Just to add to David Dewey's note on A=435 Hz vs. A=440 pitch standard
[170405 MMDigest].  The A440 pitch standard was adopted by the Musical
Industries Chamber of Commerce in 1925, the American Standards
Association in 1936 (now known as ANSI) and the American Federation
of Musicians (AFofM).

Further, J. C. Deagan noted that the A435 pitch standard is set at 59
degrees Fahrenheit (essentially for outdoor use) and the A440 standard
is the same pitch, brought indoors, where the temperature may range
from 68 to 72 degrees F. and is close enough.

Grant Chapman
West Point, New York

 [ MMDigest articles on this subject are indexed at
 [ http://www.mmdigest.com/archives/KWIC/P/pitch.html 
 [ -- Robbie