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如今VCD已进入千家万户,但VCD机的音质难以令人满意。尤其在播放CD唱片时,效果往往不如普通的CD唱机。分析原因,系多数VCD机所用DAC芯片和运放电路档次较低,电阻、电容也多为普及型,加之CD信号也要经过解压板上的解压芯片处理,理论上说是作直通处理,实现上会有一定的损耗和失真。针对这种情况,许多生产厂家纷纷推出较为高档的DAC摩机板,将VCD机改装为CD/VCD双线路机。改装原理是直接从DSP芯片处取出BCK、DATA、LRCK三路信号,然后经DAC摩机板进行数模转换、低频放大、输出音频信号。
VCD has now entered millions of households, but the quality of VCD machines unsatisfactory. Especially playing CDs, the effect is often not as good as a regular CD player. Analysis of the reasons, the majority of VCD machines used DAC chip and op amp circuit lower grade, resistance, capacitance and more for the popular type, coupled with the CD signal decompression board also go through the decompression chip processing, in theory, for through processing, to achieve There will be some loss and distortion. In view of this situation, many manufacturers have introduced a more upscale DAC Motorcycle board, the VCD machine converted to CD / VCD dual circuit machine. Modified principle is taken directly from the DSP chip BCK, DATA, LRCK three-way signal, and then by the DAC Motor Board digital-analog conversion, low-frequency amplification, the output audio signal.