may 1, 1907 - American Lee de Forest invents the
triode valve. This device is used to
build electronic amplifiers.
Description:
Prior to this date, amplification of sound was mechanical; Bell’s telephone used a battery and microphone to send a voice along a wire, but there was no electronic amplification. Singers with dance bands of the time sang into large metal horns (megaphones) to make themselves heard. When recording, they sang into the large end of a similar horn, which directed the sound of their voice onto a small diaphragm at the other end. This transmitted mechanical vibrations directly to the cutting
needle.
Using valve amplifiers, microphones could be used to drive disc cutting heads to produce records, and of course singers could be fed to
loudspeakers, instead of singing into a 4 or 5 metre long megaphone.
Added to timeline:
Music Technology Timeline
A timeline of key events in the history of music technology....
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