Perceptual Effects of Dynamic Range Compression in Popular Music Recordings - January 2014
Accurate Calculation of Radiation and Diffraction from Loudspeaker Enclosures at Low Frequency - June 2013
New Measurement Techniques for Portable Listening Devices: Technical Report - October 2013
Phillip Reis - From the First Telephone to the First Microphone
On October 26, 1861, Phillip Reis presented a lecture to the members of the 'Physikalischer Verien' in Frankfurt, Germany. The subject was entitled 'The transmission of tones via galvanic current over wide distances'. His telephone consisted of a thin membrane which produced, with the frequency of sound, a change of the current by just switching a contact. This was easily transmitted to the receiver at around a 200 m distance. The corpus of a violin was shook by a small electromagnetic device which was known from telegraphy. The violin irradiated the sound in such a way that a melody could be heard. Even some words and short sentences were transmitted. For his work and his many improvements he received the title 'Meister des Freien Deutschen Hochstifts'. This 'Hochstift' and it's scientific work was the offspring of the later founded Frankfurt University. The work of Phillip Reis was published in technical periodicals at that time. Some years later, his telephone was produced by a small company in Frankfurt which sold the sender and the receiver all over the world. The small village of Freidrichdorf, located in the Taunus hills near Frankfurt, was, at that time, not interested in having wire connections from village to village. In the 1860's many small German states existed before the unification in 1871. Ten to fifteen years later the need for communication lines using the new telephone of Graham Bell was extreme. Now Phillip Reis was remembered as the first inventor. For him however, it was too late. He died in 1874. The idea of a so called contact microphone was overtaken by the electro-magnetic system of Bell, changing the amplitude of transmitted current. The next step was the invention of Edison's carbon microphone. The paper will describe the work of Phillip Reis at the beginning of a new century of telecommunication technology.
Click to purchase paper or login as an AES member. If your company or school subscribes to the E-Library then switch to the institutional version. If you are not an AES member and would like to subscribe to the E-Library then Join the AES!
This paper costs $20 for non-members, $5 for AES members and is free for E-Library subscribers.