What is the One Test Track That Tells You Almost Everything About A System?

I use several different tracks, depending on the age and musical tastes of a person I'm demoing my system to, especially my Audio Concepts ACI,  Sapphire III LE speakers. If they are familiar with Fleetwood Mac I'll put on Go Your Own Way  for their instrument and vocal presentation and any others they know, as these Audio Concepts speakers are very clear and accurate with both, even at higher volumes. Nearly any songs by the Eagles work nicely too.

For more modern country-rock style music I'll select some Midland, like Drinkin' Problem, Mr. Lonely, Playboys and Longneck Way To Go. Also in this style or genre is Brothers Osborne with It Ain't My Fault, All Night, Skeletons and Might As Well Be Me. Some Toby Keith, George Strait, Kenny Chesney and Old Dominion work well too.

If anyone is familiar with Latin music, I'll put on some Diego Verdaguer Mala, Tonta and others from Organico album, because of the style of music with so many different vocals and instruments used just come alive.  I'll also select some Marc Anthony, Enrique Iglesias, Pitbull for mixing up Latin style music. 

If someone likes Reggae, then of course it's Bob Marley, Shaggy, Inner Circle, or some Big Mountain songs to demo.  If it's different types of rock or hard then it's some U2, INXS, ACDC, Ozzy, Nirvana, Aerosmith,  Eric Clapton, etc.

We are regular people, so we have our stereo with my home theater in our open concept living room that is open to our kitchen and dining room, so no special room treatment or positioning away from the wall, just 5.2 surround positioning as best as as we could. We use an older Yamaha AVR with 2 separate older Marantz 5 channel amplifiers to bi-amping our Audio Concepts Sapphire III LE's, so nothing hi-end or very expensive, but nice. Two subwoofers, not matched brand for now, but nicely integrated.

I just enjoy sharing my love of music along with my passion for the smaller, independent speaker manufacturer of Audio Concepts,  Inc ACI speakers, as I grew up with one of their builders, as he was my dad's best friend growing up. 

If you ever have the chance to listen to them, please do so, as they are a great hidden secret in hi-fi speakers. Very hard to find since they retired as a company in 2007 or so, but once in a while they will show up on Ebay, Audiogon, Reverb or US Audio Mart, and if you are very lucky maybe on Facebook Marketplace. 

I hope this will open your mind towards smaller, independently built speakers, as their are some amazing ones out there at different price points for nearly everyone. If you are a handy person who can do some cabinet building, there are some great DIY kits or plans out there to match or even exceed some of the more manufactured high volume speakers. 

Enjoy the music for what ever system you may have.

Some very good suggestions here. I’ve heard most of them. A really good, dynamic old classic rock tune is one by Elton John called Mad Man across the water. The original 8:52 version, not the short version, its not very good. Give it 75-80 db, amazing!

I found a Bella Sonus (Enamoured) cd at half price books many years ago. It’s been one of my favorite go tos ever since. I’m happy to see it mentioned in this thread.

I’m surprised no one has mentioned Liberty by Anette Askvik

I understand why so many folks choose Jazz - it is so easy...  

To me Jazz can have excellent SQ, but it will always be insufficient for evaluating audio systems.

Why?  Jazz may be the least complicated group-base music being recorded today.  Perhaps, this is why nearly every equipment vendor at every audio show uses jazz for demos.  Although most jazz recordings are often uncompressed and natural-sounding, jazz is completely insufficient for honest system demos.

Go from 4 or 5 instruments to 80+ instruments, and you have a recording that has a real opportunity to both challenge and show-off your system.

For me, Gustav Holst's The Planets works very well.  Full orchestra, NINE octaves of sound, full dynamic range - typically 30 to 100 dB (a 70 decibel range), 90 to 100 instruments/performers.   Now that will challenge your system...

When I ask vendors to play it, I usually see anguish in their faces... 

Caveat - it must be an excellent recording.

Good luck ;-)

https://open.qobuz.com/playlist/3511772