Apparatus for combining phonograph signal with auxiliary audio signal

Claim 1

Audio signal apparatus for combining an auxiliary audio signal with each of a plurality of audio signals emanating from a primary audio signal source such as a phonograph or the like, comprising a primary signal source for producing a plurality of first audio signals, an auxiliary device for producing independently of said primary source a second audio signal from a source having a relatively high impedance compared to that of said primary signal source, means for combining said second signal with each of said first signals to produce a plurality of composite audio signals each comprising components of said first and second signals, and an amplifier for amplifying said composite signals and for applying the amplified signals to one or more speakers, said combining means including means for attenuating the low frequency portion of said second signal prior to combining said first signals with said second signal, thereby to prevent distortion of the amplified composite signals, and said combining means further including means for selectively adjusting the amplitude of said first and second signals, respectively, whereby one of the signal components of each of said composite signals may be amplified greater than the other.

Claim 5

A device for superimposing at least one audio signal from a first source onto each of a plurality of audio signals produced by a phonograph, which is independent of said first source, prior to amplification of the composite audio signals by a phonograph amplifier, comprising a housing having therein a plurality of signal inputs, a pair of resistors in said housing, means for connecting an audio signal from said first source through at least one of said signal inputs commonly to one end of each of said resistors, means for connecting a pair of audio signals from said phonograph through two others of said inputs and respectively to the opposite ends of said resistors, adjustable means for adjustably connecting said two resistors intermediate the ends thereof to two separate inputs of a dual amplifier, said first source having a relatively high impedance compared to that of said phonograph, and said means for connecting said first signal source to said resistors including means for suppressing the low frequency portion of said signal from said first source, thereby to prevent signal distortion which would otherwise occur upon amplification of the composite signal by said dual amplifier.

Claim 6

A device for superimposing at least one audio signal from a first source onto each of a plurality of audio signals produced by a phonograph, which is independent of said first source, prior to amplification of the composite audio signals by a phonograph amplifier, comprising a housing having therein a plurality of signal inputs, a pair of resistors in said housing, means for connecting an audio signal from said first source through at least one of said signal inputs commonly to one end of each of said resistors, means for connecting a pair of audio signals from said phonograph through two others of said inputs and respectively to the opposite ends of said resistors, adjustable means for adjustably connecting said two resistors intermediate the ends thereof to two separate inputs of a dual amplifier, said first source having a relatively high impedance compared to that of said phonograph, and said means for connecting said first signal source to said resistors including means for suppressing the low frequency portion of said signal from said first source, thereby to prevent signal distortion which would otherwise occur upon amplification of the composite signal by said dual amplifier.