The Austin Symphony’s season, proper, came to a close this weekend, with a gratifyingly diverse concert of contrasting works: a Mozart concerto by Venezuelan pianist Gabriela Montero, a contemporary work by Robert Paterson and a vibrant performance of Strauss’ "Also Sprach Zarathustra," under conductor Peter Bay.

Paterson (1970) is a New York-based young composer, who despite being relatively unknown, has been making headway with the grassroots support of regional orchestras, especially adventurous ones like Louisville and Albany, who have played his work.

On Saturday night it was easy to see the appeal of Paterson’s work "Dark Mountains." It’s a piece that builds tension, takes mysterious turns into the kind of suspenseful motifs that would be very much at home inside a British mystery series. Even conservative orchestras will find little to argue against here. The work was inspired by drives through the landscapes of Vermont, and the result has plenty of lyrical passages, as well as some mid-century styled American anthems in the heroic vein. Slices of dissonance added interest to this eclectic and successful work.

Concert pianist Gabriela Montero first appeared in the form of her voice, giving the pre-concert housekeeping announcement. In lieu of the dry, formal notice, Montero’s an uncharacteristically fun and funny beginning. Cellphone users, the message said, would "be deported to Minsk."

Montero arrived on stage for Mozart’s "Piano Concerto No. 20 in D Minor" (K. 466), in dress pants and a floral blouse. She is evidently quite charismatic, yet at the piano she wasn’t given to theatrics; no exaggerated hand movements here. For all its technical proficiency, Montero’s performance seemed cautious. Some notes arrived completely devoid of color. An interpretation perhaps, but not a very generous one. (lets have something from Jonathan Biss’, who played earlier this season, instead.) The result here was flashes of brilliance mixed with passages that were quite dull.

Montero became much more animated during her encore. Instead of playing a short and lyrical piece from repertoire, Montero offers something entirely different: she asks the audience to suggest a local tune that everyone knows, so she can then tease it into an improvisation. The audience sang the consensus tune — what else, but "The Eyes of Texas" — to which Montero complained good naturedly, "We had the same song last night!"

The improv itself was fun and energetic, and so were Montero’s gestures at the keyboard. The audience truly erupted when this came to a close.

The concert’s second half brought Strauss’ still-magical "Also Sprach Zarathustra." Everyone with a pulse has heard the opening movement (the much abused work opens Kubrick’s fil "2001"), well over a century later, the whole work remains extraordinary. Strauss simply had more colors on his palette than most composers.

Peter Bay and the ASO gave an expansive performance — commanding the spectacular, percussive explosions and daintily communicating the magic of the delicate finale. Strings felt especially lush.

Bay has been experimenting with the arrangement of the strings, swapping the viola and cello sections. Hi-fi obsessives, take note: I was in the balcony for the first time in a long time and the sound there seemed more balanced than just about anywhere in the Long Center. Was this due to the new arrangement, or just basic acoustics? Well, you’ll have to find out for yourself, but at the very least the violas could actually be heard above the din. (Viola jokes aside) whether this effect was real or imagined is hard to say. Perhaps we’ll find out for certain, next season.