Sony STR-DA7100ES Technical Background page 7

carefully at the pulses, you'll see that where the audio waveform is positive, the
pulses are mostly 1. Where the audio waveform is negative, the pulses are
mostly 0. In this way, a 1-bit pulse stream can represent the audio signal. As
with a DSD signal, a Low Pass Filter (LPF) is all you need to recover the original
audio signal.
In the diagram above, (A) represents the output power pulse stream.
This combines two components, the original audio signal (B) and a
noise component (C). The audio signal (B) looks smooth and
continuous because the frequencies are low. The noise component (C)
looks abrupt and spiky because the frequencies are high. The Low
Pass Filter (LPF) effectively separates out the audio signal, for
extremely accurate music reproduction.
Inside the S-Master Pro process
While Sony's S-Master Pro amplifier is simple in principle, the fidelity of
the output signal depends on getting each pulse exactly right. That is, the
leading and trailing edges of each pulse must have the right timing—and the
height of each pulse must be carefully controlled. This is comparable to the
requirements for Super Audio CD playback. So to accomplish these goals, Sony
used technologies developed for our legendary SCD-1 Super Audio CD player.
Sony's CXD9773Q S-Master Pro LSI incorporates several stages of
crucial signal processing.
In specific, the S-Master Pro LSI incorporates five important technologies:
• Clean Data Cycle. "Jitter" or time-base errors can degrade the accuracy of
digital signals. That's why the first stage of the S-Master Pro process is
Sony's Clean Data Cycle. This regenerates the digital signal with time-axis
accuracy equivalent to the original A/D converter at the recording studio. In
ES Receivers v1.0 Page 7