Musical accompaniment device and musical accompaniment system using ethernet audio transmission function

Provided are a musical accompaniment system and a musical accompaniment device to which a plurality of audio output devices are connected. The musical accompaniment device comprises: a sound source input unit to which an analog/digital audio signal is inputted from a microphone converting a voice signal or instrumental signal to an electrical signal, or from a sound source device providing an accompaniment sound source; an A/D converter for receiving the inputted analog audio signal and converting the inputted analog audio signal to a digital audio signal; a controller for converting the digital audio signal to an Ethernet signal and transmitting the Ethernet signal to an external audio output device; and an Ethernet communication interface for supporting an Ethernet communication so as to transfer the Ethernet signal to the external audio output device, wherein the controller comprises a clock synchronization unit for performing clock synchronization such that the Ethernet signal transmitted to the outside is received at a music relaying device, which is Ethernet-connected, at the same time, by periodically exchanging timing signals with the music relaying device, thereby minimizing an audio output delay in a plurality of speakers at different locations.