If you could just pick one instrument that you think sounds best on your speakers

What would it be? I love my OHM 5000s. The instrument of my choice would be the synthesizer. I'm now listening to EL&P's songs Tank and Tarkus on CD. Ive just played them 3 times because it gives me good frisson. (Other thread). In the opening of Sade "Smooth Operator" the synthesizer sounds like its notes are moving all around in the room. It's the same with Tears for Fears "The Working Hour". 
So if you could just pick one instrument that your speaker plays the best at. What would it be? I'm sure this would be a tough question for some members because there are many great speakers that do very good at all music. It might also be one instrument you like hearing best anyway. So what would be your choice? 
I also have Thiel 2.7 speakers, and I agree with prof o the oboe; however I also have a ss2.2 subwoofer, and I really like the sound of a Bosendorfer piano. 
Apogee Duetta II's sound great on everything except rock, but really excel on piano and solo voices
Saxophone.  On my Merlin VSM Black Magic speakers, it sounds perfectly natural and real.  When I put in a good recording of Getz Gilberto, for example (reel to reel or Analogue Productions 45RPM vinyl reissue), you can hear the spit flowing through the sax during the solo in Girl from Ipanema. 

I sort of did, but okay. Quad ESL (originals), Magneplanar Tympani T-IVa, Eminent Technology LFT-8b and LFT-4, ESS Transtatic I, Optimus Pro LX5, NHT Super Zero, Stax Lambda Pro Earspeakers, GR Research/Rythmik OB/Dipole Subs, Rythmik F15HP DIY Subs (in 4cu.ft. sand-filled enclosures of my own design).

I can listen to just about anything on one or more of the above, but my main interest these days is in vocals and acoustic instruments. Still, I want to hear the new Music Reference ESL speakers with direct-drive OTL amps. Plans are underway ;-) .

Acoustic guitar  - EgglestonWorks Fontaine Signatures