The objective of this work is to minimize the deleterious effects of loudspeaker cable impedance when driving dynamic loudspeakers, accomplished primarily with a mathematical feedback analysis on the prominent role of the cables themselves within the audio baseband feedback loop. Presented are the measured system waveforms, along with computed root loci and transfer functions of a proof-of-principle remote-sensing (4-wire) 80 watt audio power amplifier. A single baseband feedback loop compares the incoming audio information (voltage) to the resultant voltage across the loudspeaker electrical terminals and minimizes the difference. Measured waveforms demonstrate notably superior replication of incoming information at the loudspeaker terminals over the audio band. The system is empirically robust for a wide range of dynamic loudspeaker and cable systems without any need for electronic adjustment. For example, with 35 meter 15/22 gauge cabling, a bandwidth of 72kHz, dynamic range of 110dB, phase linearity of <0.5°, and low impedance drive levels of <0.2O at the loudspeaker terminals are readily achieved simultaneously.
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