Captured Angel was a very late SQ title. Likely that's the reason that you got a Quad in a stereo jacket with the letter. Likely, they ran out of Quad sleeves and weren't inclined to print more, since Quad was on its' way out. Nor were they inclined to dump the extra SQ LP's pressed, hence, the letter.
Very interesting Linda..! :upthumb
With the greatest respect (after all, you know so much more about all this than I do.. I wasn't even born!
) I'm not entirely convinced that is the whole story.. the Thrust SQ that was found by ClarkNovak inside a stereo sleeve with the same letter as my Fogelberg was from 1974 and this Fogelberg was from 1975..
and my Rock On SQ in stereo sleeve, bought new like that according to the bloke I bought it off (but without the letter) must have also been purchased when Quad was in full swing around '73/'74, no?
Also, how late is the Fogelberg Quad?
Afaik there were Columbia (and assoc label) SQ LPs of non-Classical repertoire for some time after these titles?
At least those SQ LPs I've picked up like..
Burton Cummings (1976),
EW&F - Spirit (1976),
Harold Melvin - Wake Up Everybody (1976),
Tower Of Power - Ain't Nothin' Stoppin' Us Now (1977),
Aerosmith - Rocks (1976),
Andy Williams - Andy (1976),
Jeff Beck - Wired (1976),
BT Express - Energy To Burn (1976),
Herbie Hancock - Secrets (1976),
Isley Brothers - Harvest For The World (1976),
Isley Brothers - Go For Your Guns (1977),
O'Jays - Message In The Music (1976),
Maynard Ferguson - Conquistador (1977),
The Manhattans - It Feels So Good (1977),
The Miracles - Love Crazy (1977),
Phoebe Snow - Second Childhood (1976),
Ted Nugent - Free For All (1976),
Santana - Festival (1977),
Johnnie Taylor - Ear'gasm (1976),
Johnnie Taylor - Rated Extraordinaire (1977),
Wild Cherry - Electrified Funk (1977),
Return To Forever - Musicmagic (1977)
..are all in proper Quad sleeves.
One theory I'd heard, it was partly because retailers used to bundle all Quad LPs together in the same bin in their stores and that combined with consumer apathy led to the Quads languishing unsold.. this little trick may have been a brainwave to get them into the racks with all the other stereo discs and to get people to try out Quad when they got a Quad record.. by stealth! Curious..