DCS 900E User Manual page 13

dCS 900E / 902E User Manual
dCS Ltd
Word Length
Noise Shaping
The AES/EBU format accommodates data up to 24 bits. If a shorter word is
needed and the extra bits are just ignored, the result is typical "digital" sound
due to the abrupt chopping off of the low level signal information.
To avoid this, the dCS 900 / 902 allows proper truncation of the data and uses
Noise Shaping to maintain low level performance. See the section on
Length Reduction"
Word Length
without realising it.
Pressing the
sequence:
The Word Length is briefly shown on the main display, and if a setting other than
the maximum is set, the word length LED (above the button) lights.
Noise Shaping is a technique which improves the noise performance of the ADC
in the audio band by moving the quantisation noise energy (introduced by
reducing the word length) from the middle of the band, where the ear is most
sensitive, to the top end or ultrasonic region, where the ear is less sensitive or
insensitive. See the section
background.
Pressing the
Shaping characteristics. The characteristic is shown briefly on the main display.
Auto
Off
1st
3rd
9th
The noise shaping LED (above the button) lights when the setting is other
than Auto.
Overload Level
The
panel) it sets the level at which overloads are detected by the unit. With the
other menu buttons
Overload detection is normally set to full scale. The detection level may be
reduced in 0.1dB steps down to -3dB0 by pressing the
repeatedly or holding it down. The set level is shown on the display for a few
seconds. The overload level LED (above the button) lights when the setting is
other than full scale (0.0dB0).
For Menu operation as the
Menu"
Manual part no: DOC0029021E1
Contact on + 44 1799 531 999
dCS
(inside the UK replace + 44 with 0)
All manuals and user guides at all-guides.com
-
-
on page 50 for some background on this. If you do use
truncation, make sure that
Word Length button repeatedly cycles the word length through the
24, 23, 22, 21, 20, 19, 18, 17, 16, 24,
"Word Length Reduction"
Noise Shaping button repeatedly cycles the unit through 5 noise
Unit sets noise shaping automatically, depending
on word length:
24 bits – no noise shaping
20 to 23 bits – 1
16 to 19 bits – 3
No noise shaping
st
1 order noise shaping
rd
3 order noise shaping
th
9 order noise shaping
Menu Step
Overload Level button is dual function – on its own
(white type on the front panel) it is the menu
Step
on page 18.
Page 13
Manual for Software Versions 1.3x to 1.5x
Noise Shaping
on page 50 for more
st
order noise shaping
rd
order noise shaping
(blue
Overload Level
button, see the section "The Software – The
Document No: OS-MA-D0002-902.1E1
email to: more@dcsltd.co.uk
web site: www.dcsltd.co.uk
th
12 June 2000
"Word
is not set to OFF
etc.
type on the front
Step button.
button