Thanks, W.B.lbl, I am learning (albeit very slowly ... ) ;-)
I doubt I'll ever recognize these fonts as surely as you do, but at least you sharing your font expertise gives me and others a chance to pick up on the differences.
On {Images #2448153 & 2448154}: 12 point Linotype Spartan Heavy for cat. # and song titles, 10 point Spartan Heavy for artist, 7 point Spartan Heavy for matrix #, and 6 point Trade Gothic Bold Extra Condensed for everything else. Typesetting by Co-Service Printing of Newark which handled the Rockaway plant from late 1955 until early 1959.
Bert-Co's type on Hollywood-pressed {Images #2447736 & 2447737} was a bit different than what I mentioned to 'xiphophilos': 12 point Spartan Heavy for cat. # and song titles, 10 point Spartan Black for artist, 6 point Metroblack No. 2 for matrix # - and 6 point Gothic Condensed No. 4B for everything else except the "HIS MASTER'S VOICE."
The Indianapolis 78 (and, for that matter, 45) used various Varityper fonts here, the only evidence of Monotype typesetting is the Alternate Gothic No. 1 to spell out ' "NEW ORTHOPHONIC" HIGH FIDELITY'. 7, 10 and 12 point Sans Serif Bold, 7 point Sans Serif Medium, (possibly) Statistical Gothic No. 387 (for music publishing) and 3 point Copperplate Gothic Cap & Small Cap (for matrix # and running times), comprise what else was used here.
This entry combines all three variants of RCA Victor's late "New Orthophonic" Color Nipper label, Indianapolis, Hollywood, and Rockaway.
The following info is adapted from info by fellow moderator W.B.:
Hollywood pressings {Images #2447736 & 2447737} are the only ones that list the trademark "His Master's Voice" below Nipper. They used Bert-Co Press typesetting: 10 point Linotype Trade Gothic Condensed (cat. # and song titles), 6 point Gothic Condensed No. 4B ("Collectors" and recording dates), and 6 point Metromedium No. 2 (everything else).
W.B., could you please add the types used by Rockaway?