So many excellent choices, that I will try to add something new.
For rock, LITTLE FEAT - Waiting For Columbus. This is a truly excellent recording and very nicely recorded. Its one of my go-to test albums
Here's one not mentioned: JOHN MCLAUGHLIN AND SHAKTI - their first album. It is a tour de force of musicianship, coupled with outrageously good recording technique. This is a masterpiece. eerie and enlighlening interactions with Zakir Hussain (RIP), L Shankar on violin and McLaughlin with his customized acoustic
PATRICIA BARBER - COMPANION: This is one of the regular test albums. A wonderfully recorded live gig, with great frequency range, soundstage, and on good equipment, the ability to put you right there in the club.
Last one - HOT TUNA - Live At The New Orleans House, Berkeley - fine recording in a club atmosphere,