Totally agree with you regarding Dolby B. I find the post 65 discs that were made
from those tapes totally devoid of high frequency air and so avoided them.
The system I enjoyed more was DBX which was miles better but never caught on somehow but in the right recording could sound breath-taking. In the sixties and seventies I was very friendly with a BBC engineer who worked in Glasgow and recorded most of the radio 3 broadcasts using 15 IPS Studers. He was made to use Dolby B for a while but later was allowed to use DBX for a few years till it became redundant . I remember one concert he taped which was in City Hall in Glasgow. It was supposed to be Ida Haendel playing the Sibelius Violin Concerto. Unfortunately Haendel was ill and she had to be replaced and it was a startlingly young Nigel Kennedy playing the Tchaikovsky Concerto and it was wonderful and this was before the career killing move to not play dead composers any more. I digress but The next week I was in Glasgow again and dropped in on Jimmy and he was working on a recording he had take the previous week and it was on 15 IPS with DBX. It was fabulous with no trace of tape hiss and superb dynamics which totally blew away Dolby D.