Great Recordings, Sonically Speaking - and Why.

I think many of us would accept that artists such as Pink Floyd, Steely Dan, and Dire Straits have consistently put out music that was at least originally recorded to a high technical standard. [I'm not too sure what the loudness wars may have done to subsequent reissues, but even so, the tone and timbre thankfully tends to remain intact.]

However there must be plenty of lesser known recordings out there that could be said to be of a high sonic standard.

One such recording that I like to put on in the background whilst I'm doing other things is a piano recording that features wonderfully lush timbre and some delightful tunes.

This one is The Disney Piano Collection by Hirohashi Makiko and to me it makes a lot of other piano recordings sound a little washed out.
I have enjoyed Hugh Masakeka Hope.  Great live recording.  Really puts your system through its paces
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As Wolfie says, look for early Audio Fidelity pressings.  One features Louis Armstrong and one of his last bands as well as Thelma Middleton, and the sound is spectacular.  Audio Fidelity also packaged this disk with one by the amateurish Dukes of Dixieland and, amazingly, actual got Louis to record yet another record with them (what a mismatch).  This was only sold as a three record set as a private label offering by EJKorvette, the early discount chain. I own that set, and while I don't know for sure I suspect it is worth a fair amount of change.  The individual Dukes-only recording and the Armstrong recordings were also sold as singles.

BTW, that discount chain had sound rooms in each of its stores in the late fifties/early sixties.  Filled with Japanese receivers.
The Halloween Shuffle from the Henry & Reinhardt EP The Halloween Ball. Great bass and pipe organ, cool sound effects. A very fun way to show off your system.
I agree with Coltrane 2. Jazz at the Pawnshop is the best live recording I have ever heard. I close my eyes and I'm sitting center at a table 12 feet from the stage, 30 feet from the bar in the back round ( hearing mild talk and clanging glasses). The music is melodic, traditional jazz with a very mellow flair. The acoustics are superb. I have over 3,000 LPs and this one is in the top 2 or 3 for sound quality and presence. You do not have to be a jazz purist to love this it if you can find it. And thanks to Coltrane 1 for bringing it to everyone's attention.