SD-10 Clarification

[Roger Jolly]

 It also had a spring
>mechanism on each key that would eliminate the need to weight keys with
>lead.
>
Hi Charles,
                  Jon Ralinovsky, had just put a new set of Abel hammers on
the piano, it sure sounded sweet in that size of theatre.
We never pulled the action, the observation was from above. 
Kind of strange to look at so many holes in the plate and bridges, I
presume to mount transducers to measure results.
Do you know if Harold had any conclusions with regards to harmonic content
of the duplex?
The reason for the question, he advocated de tuning, yet this seemed to be
tuned close on the octave, and certainly sounded cleaner.
Or was it a question of too much precision required in mfg?
Roger

Roger Jolly
Saskatoon, Canada.
306-665-0213
Fax 652-0505