You can hear some of this kind of playing by the fabled Portsmouth Sinfonia. This was a truly amateur orchestra – amateur in that they loved (ama) what they were doing, and amateur in that any musicians actually in the orchestra didn’t play their own instruments. If you were a pianist, how about a flute? Or a clarinet? You had to be sincere, however, and not perform with humour. This was music, strained heavily through the lack of technique or anything else.
The composer Brian Eno joined the orchestra as a founding member and clarinetist and was instrumental in getting the ‘worst orchestra in the world’ signed to Transatlantic Records, also serving as producer on the first 2 albums. Their last album in 1979 (20 Rock Classics) was on the Philips label.
Of course, by the end, having played so much, they actually could play better, to a degree, and that somehow took the edge off their edginess.
Bryars: Jesus’ Blood Never Failed Me Yet: III. – (unknown voice; Hampton String Quartet; Michael Riesman, cond.)
As a piece of both music and concept art, it has a strange calming fascination, even today.