I've noticed that recordings of singers from the 1920s-1940s are generally noticeably higher in pitch than singers from the 1950s-1960s. I know that something to do with the mechanics of making the recordings caused earlier ones to be higher, but is that all that there is to this difference? Before I heard about the mechanical issue, I thought this was in part social - higher voices being more fashionable earlier in the century. Am I totally off, musicologists, or is this just about how music was recorded?
I assume on the tech level you’re thinking of acoustical vs electrical recording right? Or are you thinking of something else? Recording speeds? Professional CD transfers will have had sound techs knowledgeable in historic recordings balancing them out and going through old catalogs and such for the proper speeds so people don’t sound like Alvin and the Chipmunks on accident, if you’re listening to professional transfers you can trust your personal observations on tone pretty well.
Electrical recording started up after 1925, so making observations about what voices were favored with the crude early sound technology only works for 1890s-1920s. And you’ve actually got it a bit flopped if you’re thinking of acoustical recording tech! It favored medium-tone voices mostly, and struggled to capture the full range of frequencies in the extremes of sound, so it disadvantaged sopranos and basses both, and favored tenors and baritones, and to some level contraltos. Enrico Caruso’s wild success with selling records is sometimes linked with his voice being in the perfect range for the technology’s limitations, so a tenor sounds pretty much like a tenor, and most of his frequencies were captured, while a soprano sounds pretty tinny compared to real life, as many of her (or his!) frequencies were not captured. Maybe you can make a pitch that early recording tech helped out the tenor’s rise, but that’d be a complicated argument, considering he was on the rise many decades before sound recording. And loooord knows there’s a whole bunch of squeaky-sounding soprano recordings from this period, but contraltos are pretty rare, so the tech argument doesn’t work so hot on women. (I only know this stuff from my study of the Alessandro Moreschi recordings, which are subject to these problems.)
I think you can make an argument that people’s taste in tones has changed over time to be more open to low voices though. I’ve got an article analysing the favoring of high male voices from art music to gospel to pop you might find interesting, let’s see if this link gets caught in the spam filter, you can read quite a lot of the Cleary article in Google Books before it cuts you off.