My own review of this Penderecki disc, written about in his usual erudite
fashion by Steve Schwartz, can be read at

   http://www.amazon.com/exec/obidos/ASIN/B00009XBJ8/classicalnetA?

Here is its first paragraph:

Can you imagine a direct line of descent from Schubert to Mahler to
Shostakovich to Penderecki?  Yes, at first thought it seems unlikely.
But the main piece on this disc--at 32 minutes it takes up almost half
of the CD's playing time--the Sextet for Clarinet, Horn, Violin, Viola
and Piano traces a trajectory that makes this descent fairly obvious.
The first of the Sextet's two movements, the Allegro moderato, begins
with a tramping low A-flat ostinato from the piano that suggests a young
fellow setting out on a walking journey not unlike that of Schubert's
hero in 'Winterreise.' His thoughts and comments are primarily expressed
by the two wind soloists in the sextet, the clarinet and the horn.  He
starts out rather naively and with bumptiously optimistic horn tunes but
soon begins to make increasingly sarcastic comments; to accomplish this
Penderecki uses the clarinet in its highest register, a technique pioneered
for this very purpose by Mahler who often pushed the notion to its limits
by using the wailing of the even higher E-flat clarinet.  Of course,
this is one of the Mahlerian traits that Shostakovich made such effective
use of in his symphonies and operas.  The movement winds down a bit,
although there are weak attempts along the way to express the young man's
high spirits.  These attempts become as hysterical as they are hopeless,
as if the protagonist knows his efforts are in vain, that the world's
woes will beat him down.

Scott Morrison