This isn't in any way to denigrate what's already been presented - I had forgotten about this book, of which I have a copy. The background to H. Burrell Hadden was that he joined the BBC in 1946, moved through the technical ranks and eventually became an instructor in 1959. He was closely involved with most of the BBC's original stereo experiments.
[quote author="PRR"]
Is there more to the article? It mentions Plates 8.2 to 8.4, which I don't see. The value of the stereo channel fader is not given. A complete hook-up (not the block diagram) would be handy.
Also: the sum-difference mixing is novel. Is there a previous chapter to explain this to people who never worked this way? [/quote]
No, there isn't any more to the article. The plates that relate to this are from 8.1 to 8.6, and unfortunately there isn't a complete hookup - what is given is, to say the least, rather incomplete. As far as the sum and difference system is concerned, there is a little more information, but it consists of no more than a description of the classic Blumlein MS recording technique, really. The purpose as far as this mixer is concerned is to provide width controls on the stereo channels. There is a stack of information about this available online, one way or another.
I think the number on the bottom of page "116" should be 470KΩ not 470Ω.
I think that it should be too - and I have amended my version of the pdf accordingly. This isn't the smallest pdf in the world (7+ MB), but it does contain the plates, and the scans, whilst not absolutely perfect, are of a higher resolution. I don't want to leave it where it is for too long, but if anybody fancies transferring it to the archive, that's absolutely fine by me.
The pdf is presently
here.