The Chicago/Philly/Boston Gabrieli set is required listening for brass players (or should be).
Definitely not small ensemble playing, but it's some of the best you'll ever hear. And E. Power Biggs brings the organ stuff, too.
SD
I am convinced that 90% of the problems with rhythm, tone, intonation, articulation, technique, and overall prowess on the horn are related to air issues.
Aforementioned recordings are absolute essentials. Both Canadian and Empire have done fantastic Gabrieli-Monteverdi antiphonal recordings with great symphony brass sections that sound unbelievable on the Hi-Fi.
Also, consider the catalogues of the Philip Jones Brass Ensemble, New York Brass Quintet, The American Brass Quintet, The Annapolis Brass Quintet(the first full time quintet),
The St. Louis Brass, The Summit Brass, The Los Angeles Brass Quintet, The Chicago Brass Quintet, Chicago Chamber Brass, The German Brass, etc. All first rate ensembles, most with vast catalogues of great music to choose from.
At the 2007 USABTEC, free CDs were given out of an Air Force quintet with organ. The name of the CD escapes me, but I'm sure someone has a copy laying around. It featured new and arranged music for quintet and organ.
The Pittsburgh Symphony Brass have a recording of THE ART OF FUGUE by J.S. Bach that is one of the best brass recordings of all time. A truly symphonic approach to the piece that I've never heard before, except when the Chicago Brass Players performed it back in 1992, with George Vosbourgh, Neal Bernsten- trumpets, Charlie Vernon on tenor trombone, a hornist from the Chicago Lyric Opera and Rex Martin, tuba. Best brass concert I've ever attended to this day.