Many, many sources of noise are everywhere, and each of them can render any of these 60 seconds of IR recordings unusable (wind, birds, planes, passing cars or people ... you name them). OTOH, listening for 24 hours or more to sine sweeps in concert volume (85 dB in a free-field measurement!) is hard for _us_ --- but it's intolerable for any creature in the neighbourhood, be it a human or an animal.
Point taken! Let's hope that they find ways to make this more environmentally friendly anytime soon.
As for possible locations: Something like Schloss Kremsegg or Schloss Hof (as far as I know they do concerts as well as balls) would fit late Renaissance and Baroque instruments. The great hall of a "Burg" type castle would be interesting for soundtracks though there's none in Lower Austria that exactly leaps into my mind.