CD or turntable, whether digital music player that is read from the storage medium, processing the output high-fidelity audio data stream. The output data stream timing precision and accuracy of data on the logo of the player's high-fidelity performance advantages and disadvantages.

　　CD turntable in order to read the data required the introduction of servo system and laser reading systems, which are part of the circuit and institutions will also be possible to introduce data errors and timing errors. CD turntable in high-grade fever and therefore to reduce the error, using such as: increased weight to increase the dial wheel inertia, with suspension system to circumvent the Non-constant friction, using the optimized high-level servo motor circuit to improve the operational stability, order special sound to the whole frame method to reduce vibration and so on. But in any case the introduction of error, and the number players do not need these two parts, not this part of the error.

　　HIFI performance impact of two important indicators: clock accuracy, clock jitter (Jitter). General CD turntable clock accuracy are more than 100ppm, while the number of players can be raised to the following 1ppm. As for the clock jitter, the digital player can do the following 1ps, the general CD turntable in more than 100ps. Only a few expensive CD turntable can these two indicators increased to very high.

　　While those MP3/MP4 player, these two indicators is more mess, and seriously affect the decoding algorithm for data output timing, and because the system bus is shared, it can not guarantee a strict timing, timing error is normal for a few clock cycles things. This is why some people can listen to the APE, FLAC sound reasons for the differences, in fact solved the problem of data is no different, but the difference came to the release. So MP3/MP4 not to mention HIFI. This is also the reason the computer sound card is difficult to HIFI.