There has been extensive discussion on the subject of sound board crown,
and also on the benefits of the Baldwin "Acu-just" hitch pin.

The full text archive search of the pianotech list is located at this
URL.  Type in 'sound board crown', down bearing, hitch pins, etc., and
see what the techs' opinions are.

    http://www.webcom.com/wind/ptsearch.html

Jon Page
Harwich Port, Cape Cod, Mass. (jpage@capecod.net)