The KLH 9's sounded natural and current. I was amazed to be believe these speakers designed in 1957 and made public in 1960 pre-date me. I will turn 53 this February and to be honest I would have thought that today's speakers would have to sound exponentially better, and that is just not the case.
Hearing and physically touching them was for a way of connecting to a piece of history: Hi-FI Americana. It made me want to connect a turntable and play any number of Mercury Living Presence RCA Living Stereo recordings. So many of those recording featured American composers and symphonies of the time.
As I mentioned in my post, if you are at all interested, David Janszen has a limited number of KLH 9s to which minor modifications are being made for today's residential use. His email is in the original post, and you can contact him directly.