The late great Oscar Peterson was gifted a Bosendorfer late in life and he used that low register a lot. If you can find recordings by Telarc you might hear it. Also the series "Exclusively For My Friends" originally recorded on BASF in the Black Forest has him playing on a Bosendorfer that I believe has those low notes. There is also a great recording by Ahmad Jamal entitled "Ballades" on Harcourt of Paris that captures the full scale of the piano magnificently.
Why not the piano as a reference for bass
I see a lot of commentary/reviews on a systems bass response that all seem to hinge on the 41 hz double bass and such range. At 27.5 the A0 note on a piano seems a better point to judge. Lots of piano in normal music vs say an organ note. I know when I feel that deep chord played it is one of things I enjoy about listening the most! Was listening to Wish you were here live and the piano was sublime.
So is it more of how much musical energy is perceived in the 40 hz range or what that makes this more of a reproduction benchmark?
I welcome your input!
New Joe Bonamassa out BTW!