The Man-Erg Trident Studios Tape
This direct copy of the original Trident master tape has recently surfaced in America. It was found by Chris Sandecki gathering dust on a shelf at his mother's house.

Chris Sandecki: "My father's bestfriend from childhood was hired sometime around late 1970 / early 1971 by the Sheffield brothers to work at Trident. His name is Jack Nelson who soon after became the first manager of Queen. The story goes that he was hired to work with the recording engineers and oversee the producers at the time. Jack came back to Los Angeles for a short visit just after getting established at his new job in London. I guess he came home to wrap up a few things before returning to England. Anyhow, my Mom and Dad went over to Jack's parents home for a visit when he was in town to catch up. Jack said he was working with some amazing new bands and was really excited about the work and that he was also really looking forward to returning because he was trying very hard to get a new band signed at Trident called Queen. He brought a bunch of these studio reels with him to play for my parents to give them an idea of some of the music that was currently under production there at the time and left the reels for them as a gift."

Jack Nelson and Chris Sandecki's father grew up together in Orange County, just south of Los Angeles - in the city of Tustin. Jack moved to London to work for Trident Audio Productions and was in the habit of carrying around sample tapes of what Trident could do, so that people could hear Trident's studio sound and also the groups they had under management.

Trident was probably the foremost studio of its time in England. It was a beehive of activity because of the engineers and the sound. Everybody from the Beatles and the Stones recorded there. Elton John made his first six or seven albums there. There were many others: David Bowie, Cat Stevens, Lindisfarne, and Carly Simon made her 'You're So Vain' album there.
[Source: "Follow the Music", the story of Elektra records as told by its founder, Jac Holzman]

Further information about Van der Graaf Generator's involvement with Trident can be found in The Book.