That's on Unfinished Music No.2: Life with the Lions, on Zapple Records, a LP that I actually have held on to for some reason.
"The album opens with an extended and improvised recording entitled "Cambridge 1969", recorded on 2 March at Cambridge University, before a live audience. The piece consists of Yoko Ono's vocalisations accompanied by electric guitar feedback from John Lennon. Saxophonist John Tchicai and percussionist John Stevens join Ono and Lennon towards the end of the piece."
Recorded live 2nd March 1969 at Lady Mitchell Hall, Cambridge
Personnel :
Yoko - Vocals
John - Guitar
John Tchicai - Saxophone
John Stevens - Percussion
Introduced by Yoko, she says :
"This is a piece called Cambridge 1969".
This is the very first solo performance of a Beatle, and includes John producing feedback from his guitar with Yoko doing her own thing. Her first screech lasts almost 45 seconds, and then it doesn`t get any better... screeches and feedback almost incessantly (my children were none too pleased when I played this to time it for this research !)
The other two performers listed appear towards the end of the piece, and in fact performed for longer but this was faded out.
MORE HERE and HERE
Yes, it's boring, to say the least.