Ramiro Arquello:

>I have all the String Quartets played by various ensembles.  But
>somehow I lost the middle and late quartets played by the
>Quartetto Italiano which was for my taste the best.

I'd like to recommend the Hollywood String Quartet.  Rhythmically
incredible, beautiful ensemble.  It's only possible disadvantage is
that it's mono (but not "historic").

Steve Schwartz