i think there is an inherent conflict between the idea of "most EFFECTIVE demo track" and "most SALES" of a demo track. however; it seems like your aim is what demo track is the most popular. get's the most use. thinking about that makes my mind numb.
i'll come at this from another perspective. over the last 20 years, the track that i play to visitors that get's cited the most, as blowing their minds for being a live event right here right now is easily the 45rpm version of "Georgia" off the Ben Webster "Live at the Renaissance". played at Warp 11.
great live recording, great performance, and the media and system take full advantage. shows off all the attributes of the Big Rig. it has sparkle, tone, astonishing dynamics, and flow. the group just clicks. the live jazz club venue ambience lays itself out. and the supporting players are top notch. Ben's opening flourish is fully life like in the room; the power, liquidity, energy of the horn just perfect. at about 1 minute in, the drum whack can hit the low 200's on dart 468 'peak' RMS read out. THAT get's everyone's full attention. zero smear on that peak.
if you cannot play this at 'live' levels then don't bother as a demo track. it's a nice cut that sounds good. but at "live" levels (if you have the right tool for that) it transforms into a monster.
frigg'n effective for sure.
plenty of others to choose from. but pretty much this one captures everyone every time. and i rarely hear it at audio shows. and never, ever, like in my room.
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