Signedon right earphone: Permoflux Corp. / Chicago, U.S.A.
on plug: General Radio / Co.
Inscribedon both earpieces: Patent pending
top of headset: 107-4
on the wire: P-23
on the plug: General Radio / Co. / type 274-MB
on left earpiece: Type / 49456 / P/O / H-3/ARR-3
on right earpiece: CQF / PDR-8
Historical AttributesBetween 1940 and 1945, Harvard physicists and psychologists worked side-by-side to bring man and machine into a harmonious union. Communication equipment studied and engineered by the Electro-Acoustic Laboratory was sent to the Psycho-Acoustic Laboratory for speech articulation tests with human subjects in high-noise or low-pressure environments. Leo Beranek's and Stanley Stevens's teams developed improved microphones and earphones, and the armed forces rushed these into production.
As one can see from this example, the "patent pending" found on the headset establishes it as something new and innovative. The doughnut-style earphone socket came to be known as Harvard Socket. Stevens used this improved headset to study sound transmission in a noisy environment.
ProvenancePsycho-Acoustic Laboratory , Harvard University
Published ReferencesBrandon Shackleford, When Noise Signals Change: The Electro-Acoustic and Psycho-Acoustic Laboratories from 1940 to 1945 (Senior thesis, Harvard University, 1997). CHSI Lib.4875.