Best song for immediate impact when presenting or testing?


I, as most of you, have my regular tunes that I play or listen to when trying out a new system or playing music for friends. My current starter is 'Feels like Rain' by Aaron Neville. It engages me immediately because I love it so, but it is also very well recorded and has a bass voice doing backup which in the right system has a real visceral impact.

I was at an Audio shop recently, listening to my standards, and wanted to show the sales consultant a piece that he might not have heard. I played 'Golden Rust' off the Miles Gurtu album. After about 30 seconds, he pulled out his device and added the song to his favorites. I asked why did he add so quickly, and he said that the opening electronica had a three dimensional stereophonic quality that made a remarkable impression right off the bat. I paraphrase lightly; that was his comment.

What pieces do you play of any genre that have an immediate impact, especially for people listening to a good system for the first time?
128x128cmjones
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I just heard the ATCSCm40 speakers,  'wow' and super 'wow'.  The track they played was Sans Saens - Danse Macabre.  I know this track well but hearing it through these speakers bought out the full majesty of this music.  The speakers have this skill of portraying the actual tone/timbre of the musical instrument.  This piece has various instruments playing this lovely sort of demonic/cemetery tune, hearing the violins was exquisite pleasure. Also I could hear each instrument seperately in the orchestra or enjoy the full orchestra at once. The whole experience was like a thrilling ride on the big dipper in a fair ground!
There are so many great tunes which were well recorded... When I was selling audio gear in the early 80's I used Joni Mitchell's Court and Spark for vocals.. if I wanted to show off dynamics or impact of a kick drum I used Bruce Cockburn's Wondering where the lions are.. Heard that once on a pair of Infinity Rs 4.5's driven by a Mark Levinson ML 3. Search that one out. Again so many great ones to use.