Prior Threads on Recordings for Judging Audio System Quality
It has been many years since I've listed recordings I've found particularly useful for making judgments about audio equipment. Prior threads in Tom's Corner listing such recordings and bearing on the issues involved include:
Component Auditions at Your Dealer: What Recordings to Use and How to Use Them
An Example of a Component Audition at a Dealer: Applying My Method and Afterthoughts
"You Are There" Absolute Sound: Can We Get There From Here? Part One
How Recordings Are Made vs. Concert Hall Realism at Home: Piano Recordings
"You Are There" Absolute Sound: Do We Even Want to Go There?
When You Only Want One: A Single Orchestral Test Disc
While many of these threads are about ten years old now, the examples and methods are just as relevant now as they were then. Granted, hearing equipment set up well at a dealer is a good deal harder to find these days and audio shows are on a pandemic hiatus. But anywhere you can actually audition equipment before buying it, or even after purchase, the recordings and methods I've mentioned in these prior discussions are, I think, still just as relevant.
I would make one clarification: The Rutter Requiem disc on Reference Recordings is the single most useful tool for using classical music to judge equipment that I know. If your interests in classical music go beyond mere orchestral works (the subject of the "Single Orchestral Test Disc" thread) then the Rutter Requiem on Reference Recordings has not only outstandingly fine orchestral sound, but also state-of-the-art recording of pipe organ and massed choral voices. Just make sure that the CD player, streaming service, or file you use has properly decoded the HDCD encoding of the original. These days this should not be a problem as long as Roon, Qobuz, or Tidal services are used for the audition or you bring your own decoded file to the party. If you put the original HDCD-encoded CD in a disc player these days, however, the chances are high that the player will not decode HDCD and the sound will not be anywhere nearly as realistic as it should be. Most current model players do NOT decode HDCD from optical discs. That functionality was dropped from many DAC chipsets several years ago as new HDCD releases became rarer, ordinary Redbook recording techniques got better, and DSD, MQA, and Hi-Res PCM came on the scene.
Changing Criteria: "The Absolute Sound"vs. Personal "Good Sound"
Of course, a lot has changed in the last decade with respect to audiophiles' belief in the relevance of the "absolute sound" of unamplified acoustical instruments as heard from a favorable seat in a good concert hall to how music should sound at home. Even ten years ago this was already a minority viewpoint carried over from the founders of The Absolute Sound and Stereophile. Today, most all reviewers seem to be striving for "good sound." however they define that term--that is, if they even bother to define it.
Because of the loss of "the absolute sound" as a paradigm for judging home audio reproduction, there is also increasing disagreement on whether the goal of home audio reproduction should be "they are here" immediacy of the group in your listening room or "you are there" transporting of the listener to the venue where the recording was made (if there even was such a venue--with multitrack studio assembled recordings there may never have been any real venue where the musicians were physically assembled to play together to be heard by an audience).
However, my purpose here is not to judge the state of audiophile standards of sound reproduction. My audiophile roots were primarily in classical music reproduction--thus the type of recording lists I've made and the issues I've discussed in the threads I've written discussing those recordings.
But even for me, I'm not ashamed to admit that in the past decade my musical tastes have broadened and my appreciation for other recording techniques has increased. My tastes are much more eclectic these days. I still don't appreciate a lot of current mainstream recordings. For example, most of the new releases on Tidal are examples of current musical genres which I just don't care to listen to. But my appreciation for pop, classic rock, folk, jazz, electronic, and country music has greatly increased over the past decade. And with that more eclectic musical taste I've also come to better appreciate the virtues of hearing closely miked or electronically captured music sound as though it is live in your listening room rather than more distant, as when you would hear it in a club or concert hall. Thus, for some music, I can now better appreciate the preference of many listeners for the "they are here" type of reproduction as the goal, rather than "you are there."
There are also new tools available these days which are incredibly helpful in the quests for great sounding recordings and recordings of music you love. Streaming services generally and Roon in particular are fabulous tools which make both quests more enjoyable and efficient.