LDD-1
AC -3/ RF De m o d ula to r
Use r G uid e
LDD-1
AC -3/ RF De m o d ula to r
Use r G uid e
Introd uc tion
Congratulations on your purchase of the Lexicon LDD-1. The LDD-1 is designed to interface between
a laser disc player (with an AC-3/RF output), and any Dolby Digital decoder which accepts a standard
AC-3 signal (like our DC-1). Because “AC-3 ready” laser disc players use a separate Radio Frequency
(RF) modulated output to carry the Dolby Digital information, special considerations must be made.
While this typeof transmissionworks perfectly well, our engineers were rightfully reluctant to inject line-
level RF directly into the meticulously designed DC-1. The solution is the LDD-1.
The LDD-1 keeps potential RF interference away from the sensitive preamp/processor stage while
providing highly useful improvements in AC-3 signal quality. By placing the requisite demodulation
circuitry in its own enclosure with dedicated power supplies and grounding, the potential to degrade
digital-to-analog conversion and analog audio signals within the preamp/processor is eliminated.
The LDD-1 incorporates fully automated “intelligent” switching between S/PDIF and AC-3/RF inputs,
meaning that any laser disc will be decoded to its maximum inherent quality. A low voltage “turn on
trigger” input andoutput are included for interconnectionto theLexicon DC-1and NT Series Amplifiers.
The stringently designed outboard power supply ensures maximum signal purity.
We have designed this manual to provide a brief overview of the demodulator, as well as to provide the
information necessary for safe installation and operation. We trust that the time you invest in reviewing
these brief instructions will be rewarded by the best possible performance and longevity of your
equipment.
1
Front Pa ne l
NOTE: When power is off, the LDD-1 automatically
outputs the COAXial digital input.
LOCK
This LED will light whenever the unit
sensesanAC-3/RFsignal. Whennosuch
signal is present, the LED will remain off,
POWER
This LED will light whenever power to
the unit is supplied and enabled.
and the INPUT SELECT LED will light.
2
LD OPTIMIZATION
INPUT SELECT
3-position switch which minimizes signal errors, pro-
viding optimal timing for specific brands of laser disc
players.
2-position switch for selection of the type of NON-AC-3/
RF digital output you are using from your laser disc
player.
Recommended Settings
High
Panasonic, Pioneer CLD-97 (MSB modified
version), Runco
Low
Denon, Enlightened Audio Designs, Pioneer
LD-S2 (MSB modified version)
Normal
Marantz, Mitsubishi, McIntosh, MSB, Theta,
Pioneer (including Elite), Yamaha
2
Re a r Pa ne l
Connections between the LDD-1 and associated
equipment should be made with all units UNPLUGGED!
RF IN
Connect this input to the laserdisc player’s RF/AC-3
output with a 75Ω coaxial cable. Keep this cable as
short as possible to minimize RF interference.
OUTPUT
ConnectthisS/PDIFoutputtoDC-1digitalinputCOAX1
POWER
with a 75Ω coaxial cable.
Connect the AC adapter here. Use only the supplied Lexicon
MSA AC adapter.
INPUT
LOOP THRU
S/PDIF INPUTS
Connect a 5-pin DIN cord (not supplied)
Allows the hook-up and power cycling of addi- Connectthis input to the laserdisc player’s NON-AC-3 digital
tional components such as the Lexicon NT output using the appropriate 75Ω coaxial cable.
Series of power amplifiers. Refer to the DIN
from this input to the DC-1 PWR CTL
Output. This allows the LDD-1 to power on
and off with the DC-1. If nothing is hooked
up here, the unit will turn on whenever the
AC adapter is supplied power. This set-up
allows use of a switched outlet or continu-
ous power. (As power consumption and
heat generation are both minimal, this will
not harm the LDD-1.)
Because you can switch between these inputs from thefront
panel, you may use both; which gives you an extra digital
input.
configuration diagram below.
1
2
3
=
=
=
Ground
Ground
Power On (constant
when the DC-1 is On)
Unused
4
5
=
=
Trigger (programmable)
3
4
The LDD-1 chassis is barely four inches deep to allow it to be positioned adjacent to an AC-3-capable
player’s RF output. This minimizes the required RF-signal cable length to reduce any RF interference.
As the unit uses automated switching, and draws very little power, you can literally set it and forget it.
Se tup
To set up the LDD-1:
•
Connect a 75Ω coaxial cable between the LDD-1 rear panel RF (AC-3) input and the laser disc
player's RF/AC-3 output. Keep this cable as short as possible to minimize RF interference.
•
Connect a 75Ω coaxial (or optical) cable between the LDD-1 S/PDIF input and the laser disc
player's digital output.
•
•
Connecta75Ω coaxial cable betwenthe LDD-1S/PDIF output andtheDC-1COAX1digital input.
Recommended: Connect a 5-pin DIN cord (not supplied) between theLDD-1 PWR CTL input and
the DC-1 PWR CTL output. This allows the LDD-1 to power on and off with the DC-1. If this
connection is not made, the LDD-1 will turn on whenever its AC adapter is supplied power.
•
•
Optional: Connect any additional components which allow remote turn on (such as Lexicon's NT
Series of power amplifiers) to the LDD-1 rear panel PWR CTL (LOOP THRU) connector.
Connect the AC adapter provided to the POWER jack.
Once the LDD-1 is properly connected, set the front panel INPUT SELECT switch for the appropriate
type of NON-AC-3/RF digital output you are using on your laser disc player. (Most laser disc players
haveonly one.) Set theLD OPTIMIZATION switchaccordingtothechart providedonpage2. Onceyou
have completed the connections and setting of the front panel switches, all functions are performed
automatically. LEDs on the front panel are provided to identify the operational state.
Ma inte na nc e
TheLDD-1requiresnomaintenance. However,itis goodelectricalpracticetocleanallconnectorsonce
a year. Clean the exterior surfaces of the unit with a soft, lint-free cloth, dampened with warm water.
5
Sp e c ific a tions
Inputs
2: 1AC-3/RF via COAX; 2 Digital (1 COAX; 1 Optical)
Outputs
Optimization
One (1) Digital via COAX
3-position toggle switch, decoder pulse settings
Controls and Indicators
LEDs indicate operational status
Toggle switches for: LD Optimization: High, Low, Normal; Input Select: Optical, COAX
Connectors
General
Inputs: 4: 2 RCA (COAX); 1 TOSLINK (Optical); 1 5-pin DIN (PWR CTL)
Outputs: 2: 1 RCA (COAX); 1 5-pin DIN (PWR CTL Thru)
Power connector: 2.5mm, 9VAC, 1A
Dimensions: 17.0"X x 1.75"H x 4"D
Weight: 2.4 lbs net; 4.4 lbs shipping
Power Requirements: 120VAC, 60Hz or 230VAC, 50Hz. Use Lexicon MSA AC Power Adapter.
Rack mount adapters are available through your Lexicon dealer.
All specifications subject to change without notice.
Lexicon Inc.
3 Oak Park
Bedford MA 01730-1441
Telephone 617-280-0300
Fax 617-280-0490
Lexicon Part # 070-11659 Rev 1
Printed in U.S.A.
|