Technical blog topics
It is important to understand that TDA1541(A) wasn’t one simple point in DAC chips history, but the end and crown of its own era, in which DAC chips did not perform any kind of processing.
In the Model S USB, TDA1541A operates in simultaneous data mode, and this is why Model S USB is practically free of data related jitter artifacts.
Model S USB is the only DAC with TDA1541A operating in simultaneous data mode.
Tthe Model S USB uses TDA1541A and it is up to 192 kHz compatible device. It means that it does not downsample, neither inside the DAC nor at PC side, but it just converts any 44.1/48/88.2/96/176.4/192 kHz file directly, at its native frequency.
As opposed to the S/PDIF, USB is a bidirectional protocol that makes possible to make a peripheral device (here the D /A converter) act as a master device, and PC as a slave that delivers the data only when and as requested by the DAC. This way, the overall clock performance at the DAC is not related to and limited by the quality of PLL used, or by PC. It is solely determined by the quality of free running oscillator, placed locally in the DAC. Such a solution became lately known as an “asynchronous USB”.
