... from an audiophile perspective, how does one listen to mono recordings? For example, does ’imaging/soundstage depth’ matter and is it accomplished through a well-mic’d mono recording? Obviously tonal balance, impact, resolution are all qualities that should shine through...
Basically, you listen to mono recordings as you would stereo recordings--for the music. Most of the the traits you mention--soundstage depth, tonal balance, impact, and resolution--are strengths in mono recordings. If, however, you derive much of your listening pleasure from 3D imaging of each voice and instrument, you won’t find that on mono recordings.
But mono recordings have strengths that stereo recordings don’t. Generally they have a richer tonal balance, stunningly real-sounding midrange, and perhaps the biggest surprise, a deep soundstage, particularly on sacred vocals recorded in a cathedral or instrumentals in an auditorium.
Would appreciate recommendations of well recorded MONO LP’s -- recently bought a Julie London LP in mono it sounded surprisingly nice/natural... not so hot as many later stereo pop recordings... my musical preference would be for vocals in pop, jazz and soul/r & b realms..If you think about it, many recordings from the mono era (1949 to mid 1960-is) feature vocals with instrumental accompaniment. This was the heyday of Sinatra, Bennett, Crosby, Ella Fitzgerald, Sarah Vaughan, and Nat King Cole. I have a mix of mono recordings--originals from the ’50s and ’60s rescued from thrift shops, and high quality mono reissues such as the wonderful EMI/Parlophone Beatles mono reissues of Sept. 2014, plus several Beach Boys releases by Capitol, as well as a 45 rpm 3 LP set by Acoustic Sounds of Nat King Cole. Nothing puts Nat in my living room like that one.
If you are into hunting down vintage mono releases, you are in for a treat if you get a mono cartridge to go with it. Apparently most of the surface noise of an LP occurs in the vertical axis. I have several genuine mono albums from the ’50s and ’60s (some all the way out to 1969) that are unlistenably noisy with a stereo cartridge which are dead quiet with a mono cartridge.
After a year of listening to my 2014 Beatles mono reissues, I decided to get a mono cartridge. I chose the Audio Technica AT-MONO3/LP, available from US authorized dealer LPGear.com for $189.99. It’s a high output moving coil cartridge with a conical stylus, which seems--to me--most appropriate for original mono recordings from the ’50s and ’60s. I opted to get mine from a Japanese storefront on eBay for $112 and change, but currently they’re around $117. Search Amazon for Audio Technica AT-MONO3/LP and you'll get several returns in that price range.