What Instrument would you listen to?

Ok, this is not the real world, but if you HAD to audition a rig (for purchase) listening to only one acoustic instrument; what instrument would be your lynchpin?
Piano, for me.
No single instrument covers all the parameters that go into good sound, so using just one as a reference is a bad strategy unless that is all you will ever listen to. Human voice ( male and female), acoustic piano, drums, bass, violin and electronic synthesizer would cover it fairly well together.
Does anyone hear actually buy an entire rig preassembled? With a single instrument, you can get a feel for timbral accuracy, so its a good place to start, but clearly you have to move on to music that uses multiple instruments and voices to complete the evaluation.

But to answer your question. Piano first, followed in order by cello, violin, french horn, then soprano and tenor voices.
I have heard speakers that do all of these well but fail on piano. That is a deal breaker. On the other hand, I have never heard a speaker that gets piano right and fails on the rest. So the lynchpin is piano.
Piano is the instrument capable alone of getting one the furthest however.
Percussion instruments. Dynamics, harmonic structure, transient response, decay, the whole nine yards.
Human voice. Spoken, sung (individually and in choir) and male and female variants.
I agree in this scenerio the piano is a good choice. But take it a step further, which recording?
Nothing is more important than timbre. That's the thing no system gets accurate enough to be considered LIVE.
I feel that guitar comes closer, better, to a variety of instruments, voice included than any other that I am familiar with. It can have a percussive quality to it, a voice quality to it, it can carry a rhythmic quality or foundation of a piece. It is an instrument that speaks in a variety of ways to to me. For some reason colors come to my mind when I listen to music and for me the guitar creates more colors than any other accoustic instrument that I know of.
Theo, Beethoven Waldstein sonata, Andreas Schiff on ECM always goes with me on auditions.
Brownsfan, thank you, two selections I am not familiar with but am going to amazon to obtain. Thanks again.
Solo piano for sure, an instrument I'm very familar with, live and recorded. But as you said, its not the only thing I listen to when auditioning stuff.
Theo, Beethoven's Waldstein sonata is my favorite of the 32 sonatas he wrote. Also, it is a great piece for equipment audition. Very dynamic and engaging. You can listen to it 1000 times and not tire of it, which can be helpful when you are auditioning equipment.
I like to use good recordings of recent vintage for auditions. The Schiff account on ECM of this sonata is a pretty decent recording. Not sure if he used a Steinway or Bosendorfer grand for the Walstein. The Paul Lewis recording of this sonata is also probably very good, but I haven't heard it yet.
Brownsfan, if you don't already have it try to find the 1981 recording on the Astree label of Paul Badura-Skoda performing the "Waldstein" and two other Beethoven Sonatas on an early 1800's fortepiano. I have it on LP as Astree AS73. Not sure if it was ever released on CD. An absolute treasure, musically and sonically!

Best regards,
-- Al
Brownsfan, I did find it on Amazon on the ECM lable and am ordering it once I get my order completed, I realize that it was ONE selection you suggested not two as I said. I did see a number of other listings but am sticking with your suggestion, I have been realy wanting to get a good piano recoding for evaluation as well as enjoyment.
Again thank you for your help.
I find, when the cymbals sound right, the highs fall into place, but that is it for these ears. A Bosendorpher piano (sp?) is the piano I want to hear. Those extra notes would certainly help clinch the deal.
My own. :)

I actually do often audition equipment with horn music, sometimes with recordings of my orchestra.

But to give a more serious answer to your question, the human voice would be the one to use, and not just sung, but also spoken. The horn is not a bad second choice, though, as it has one of the more pure timbres, acoustically speaking, among the orchestral instruments.

Some folks recommend piano because it is a difficult timbre to duplicate. If you want to try another very complex tone acoustically, than the oboe is a good choice. But if the more pure timbres are not resolved very well, then certainly the more complex ones won't be, so I would first use instruments with less complex timbres.
Almarg, they are out of print. Looks like they are going used for ~ $80-200.00. It also looks like some of his recordings are being reissued. I will keep an eye open for reissues.
I remember the sales guys in the shops being proud of certain speakers capable of reproducing piano exceptionally well. It's not an attribute one would have to discover on their own. So I think a well informed individual would by necessity choose piano firstly.
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Piano is almost a consensus which is difficult to find in any audiophile discussion, but drums is of great interest too me as well simply because they are so hard to get right and can tell you so much about your system's performance.
brushes on a snare and cymbals are a major major for me. For me, analog does it best. Hey,I'm hi-jacking my own thread.
Learsfool is right on the money. And his opening remark is particularly
useful; even if he made it partly in jest.

I would add that the piano is best from the standpoint of using an
instrument with the most extended frequency range. That is obviously an
important consideration when auditioning gear. Also, if the gear is a
turntable, nothing like checking speed stability with piano decays. Now, as
far as timbre goes, I have always had trouble with the notion that the sound
of any one instrument is more difficult to reproduce than another. And that
takes me back to Learsfool's opening remark.

ALL instruments (and voice) are difficult to reproduce accurately; and I
would suggest that they are all equally useful in assessing the ability of
gear to reproduce timbre. It all depends on which instrument (or voice) we
are each most familiar with or have the most affinity for (maybe the same
thing). True, some instruments have a more complex tone than others. But,
does that not also mean that the ones with the less complex tones will be
more difficult to differentiate? IOW, as Learsfool states, the horn (his
instrument) has one of the most pure tone structures. I am sure he would
agree that, as a result, the differences in tone between each member of his
horn section are that more difficult to differentiate than, say, the oboists'
tones. But the differences are certainly there; and to Learsfool, very
obvious; because he is intimately familiar with the sound of the horn. So, it
follows, that gear that can reproduce the subtle differences between
various horn sounds will, as he points out, easily reproduce obvious

BTW, while I agree that the reproduction of timbre is key for realism, I think
that most gear has gotten good enough that an even more important,
elusive, and unfortunately overlooked aspect of music playback is dynamic
nuance. As far as I am concerned, that is the area that separates the men
from the boys (in gear).
Oh, and I also agree 100% with Frogman's final comment about dynamic nuances being what separates the men from the boys in gear. To be absolutely clear, this especially means on the SOFT end of the spectrum.