WM8756

Advance Information

AI Rev 1.3 October 2001

7

DIGITAL FILTER CHARACTERISTICS

PARAMETER

SYMBOL

TEST CONDITIONS

MIN

TYP

MAX

UNIT

Passband

±0.05 dB

0.444fs

dB

Stopband

-3dB

0.487fs

Passband Ripple

±0.05

dB

Stopband Attenuation

f > 0.555fs

-60

dB

Table 4 Digital Filter Characteristics – PCM operation

SACD FILTER CHARACTERISTICS

With 64fs DSD data where fs = 44.1ks/s.

RESPONSE

FILTER RESPONSE WITHOUT POST-

FILTER

FILTER RESPONSE WITH 3

BUTTERWORTH POST-FILTER (-3dB AT 55KHZ)

Pass band peak ripple

0.017dB

0.017dB

Attenuation at 20kHz

-0.012dB

-0.021dB

Attenuation at 50kHz

-2.3dB

-3.9dB

Attenuation at 100kHz

-15.5dB

-31dB

Table 5 Overall frequency response in SACD mode.

TERMINOLOGY

1.

Signal-to-noise ratio (dB) - SNR is a measure of the difference in level between the full scale output and the output with no

signal applied. (No Auto-zero or Automute function is employed in achieving these results).

2.

Dynamic range (dB) - DNR is a measure of the difference between the highest and lowest portions of a signal. Normally a

THD+N measurement at 60dB below full scale. The measured signal is then corrected by adding the 60dB to it. (e.g.

THD+N @ -60dB= -32dB, DR= 92dB).

3.

THD+N (dB) - THD+N is a ratio, of the rms values, of (Noise + Distortion)/Signal.

4.

Stop band attenuation (dB) - Is the degree to which the frequency spectrum is attenuated (outside audio band).

5.

Channel Separation (dB) - Also known as Cross-Talk. This is a measure of the amount one channel is isolated from the

other. Normally measured by sending a full scale signal down one channel and measuring the other.

6.

Pass-Band Ripple - Any variation of the frequency response in the pass-band region.