| 摘要 |
<p>PURPOSE:To increase dynamic range characteristics and to simplify and make small the circuit constitution, by saving the electric power supply for phase shift circuit and mixing circuit and the like. CONSTITUTION:Unidirectional microphone units M21, M22 are located serially with a specified interval toward a sound source S. An output terminal of the M21 is commonly connected to each one end of a resistor R11 and a capacitor C11 constituting a phase shift circuit PS21. Another end of the resistor R11 and the capacitor C11 is connected to both ends of a winding N1 at the primary side of a transformer T11 constituting a mixing circuit MIX21. The output terminal of the M22 is connected to one end of a winding N2 at the primary of the T11, and another end of the winding N2 is grounded commonly to the neutral point of the N1. An equalizer circuit EQ21 is connected to a secondary winding N3 of the T11. In this circuit constitution, the T11 plays a role of a part of the PS21 and the MIX21 substantially.</p> |
