Справочник Пользователя для Tascam RC-898
Section 7.2 - Unit-related functions
7-5
2) Use the
LEFT
and
RIGHT
keys to select a unit,
and the
UP
and
DOWN
keys to change the
setting between
Digital
and
Analog
.
See p15 and pp25-26 of the DA-88 manual for fur-
ther information regarding this facility.
ther information regarding this facility.
7.2.8 Varispeed (pitch control)
The DTRS design allows for
±
6.0% speed control,
in 0.1% increments.
1) From menu group 0, move the cursor to
Vari
Spd
, and press
SELECT
:
2) Use the
UP
key to change
Fix
to
Vari
, or
the
DOWN
key to change
Vari
to
Fix
.
The
VARI
indicator [10] will light if
Vari
is
selected, even if the setting is
0.0%
, and will go
out if
Fix
is selected, even if the setting is not
zero.
3) Move the cursor to the right (numeric) field,
and use the
UP
and
DOWN
keys to set the
value.
7.2.9 Input selection
DTRS units can accept either digital or analog
inputs. The choice of which inputs are to be used
for each machine is made in the following way:
inputs. The choice of which inputs are to be used
for each machine is made in the following way:
1) From menu group 9, move the cursor to
InputSel
and press
SELECT
:
2) Use the UP and DOWN keys to select between
the digital and analog input sources for each
unit.
unit.
In the screen above, units 1 through 4 are accept-
ing analog signals, while 5 and 6 are using TDIF -
1 digital inputs.
ing analog signals, while 5 and 6 are using TDIF -
1 digital inputs.
7.2.10 Word length
The DA-38 and DA-98 units are able to
accept digital data at their digital I/O connectors at
either 16-bit, 20-bit or 24-bit word lengths. These
settings are made in the following way:
either 16-bit, 20-bit or 24-bit word lengths. These
settings are made in the following way:
1) From menu group 2, move the cursor to
Word
Len
, and press
SELECT
:
2) Use the
UP
and
DOWN
keys to select between
16
,
20
and
24
bit word length of incoming
data, which will be converted to 16 bits for
recording purposes.
recording purposes.
If you select a value higher than
16
, you may
want to experiment with the Dither settings (see
7.2.11, “Dither”, below), as this may help with dis-
tortion, though a little may be lost from the signal-
to-noise ratio.
7.2.11, “Dither”, below), as this may help with dis-
tortion, though a little may be lost from the signal-
to-noise ratio.
7.2.11 Dither
Dithering, in digital audio, is the tech-
nique of adding a known noise signal to a low-
level input signal, especially when converting
from a word length with a higher number of bits
than the destination (see 7.2.10, “Word length”
above).
level input signal, especially when converting
from a word length with a higher number of bits
than the destination (see 7.2.10, “Word length”
above).
Paradoxically, this technique removes quantiza-
tion noise and improves overall distortion figures,
though at the slight expense of the signal-to-noise
ratio. The DA-38 implements an “on/off” dither
function, and the DA-98 allows two “shapes” of
dither. See section 4-8 of the DA-38 manual or
8.13 of the DA-98 manual for further details.
tion noise and improves overall distortion figures,
though at the slight expense of the signal-to-noise
ratio. The DA-38 implements an “on/off” dither
function, and the DA-98 allows two “shapes” of
dither. See section 4-8 of the DA-38 manual or
8.13 of the DA-98 manual for further details.
1) From menu group 1, move the cursor to
Dither
and press
SELECT
:
2) Allowable values for DA-38 units are
on
and
off
. The DA-98 allows the following settings
to be made:
off
,
triangular
and
rectangular
.
See the section 8.13 of the DA-98 manual for a
discussion of rectangular vs. triangular dither
modes.
discussion of rectangular vs. triangular dither
modes.
V a r i
S p e e d
M a c h i n e
1
F i x
+
0 . 0 %
NOTE
The varispeed function is only available if the unit clock has
been set to internal (see 7.2.6, “Clock selection”) and the
video resolve function (
been set to internal (see 7.2.6, “Clock selection”) and the
video resolve function (
) is
off.
I n p u t
S e l e c t
D i g i t a l
»
»
A n a l o g
»
»
»
»
M a c h i n e
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2
3
4
5
6
T D I F
W o r d
L e n g t h
M a c h i n e
1
1 6
b i t
D i t h e r
M a c h i n e
1
o f f
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38 98