| 摘要 |
<p>PURPOSE:To achieve the reduction in the weight and cost of a loud speaker device by providing a speaker unit connected to a transformerless amplifier. CONSTITUTION:The primary side and secondary side of a transformer 1 are insulated and the audio signal 7 and an amplifier 3 connecting to a commercial power source via transformerless power source is insulated. A demodulator 12 receives the radio waves, light, acoustic waves, etc. transmitted by a modulator 11, demodulates the audio signal and supplies the audio signal to the amplifier 3. With respect to the insulation of the output of the amplifier 3, making the connection of a voice coil 4 and the output of the amplifier 3 in an ordinary way is satisfactory because the voice coil 5 is generally insulated from the outer frame 4 of the speaker.</p> |
