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3 - menu functions, 19 3.6 digital output format, 7 digital out word length – Tascam DA-45HR User Manual

Page 19: 8 dither, 9 copy prohibit, 10end id

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3 - Menu functions

TASCAM DA-45HR

19

3.6 Digital output format

Sets the format of the digital audio data output from
both digital audio outputs (the

AES/EBU

XLR con-

nector and the

COAXIAL

RCA connector).

The options available are

AESEBU

(AES/EBU

format) and

Consmr

(SPDIF format).

The default is

AESEBU

.

3.7 Digital out word length

When a tape has been recorded in

HR(24BIT)

mode,

it may be necessary to play back the material at 16-
bit resolution.

Note that the format of the digital audio data will
always be output in the format as selected above (3.6,
"Digital output format") from both connectors (

AES/

EBU

and

COAXIAL

).

The options available are

24bit

and

16bit

.

The default value is

24bit

.

3.8 Dither

Dithering is the technique used to improve resolution
at low levels, with resulting loss of quantization
noise

1

. It is particularly useful when playing back

audio recorded with higher number of bits than the
destination is capable of receiving.

When playing back a recording made in 24-bit HR
mode, dithering may be used if the internal D/A con-
vertors are used. There is no effect if dithering is
selected, and 16-bit output word length is selected.

In the STANDARD mode, any dither settings made
are applied to the signal as it is recorded.

The triangular (

Tri.

) setting reduces noise more

effectively than the rectangular (

Rect.

)

2

, but

both reduce the signal-to-noise ratio compared to the

off

setting, triangular more than rectangular.

There is no rule for using dither—different circum-
stances demand different settings.

The default setting here is

off

.

3.9 Copy prohibit

Sets the level of copy protection for tapes recorded
using this tape deck.

The menu items control the writing of the copy pro-
tection bit in the subcode of the recorded material.
The options available are:

Free

(no copy protec-

tion is applied to the recorded material),

1gen

(one generation only of digital copying is possible
from tapes produced when this setting is made), and

Prohbt

(no digital copying at all is possible).

The second option is equivalent to the SCMS system
implemented on consumer DAT recorders.

The default value here is

Free

.

3.10End ID

Sets whether an END ID is automatically written
whenever recording stops.

The two options available are:

No WR

(no END

ID is written when recording stops) and

AutoWR

(an END ID is automatically written when recording
stops). When an END ID is written, the display
shows

WR-EE

.

When playing back and an END ID is encountered,

EE

is shown on the display, and playback stops. The

tape then either stops or rewinds, depending on the
setting made in 3.15, "Auto rewind".

The default value is

No WR

.

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1.

A full disc

ussion of dither and other digital

audio techniques is outside the scope of this
manual. However, a good starting point for
learning about this, and other aspects of digital
audio, is John Watkinson’s The Art of Digital
Audio
, pub Focal Press

2. These names refer to the shape of the proba-

bility curve describing the noise applied to the
original signal as part of the dither process.

C

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