DCS Digital to Digital Converter ユーザーズマニュアル
dCS 974 User Manual
Manual for Software Version 1.0x
dCS Ltd
May 2001
Manual part no: DOC1241121A1
Page 107
Document No: OS-MA-A0124-112.1A1
Contact
dCS
on + 44 1799 531 999
email to: more@dcsltd.co.uk
(inside the UK replace + 44 with 0)
web site: www.dcsltd.co.uk
Noise Shaper, Noise Shaper with Dither, and Dither Only Comparison
dCS 972 SW v1.54
-160
-140
-120
-100
-80
-60
0
2
4
6
8
10
12
14
16
18
20
22
Frequency (kHz)
A
m
pl
itude,
R
eal
D
at
a
(dB
)
16 bit truncation, Noise Shaped Triangular dither
16 bit truncation, Top Hat dither
16 bit truncation, 10th order noise shaping, Noise Shaped Triangular dither
16 bit truncation, 10th order noise shaping, no dither
44.1 kS/s sampling, 1024 point FFTs, H6 window, -90 dB 1.44 kHz input
Figure 48 – Noise Shaping and Dither Spectra
Spectra of -90dB 24 bit sinewave truncated to 16 bits with dither options
dCS 972 SW v1.54
-91.00 dB source signal
-89.70 dB 16 bit truncated
-160
-140
-120
-100
-80
-60
0
2
4
6
8
10
12
14
16
18
20
22
Frequency (kHz)
A
m
pl
itu
de (
dB
)
24 bit source data
16 bit truncation, no
dither
dither
44.1 kS/s sampling, 1.44 kHz input, 1024
point FFTs, H6 Window
Figure 49 – Truncation Only Spectra