Home Theater Audio Delay Corrector
Digital Audio Delay Corrector
The Master Delay Box DD740
is designed to restore perfect lip-syncing to the audio output from your
digital satellite receiver and DVD-player. Modern
displays, such as plasma screens, LCD screens and projectors use sophisticated
imaging processors to produce the best picture possible. This processing takes
time and produces a delay in the picture display. This is called a Lip-Sync
Error. This is particularly noticeable in speech, where the voice comes first and
the lips move after. Lip-syncing anomalies may also affect satellite broadcasts
and can occur when the transfer of older movie soundtracks to digital surround
sound for DVD. The effect can be so pronounced that the film or broadcast
becomes difficult to watch. With DD740 you have total control over Audio/Video
synchronization and by delaying audio to match the video delay, you can enjoy
the Home Theatre Experience.
DD740 has 4 Input Channels and 2 Output Channels. The Delay Box has a total
delay of 0 – 680ms @ 32KHz / 48KHz sample rate, or 0 – 340ms @ 96KHz sample
rate. The delay can be programmed in steps of either 1ms or 0.33ms (Fine Mode).
DD740 allows storage of up to 36 Preset delay settings, 9 for each input
channels. All operations can be easily performed either on the stand-alone
device or using the remote control provided along with the device.
The device works seamlessly with your audio output from each of your
sources connected to the Digital Audio Inputs (A, B C or D). If you are
connecting an analog (stereo) audio source, make sure you use a third-party
Analog-to-Digital Audio Converter to convert into digital audio before
connecting it to the DD740.
The Delay Box can receive audio inputs either using a TOSLINK (A or C) or
COAX (B or D). Connect one of the DD740’s outputs TOSLINK (A) or COAX (B) to
the corresponding input on AV Receiver. Single connection is sufficient because
the DD740 serves as a four input switcher and outputs the selected input (A, B,
C or D). However, both the TOSLINK and the COAX outputs can be connected to the
receiver. When power is connected between the device and the wall socket, DD740
will enter STANDBY MODE. In standby mode, the digital audio signal on the
selected input passes through the DD740 without any delay being applied.
Input/Output conversion between COAX and TOSLINK remains active during standby
mode. Pressing the POWER button (either on the Front Panel or on the Remote
Control), will switch the device to active mode and delay the digital audio by
the set amount of time as displayed. To return back to the STANDBY MODE, press
the POWER button again, but keep the power adaptor plugged in.
Certain AV processors have corrective circuitry in-built, but experience
has shown that these processors work best with a signal that is already
synchronized. By inserting the DD740 between source and processor, advanced
digital synchronization can be achieved by tiny increments as fine as 0.33ms,
which results in a perfect sound and
Standby Mode is
indicated by a single light – either Input A, B, C or D – being lit while the
rest of the Display remains blank. In Standby Mode, the digital audio signal on
the selected input passes through the DD740 without any delay being applied. Input/Output
conversion between COAX and TOSLINK remains active during Standby Mode.
standby mode, pressing the POWER button (either on the Front Panel or on the Remote
Control), will switch the device to Active Mode and the delay displayed will be
applied to the selected input signal before it appears on the DD740’s output.
To return back to standby
mode, press the POWER button
SELECTING THE INPUT SOURCE
be selected in either Standby Mode or Active Mode.
Press InA, InB, InC or InD. The selected input will appear briefly on the
DD740 display and corresponding input indicator light will illuminate and
remain lit as long as the input remains selected.
METHOD 2 (Remote Control or Front Panel Buttons):
Press and release INPUT/MENU. The current input selection will
appear on the display. To change the input, press and release INPUT/MENU until the required setting is reached.
The input setting will remain selected until it is changed, even if power is
lost to the DD740.
applied to the selected signal is shown on the DD740 display in milliseconds
(ms). Press DELAY+ button
increase the delay and the DELAY- button to decrease the delay.
can be set to any time between 0 – 600ms for 48KHz audio and 0 – 340ms for
96KHz audio. The delay is set independently for each input. If the input is
changed the delay will revert back to the setting that was last used for that
NUMERIC DELAY ENTRY (Remote Control):
keypad can be used to set the delay directly. Enter the desired delay by
pressing the number buttons in sequence and the delay will be set after a brief
pause following the last digit entered.
FINE DELAY ADJUSTMENT MODE (0.33ms INTERVALS):
Delay can be increased
in intervals of 0.33ms in Fine Delay Adjustments Mode. To enter Fine Adjustment
Mode, press DELAY+ then DELAY- in quick succession.
Following this, delay can be increased by
0.33ms by pressing the DELAY+ button and can be
decreased by 0.33ms by pressing the DELAY- button. Although the delay changes by 0.33ms, the display continues to
show delay in whole milliseconds.
After 5 seconds, if no buttons are being
pressed, DD740 returns to normal mode where the delays are changed in increments
allows storage of up to 36 delay settings for easy recall, 9 for each input.
Each of these delays are held in a preset settings – PA1 through PA9 (for Input
A), PB1 through PB9 (for Input B), PC1 through PC9 (for Input C) and PD1 through
PD9 (for Input D).
Presets are stored and recalled using the
buttons on the Remote Control. Presets are retained in the internal memory even
if the power to the DD740 is lost.
DELAY IN A PRESET (Remote Control):
required delay (ms) by pressing the corresponding numbers on the remote
Press STORE button.
recent preset setting used for the selected input will appear and start
flashing on the DD740 display.
Select the Preset to
hold the delay by using the PRESET+ and PRESET- button on the Remote Control.
Press STORE button once more.
The Preset will stop
flashing, indicating that the delay is stored in the Preset selected.
After a couple of
seconds, the delay will reappear on the DD740 display.
DELAY FROM A PRESET (Remote Control):
Presets can be recalled using the Preset buttons, P1 through P5 on the Remote.
stages 1 through 5 for the most common delay setting.
also be selected by pressing the PRESET+ or PRESET- on the Remote.
button when the required Preset setting appears on the screen.
delay for the selected Preset setting will be displayed after a couple of
CHANGING DISPLAY BRIGHTNESS
of Brightness are available between br1 (dimmest) and br5 (brightest).
Press and release the BRIGHTNESS button until you achieve the brightness
required. The new brightness setting will be displayed briefly.
(Remote Control or Front Panel Buttons):
Press and hold INPUT/MENU button for approximately 5 seconds. The
current Brightness setting is shown on the display screen.
While the Brightness
level is being displayed, change the Brightness using the DELAY+ and DELAY- buttons till the desired Brightness is achieved.
With the required
Brightness level selected, wait for approximately 5 seconds to exit the menu.
Alternatively, pressing the INPUT/MENU button will exit the
– 680ms in 1ms or 0.33ms increments (32/48 KHz)
– 340ms in 1ms or 0.33ms increments (96 KHz)
Digital Audio Signal Compatibility: S/PDIF Digital Audio on
both COAX and TOSLINK
Connections: INPUT: 2 x RCA Socket (75Ω, 0.5V(p-p))
x Optical Socket
OUTPUT: 1 x RCA Socket (75Ω, 0.5V(p-p))
X optical Socket
Power Requirements: 9V DC, < 200mA
x 4.10” x 1.40”