Pythagoras and Musical Scales (circa 550 B.C.)
http://en.wikipedia.org/wiki/Musical_scale

Hildegard von Bingen - St. Hildegard (1098-1179)
http://www.hildegard.org/
http://www.newadvent.org/cathen/07351a.htm

History of the Piano
http://en.wikipedia.org/wiki/Pianoforte

Bartolomeo Cristofori (1656-1731)
Invented the first pianoforte around 1700

During the last three years of his life, J.S. Bach used a pianoforte made by Gottfried Silbermann.

Mozart used slightly more sophisticated pianos built in Vienna by Nannette Stein and Anton Walter.

John Broadwood & Sons built the first modern pianos beginning around the time of the American Revolution.
In 1785 Thomas Jefferson visited the Broadwood Factory.
In 1817 a Broadwood Piano was given to (the almost deaf) Beethoven.

Giuseppe Verdi (1813-1901)

Thomas Alva Edison (1847-1931)
http://en.wikipedia.org/wiki/Thomas_Edison

Amy Beach (1867-1944)
http://www.pbs.org/wnet/ihas/composer/beach.html
Charles Ives (1874-1954)

Menlo Park, New Jersey - "Birthplace of Recorded Sound" (6 December 1877)
http://www.edisonnj.org/menlopark/

Billboard Magazine - Launched in Cincinnati, Ohio (1 November 1894)
http://www.billboard.com/bb/bb110/1894.jsp

William Grant Still (1895-1978)
http://www.shs.starkville.k12.ms.us/mswm/MSWritersAndMusicians/musicians/WGStill.html

George Gershwin (1898-1937)

Walt Disney (1901-1966)
http://disney.go.com/vault/read/walt/index.html

Louis Armstrong (1901-1971)
http://www.rockhall.com/hof/inductee.asp?id=59

Les Paul (1915-)
http://www.rockhall.com/hof/inductee.asp?id=164

John Lennon (1940-1980)
http://www.rockhall.com/hof/inductee.asp?id=143

Paul Simon (1941-)
http://www.rockhall.com/hof/inductee.asp?id=188

Joseph Schwantner (1943-)

James Taylor (1948-)
http://www.rockhall.com/hof/inductee.asp?id=198

Jelly Roll Morton (1890-1941)
http://www.rockhall.com/hof/inductee.asp?id=157

Gennett Records - Richmond, Indiana - "Cradle of Recorded Jazz" (1916)
http://www.waynet.org/nonprofit/gennett.htm

First Broadcasting of Radio Programs (1920)

First Public Showing of a Motion Picture with Sound (1926)

First Broadcasting of Television (1936)

John Williams (1932-)
http://us.imdb.com/name/nm0002354/

American Federation of Musicians - Local 1 Started in Cincinnati, Ohio (1881)
http://musicians1.org/

Powel Crosley - Cincinnati, Ohio - (1886-1961)
Made Radio Listening Affordable (1922)
National Association of Broadcasters formed (1923)
Made Radio Broadcasting Powerful (circa 1934)

Stock Market Crash (1929)

President Franklin Delano Roosevelt initiates Fireside Chats via Radio Broadcast (1933)