There's a bit of confusion between the Streetly tape library and the Markus Resch library.
http://www.mikedickson.org.uk/tron/ shows:
M300 strings "A" (two violins in unison)
M300 strings "B" (solo violin played very gently)
http://www.mellotron.com/soundframe.htm shows:
M300 Strings "A" (cello,viola,violin 3 way split)
M300 Strings "B" (ala Barkley James Harvest) ?
The tapes that I have for M300 strings sound like two violins in unison. I've been calling them strings B but I will start calling them strings A. (You can call me Ray, or you can call me Jay, or you can call me Johnny or you can call me Sonny, or you can call me RayJay, or you can call me RJ… but ya doesn't hafta call me Johnson!)