Abstract: A recording method and system that provides optional and controllable song lyric acoustical promptings and music for Karaoke participants which is also capable of providing phonetic instruction for formative bilingual skill development. The acoustical prompts are in the form of short spoken phrases, acoustically provided just prior to the time at which the actual vocal should be sung. The method of acoustical prompting employs a listen--sing-along procedure effected via the interaction of the spoken instructor-promptings and the Karaoke participant. The acoustical system includes preparing a multi-track recording in proper time sequence to provide a precedent acoustical prompt. For example, the recording could have stereo music on two tracks, an original vocal on a third track in synchronism with the music, and on a fourth track rapidly spoken prompt messages preceding respective portions (vocal lines) of the original vocal.

Abstract: A recording method and system that provides optional and controllable song lyric acoustical promptings and music for Karaoke participants which is also capable of providing phonetic instruction for formative bilingual skill development. The acoustical prompts are in the form of short spoken phrases, acoustically provided just prior to the time at which the actual vocal should be sung. The method of acoustical prompting employs a listen--sing-along procedure effected via the interaction of the spoken instructor-promptings and the Karaoke participant. The acoustical system includes preparing a multi-track recording in proper time sequence to provide a precedent acoustical prompt. For example, the recording could have stereo music on two tracks, an original vocal on a third track in synchronism with the music, and on a fourth track rapidly spoken prompt messages preceding respective portions (vocal lines) of the original vocal.

Abstract: A circuit for protecting the ac generator and/or load of a diesel-engine generator set is provided. Included is a circuit for measuring indications of the current in each phase of the ac generator, and a switching circuit for protecting the ac generator if the current in any phase is greater than a predetermined current for a predetermined length of time (overcurrent), or if the current in any phase is less than a predetermined function of the currents in each of the phases for the predetermined length of time (imbalance). The circuit which protects the ac generator preferably short circuits the field winding of the ac generator and thereby turns off the ac generator, and/or closes a fuel valve to effectively turn off the engine should the current imbalance or overcurrent be sensed. In conjunction with the protection circuit, a switch interlock and/or circuit breaker arrangement for shock protection is provided.

Abstract: A circuit for protecting the ac generator and/or load of a diesel-engine generator set is provided. Included is a circuit for measuring indications of the current in each phase of the ac generator, and a switching circuit for protecting the ac generator if the current in any phase is greater than a predetermined current for a predetermined length of time, or if the current in any phase is less than a predetermined function of the currents in each of the phases for the predetermined length of time. For diesel-engine generator sets which generate three phase 460 V at up to thirty amperes continuously, the preferred predetermined overcurrent for any phase of the ac generator is thirty-five amperes, and the predetermined length of time (to permit inrush currents) is five seconds. Preferably the current in any phase should be less than fifty percent of the average of the current in the three phases.

Abstract: Method, system and apparatus correlate an audio message of an auxiliary sound source with an audio message from a sound track of motion picture film, video tape or other picture source with accompanying audio message track. This auxiliary source contains multiple language channels (also called "translation tracks" or "translation sound channels") running synchronously with each other. One such channel is a "prime language channel" including an audio message carrying the same information (possibly higher quality) in the same language as the message in the track accompanying the motion picture. This prime channel is derived from the same "master recording" (or high quality duplicate thereof) as the track accompanying the motion picture. Consequently the audio message conveyed by the prime channel (at high quality) is the same audio message conveyed by the motion picture track, but signals carrying those two messages may be quite different from each other: digital signal versus analog signal.

Abstract: A method and system for synchronizing a digital signal of an audio message at higher quality with another signal of the same audio message at lower quality. The invention synchronizes an auxiliary high quality audio digital sound signal source with the ordinary quality analog sound signal coming from a conventional analog sound track on motion picture film as the motion picture is being shown and maintains effective synchronization in spite of missing segments of the sound track due to film splices. The invention does not require synchronization tracks, markers, codes, time codes or other extrinsic data. The only requirement is that the higher qualtiy audio message recording, e.g. in a digital medium, be made from the same "master recording" (or a high quality duplicate thereof) as the sound track so that the auxiliary recording have the same informational content as the sound track.

Abstract: A stereophonic broadcasting system incorporating companding of the difference signal in which both the usual difference signal and a compressed version of the difference signal are transmitted to one or more remote receivers. At the receiver the usual, unchanged, difference signal is used as a reference signal for controlling the expansion of the compressed difference signal so as to cause the amplitude of the companded difference to equal the level of the usual difference signal. Thus, the expander is adaptive to any compression characteristic that might be employed at the transmitter. Further, the availability of the usual uncompressed difference signal at the receiver enables the adaptive decoding of dynamic parameters of the received signal, such as frequency response and attack and recovery times, so that all of the parameters of the original signal can be restored automatically.

Abstract: The disclosure applies to an audio recording apparatus which receives audio signals, generally from a tape recorder, and forms grooves in a spiral pattern on a recording disk. The apparatus typically includes a turntable for rotating the recording disk, a cutter for cutting grooves in the disk, and a cutter transducer for modulating the instantaneous position of the cutter as a function of the audio signals. An electromechanical subsystem is responsive to control signals for directing the unmodulated position of the cutter; i.e., its unmodulated radial position with respect to the center of the disk and its unmodulated vertical position or depth. In accordance with the invention, there is provided a system for automatically generating the control signals which control operation of the electromechanical subsystem. When no modification of the unmodulated radial position is called for, none is made, thereby eliminating wasteful pitch modifications.

Abstract: An apparatus and method for decoding four individual audio signals to the extent they are contained in first and second composite signals. The first composite signal contains the first individual audio signal in dominant proportion and two other individual audio signals in subdominant proportions. The second composite signal contains the second individual audio signals in dominant proportion and two other individual audio signals in subdominant proportions. In accordance with the invention there is provided a means for measuring the degree of directional predominance of each of the four individual audio signals. Means responsive to the composite signals are employed to form four partially decoded signals, each of the partially decoded signals including a different one of the individual audio signals in dominant proportion and two other individual audio signals in subdominant proportion. The four partially decoded signals are respectively applied to four output terminals.