Yamaha AW2816 Owner's Manual page 230

Dithering digital signals
When a song recorded with 24 bit quantization is
recorded on an external 16 bit recorder via the DIGI-
TAL STEREO OUT jack or a digital I/O card, the lower
8 bits are automatically discarded. As desired, you
can apply dithering to the signal that is output at this
time.
In this section we will explain how dithering can be
applied when the AW2816's DIGITAL STEREO OUT
jack is connected to the digital input jack of a DAT
recorder, and you mix down a 24 bit to the 16 bit DAT
recorder.
DIGITAL
STEREO
OUT jack
AW2816
Tip!
When a digital audio signal is transferred from a
higher-resolution system to a lower-resolution system,
the quantization noise caused when bits are rounded-
off may be objectionable. In such cases, a small
amount of random noise can be added to the signal to
make the quantization noise less obtrusive. This pro-
cess is called "dithering."
1
Press the [SETUP] key
key.
The SET UP screen/Dither Out page will appear.
In this page you can turn dithering on/off and
specify the word length (number of bits) of the
output signal for the DIGITAL STEREO OUT jack
and the output channels of the digital I/O card.
DAT
00.00.00.00
DIGITAL
STEREO
DAT recorder
IN jack
[F3] (Dither Out)
Operation section
2
Move the cursor to the ON/OFF button in
the DIGITAL ST OUT area, and press the
[ENTER] key to switch the button ON.
Use the ON/OFF buttons in the Dither Out page
to enable/disable dithering for each output jack/
output channel.
Tip!
• Turning dithering on has no effect if you are trans-
ferring from a lower-resolution system to a higher-
resolution system (e.g., 16 bit
ring between systems of equal resolution (e.g., 16
bit 16 bit).
• For a digital I/O card, dithering is switched on/off in
odd-numbered even-numbered pairs of output
channels (1/2, 3/4 ...)
3
In the WORD LENGTH (BIT) area of the
DIGITAL ST OUT row, move the cursor to
the "16" button and press the [ENTER] key.
In the WORD LENGTH (BIT) area you can select
the word length (number of bits) of the digital sig-
nal that will be output. Normally you will move
the cursor to the button for the word length that
corresponds to the receiving device, and press
the [ENTER] key.
• Changing the word length will have no effect on a
channel for which dithering is turned off.
• Be careful that dithering is not applied twice or
more to the same source. If this occurs, the effect of
dithering will be lost and the S/N ratio will be
degraded.
4
Start recording on your DAT recorder, and
then play back the AW2816 song.
The lower 8 bits will be automatically discarded,
and the dithered 16 bit audio will be recorded on
the DAT recorder.
Settings in the Dither Out page are common to all
songs. If you do not need dithering, be sure to turn
OFF all buttons in the ON/OFF area.
Tip!
Dithering can be applied in the same way when
recording tracks or the stereo track within the
AW2816. For details refer to page 260
24 bit), or transfer-
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