room for:

[RobbieD]

what kind of room do you need for:
upright piano
horns(saxophone)
acoustic guitar
strings (violin)
vocals

more dead or reflective?

 

[mixsit]

Nice sounding reflective form a large enough room.
Some control of reflections from said nice room.
More control if the room ain't so nice.

I could see guitar, voc, maybe horns wanting to be recorded either way.

 

[MG Eddie]

It is also going to depend on how you chose to mic anyone of these instruments. If you chose to use a mic with a shotgun pattern then you'll have more overall control of just that one sound and less interference from the room. Also your mic placement will reflect the kind of room you use or in which part of the room you chose to use. I.E. the corner vs. the center or just one side.