In its nearly five-year existence, the Paradigm Trio has been developing a solid repertoire of works for the piano-trio medium.

That's an impressive accomplishment, given that the Paradigm is not your typical piano trio. Minus a cello, but with a viola, this particular makeup doesn't have a tailor-made repertoire, but that hasn't stopped the threesome from pursuing the literature.

Only a few composers have written for piano/violin/viola. Besides this meager collection of scores, the group has a stack of works arranged from the standard trio format.

"We have about 12 or 13 trios now in our repertoire," said Joel Rosenberg, the group's violist. "And we keep adding more to our list."

Rosenberg and his trio colleagues Kelly Parkinson, violin, and Jed Moss, piano, will present the first of two pairs of concerts next weekend in the First United Methodist Church.

What will make the concerts unique is that the ensemble will give the local premiere of Brahms' two string sextets in an arrangement for piano trio. "To the best of my knowledge, this will be the first time that the two works will be played in Utah in this version," Rosenberg said. Both sextets were arranged for trio by Theodor Kirchner, a composer who became one of Brahms' closest friends. "They met in the 1850s and became good friends."

Kirchner arranged quite a few of Brahms' works. In particular, the piano-trio versions of the sextets were among his most successful. Brahms praised them, saying that they bring pleasure to anyone who hears them — high praise from a composer who was self-critical to a fault.

"These are wonderful additions to the trio literature," Rosenberg said. He added that this is a new way to experience the music. "As trios, this is a whole different way of looking at them. But they work very well as a trio."

For the Paradigm Trio, the two sextets underwent another transformation. Kelly Richardson, a violinist with the Orchestra of Sandy, arranged Kirchner's versions for viola. "Kelly has been a big help to the Paradigm Trio," Rosenberg said. At next weekend's concerts, the threesome will play the earlier B flat major Sextet, op. 18, together with Mendelssohn's Trio No. 1 in D minor. At the Jan. 28-29 concerts, the trio will play the second sextet, in G major, op. 36, along with Schubert's Trio in B flat major.

Rosenberg said that the Mendelssohn and Schubert trios, both arranged for the Paradigm by Richardson, are suitable companion pieces to the Brahms. "They are both absolutely wonderful works. The two (sextet) works are much lighter than his later chamber works, and they have a lot in common with the Mendelssohn and Schubert works.