Volume compensated stereophonic phonograph

Claim 1

IN A STEREOPHONIC AMPLIFIER FOR PLAYING PROGRAM SOURCES OF DIFFERENT INHERENT LOUDNESS AND HAVING TWO AMPLIFYING SOUND CHANNELS, THE COMBINATION COMPRISING TWO VOLUME CONTROL NETWORKS HAVING CONNECTIONS WITH SAID RESPECTIVE SOUND CHANNELS TO VARY CONTROLLABLY THE VOLUME OF ELECTRONIC SOUND SIGNALS WHICH ARE TRANSMITTED THROUGH SAID RESPECTIVE CHANNELS; EACH OF SAID VOLUME CONTROL NETWORKS INCLUDING CIRCUITRY THAT IS RESPONSIVE TO A VARIABLE CONTROL VOLTAGE APPLIED THERETO TO EFFECT A CONTROLLED MODIFICATION OF THE LOUDNESS OF THE SOUND SIGNALS PASSING THROUGH THE CORRESPONDING CHANNEL, WHICH MODIFICATION IS SUBSTANTIALLY UNIFORM IN DEGREE FOR ALL SOUND SIGNALS PASSING THROUGH THE ASSOCIATED CHANNEL AND WHICH IS A FUNCTION OF THE CONTROL VOLTAGE APPLIED TO THE VOLUME CONTROL NETWORK; A VOLTAGE INTEGRATING NETWORK HAVING AN INPUT SIDE AND AN OUTPUT SIDE AND INCLUDING CIRCUITRY WHICH RESPONDS TO THE APPLICATION OF A VARIABLE VOLTAGE TO THE INPUT SIDE OF THE INTEGRATING NETWORK TO PRODUCE AN OUTPUT VOLTAGE WHICH IS A FUNCTION OF THE VOLTAGE, AVERAGED OVER A PERIOD OF TIME THAT IS SUFFICIENTLY LONG TO ENCOMPASS THE PLAYING OF A NUMBER OF MUSICAL NOTES OF NORMAL DURATION, THAT IS APPLIED TO THE INPUT SIDE OF THE INTEGRATING NETWORK; MEANS INCLUDING TWO RECTIFIERS CONNECTING THE INPUT SIDE OF SAID VOLTAGE INTEGRATING NETWORK TO SAID RESPECTIVE SOUND CHANNELS AHEAD OF THE CONNECTIONS WITH THE SOUND CHANNELS OF SAID RESPECTIVE CONTROL NETWORKS TO MAINTAIN THE INDEPENDENCE OF SAID CHANNELS AND AT THE SAME TIME APPLY TO THE INPUT SIDE OF SAID INTEGRATING NETWORK A VOLTAGE WHICH IS A FUNCTION OF THE LOUDNESS OF THE LOUDER OF THE TWO SOUND SIGNALS IN SAID CHANNELS, AND MEANS INCLUDING TWO RECTIFIERS CONNECTING THE OUTPUT SIDE OF SAID INTEGRATING NETWORK IN CONTROLLING RELATION TO SAID RESPECTIVE CONTROL NETWORKS.