Amazing what you find!
I was just trawling the "net" today looking to see if there was any mention of the Court Spectrum Analyser and I came across this webpage. http://www.themillrecordingstudio.com/acoustics.html
Nice mention of how things were in the heyday of recording studios and it was the the Court Spectrum analyser that was being used I think.
Stephen would have appreciated the name check, it was a good studio.