I'm mostly familiar with ECM from their jazz offerings, but Manfred Eicher is legendary for spending an hour and a half positioning a single microphone to record Keith Jarrett. Their early recordings of artists like Keith, Chick Corea, Ralph Towner, Egberto Gismonti, & Jan Garbarek are among the most important reasons I began this pursuit. More important than the fabulous sound quality, the music itself ranges so far & wide that neojazzical seems a more appropriate label.
Naxos is another label with range, but with a focus on classical. Within that genre, they produce a quality discount product while still being able to go outside the "standards" repertoire, recording with less well known conductors, orchestras, & soloists. Of course, being less known is not the same as being less. Their success has demonstrated that, for both the music and the musicians.