| 摘要 |
<p>The present invention relates to a direct box and a direct box system, more specifically to a direct box and a direct box system capable of monitoring high quality audio without a restriction of place by outputting sound of a playing instrument to an in-ear earphone directly or transmitting the sound through a bluetooth communication by a player or a singer. The direct box includes an unbalance signal input terminal, connected through an output terminal and a line of an instrument, for receiving an unbalanced signal composed of a (+) polarity signal and a ground signal from the instrument; a converter, connected with an input terminal of the unbalanced signal, for conversing the unbalanced signal to a balanced signal composed of the same phase and the same amplitude of the (+) polarity signal and the ground signal and a (-) polarity as a negative phase and outputting; a balance signal output terminal, connected with the converter, for outputting the balance signal to the outside; a pre-amp, connected with the unbalanced signal input terminal, for outputting an amplifying signal by amplifying the unbalanced signal; and an earphone output terminal, connected with the pre-amp, for outputting the amplifying signal to an external in-ear earphone.</p> |
