| 摘要 |
<p>PURPOSE:To reduce distortion of speaker cords surely with a simple constitution, by including the transmission line due to speaker cords to constitute a feedback loop. CONSTITUTION:Terminal OUT'(+) to be connected to the feedback input of negative feedback circuit 3 consisting of impedances R1 and R2 is provided in the output of amplifying circuit 2 and is connected to + terminal P1 of speaker 4 by speaker cords L1 and L1'. Terminal OUT'(-) is provided at the ground terminal in negative feedback circuit 3 and is connected to - terminal P2 of speaker 4 by speaker cords L2 and L2'. Terminals OUT(+) and OUT(-) and speaker cords L1 and L2 are used as forcing termiansls and cords by which the driving signal to speaker 4 is transmitted, and terminals OUT'(+) and OUT'(-) and speaker cords L1' and L2' are used as sensing terminals and cords by which the actual driving signal at terminals P1 and P2 of speaker 4 is detected and sent to negative feedback circuit 3. Consequently, speaker cords are ignored apparently by negative feedback.</p> |
