark Side of the Moon" on UK Harvest SQ quad, plus more obscure items like Nektar "Down to Earth" (not their best album, alas) on the German Bellaphon label. I know Nine Days Wonder had a quad LP release for "We Never Lost Control," their so-so 3rd album, and some early Tangerine Dream had quad releases, "Zeit" and "Alpha Centauri" that I know of for sure on the Italian PDU label. Mike Oldfield's "Tubular Bells," "Hergest Ridge," & "Ommadawn" all got UK Virgin all got UK quad releases, and IF memory serves, the "Mike Oldfield Boxed" collection of all 3 '70's hits were quad versions.
I'm just shooting from the hip here, and I don't pretend to know what the full spectrum of '70's prog that got quad release ultimately was. Modern multichannel remixes would be welcome BUT the same economic dilemma of the '70's reasserts itself: now these lovingly-curated "50th Anniversary" editions emerge, but I'm a retiree & can't afford everything at $50 a pop. I gotta be grateful, though for the STEREO LP's I had the means & wits to buy & hold "back in the day."
one and all .
i had it in my Library as well and even though it's still in there all the songs are greyed out and unavailable and the alternate version is streaming in Stereo only! 
bah humbug Apple!! 
