Dolby Deterioration


It’s my belief that recordings made in the 50s and early 60s, before the advent of Dolby, sounded more open and detailed than records made later. You can here the difference even in digital transfers of the earlier discs.  I’ve maintained this for many years.  I wonder if anyone else has noticed this phenomenon.  
Adding to the further deterioration, was the trend away from tubes to solid state equipment.
its a pleasure to hear pre solid state, and especially pre Dolby presentations.
128x128rvpiano
I found the change in recorded sound between Rubber Soul and Revolver jarring; I much preferred the sound on Rubber Soul, and still do. It wasn't until years later that I read Abbey Road had switched from tubed recording equipment to solid state between those two albums.
I agree, though there are some exceptions. Who needs transistors, anyway, if you have good tubes and know how to make them work ?
I am not familiar with Dolby SR.

Speaking of Dolby.....I’ve always been mystified why Tea For The Tillerman is considered to have such good sound quality. I have had an original UK pressing of it since its’ release, and always found the drums to sound very muted---with no snap and stick-on-the head sound, and the cymbals almost absent. The acoustic guitar strings also lack sparkle and that "scratchiness" of the pick sliding across them.

Michael Fremer discussed the difference between his original UK copy and the reissue on Mobile Fidelity, and panned the reissue, saying the highs has been boosted. Can you guess where this is heading? Turns out whomever mastered the original didn’t know it had been recorded with Dolby, so didn’t put the signal through the second half of the Dolby process, the part that restores the frequencies depressed during recording! The original is missing it's high frequencies, it's no wonder I don't hear the cymbals!

That was not the case when Mobile Fidelity remastered the album. Their version was done using the correct Dolby processing, and their LP is what the recording actually sounds like. To his credit, it was Fremer himself who brought this to everyones’ attention. He may be full of himself, but he’s a big enough man to admit a mistake.

Dolby SR or Spectral Recording was Dolby’s piece de resistance for analogue tape/film recording. It is still sold by Dolby as part of their Dolby Analog suite

Review
https://rapmag.com/a/39-90/mar90/152-test-drive-dolby-sr-model-363-sr-a?showall=1
Schematic from manual
https://i.vgy.me/wWKZUz.png