I don't know if any of these items have ever been pointed out in this thread as I'm not allowed to search in the thread.
My favourite tracks to test my 2-channel system is with fifties recordings that have not been contaminated with all kinds of digital gimmicks (maybe a few in re-mastering)
Looking at that period, the Capitol, RCA en CBS recordings always stand out. With Capitol at the asbolute top.
To mention a few:
My man - Peggy Lee. To see if your system is able to let you hear the difference between a kick drum and a string bass that are very close and on the same channel.
There is no sweet man that's worth the salt of my tears - Peggy Lee. That voice (in all of her songs) is simple magic and very well recorded for the time thanks to Olson and his design of RCA mics.
Isle of Capri - Frank Sinatra. The roar of those drums gives me goose bumps every time I play it. And that "just behind the beat" singing of Frankie is unmatched
Just walking in the rain - (gentleman) Jim Reeves. That very low RCA bass and the rock solid recording of that magic voice.
In the "old" recordings on the other side of the ocean Decca is a name worth mentioning and Parlophone (EMI) as second.
You don't know - Billy Fury
I'm looking out the window - Cliff Richard (original by Peggy Lee has more feel to it, but is too old for me to be a fine recording)
OK, for some more modern material
Bubbles - Yosi Horikawa. Nice playing with all kinds of ball sounds. Can you point them all out?
Draw your swords - Agnus and Julia Stone (by the end of the song it gets too messy the rest if fine)
Walking on the moon - Yuri Honing
Maze - Olaf Stuut
Die Tänzerin - Ulla Meinecke (sings in German, so not everybody's cup of coffee. But very nice electronic sound and beautiful decay in here singing)
Nardis - Patricia Barber. Drum solo, drum solo and drum solo. Please search for the unmastered version
Misa Criola: Kyrie - Mercedes Sosa. The space around that chorus, the lead voice and the delicate instruments
Sure there are plenty more good tracks, but I keep coming back to most of these over and over again.
Enjoy your music.