Glai,
Piano's excellent. It's percussive, which gives you a well defined leading edge, but it also has a complex harmonic trail. Choose something dynamic (Beethoven) rather than a soft legato (Debussy). Listen for the relative timing between hammer strike, string fundamental, string harmonics and body reverb. A piano-forte or harpsichord are even better than a modern piano because their sounds are crisper, clearer and tighter.
On Saturday we heard Emanuel Ax from the 5th row of Hartford's fairly intimate Belden Theater. He played Beethoven's 4th concerto and also a Mozart double concerto, with Mrs. Ax on the other piano. She's a technically strong and rhythmically solid pianist. He's... almost indescribably beyond that. His technique and sense of the music's internal rhythms are so solid you don't even hear him being solid. You tend to notice his gloriously complex tone and long, singing lines. Within an infallible rhythm Ax somehow caresses each single note: iron fist within a velvet glove. The audience was properly ravished.
... and of course they both played with perfect SRA. ;-)
***
What's wrong with the HFN record's anti-bias tracks is self-evident if you think about what they actually do. Those tracks bear no relation to the amplitudes and frequency mix of real music. They're not designed to emulate real music. They're designed to present progressively severe tracking challenges that will CAUSE your cartridge to mis-track. This ennables one to adjust A/S to balance lateral groove pressures for the absolute worst-case scenario.
If every record you play is that extreme, then by all means use the HFN tracks. If, OTOH, you play real music then adjusting A/S for the worst case scenario will result in too much A/S for all other records. Adjusting your car's suspension and tire pressures for 180-200mph laps on the track may not give you optimal performance or ride when tootling around town at 35.
It's more accurate and realistic to adjust using real records and it helps train your ears. If some amount of A/S makes your soundstage more organized to the right or, like Peterayer, it helps with body and presence, then by all means use that amount. That's the method I've always recommended based on real music, not intentionally unrealistic test tracks.
@Peter, your A/S description gave me some idea what to expect from your system when we visit. Now I'll have to apply some anti-bias of my own! ;-)
