Lectrosonics Quadra - Manual (Page 5)

Digital IEM System
System Overview
The Quadra system provides an entirely new level
of audio and RF performance in a wireless monitor
system. The combination of analog or digital input
capability, ultra-low latency 24 bit, 48 kHz audio, digital
RF modulation and discrete four channel mixing capa­
bility make the Quadra a truly unique IEM product for
mission-critical, professional applications.
The system is designed for line level analog audio
signals and AES/EBU digital audio input signals.
48kHz/24-bit audio, ruler-flat 20Hz to 20kHz frequency
response, ultra-low distortion and high dynamic range
assure excellent audio quality. Housings and panels
are machined aluminum with electrostatic powder
coated and anodized finishes and laser etched mark­
ing for durability. An intuitive mixing interface and
comprehensive LCD on the belt pack receiver provide
performing artists and monitor engineers alike with a
comfortable and confident user experience.
M4 Transmitter
The half-rack transmitter can accept up to four inputs
from digital or analog sources. The inputs can be con­
figured as follows:
• Four analog inputs using all four jacks
• Two digital inputs using jack 1 and two balanced
analog inputs using jacks 3 and 4
• Four digital inputs using jacks 1 and 2
The input connectors are full size balanced XLR types
for AES/EBU and balanced line level analog signals.
Input preamp circuits use a special balanced amplifier
with very high common mode rejection to minimize
hum and noise.
Either analog or AES/EBU digital input signals are
converted to an internal 24-bit digital format which is
then encoded, organized into packets, and passed to
an RF modulator using spread spectrum techniques
and error correction for robust reception. The modu­
lated RF signal is filtered before and after amplification
to suppress out-of-band noise and spurious signals,
and a circulator/isolator guards against intermodulation
interference (IM).
The transmitter can be free-standing or rack-mounted
in single units (via an optional rack mounting kit) or in
a dual configuration using supplied hardware.
A USB port is provided for firmware updates.
M4 Receiver
The receiver employs advanced antenna switching
diversity reception, switching between the antennas
during packet headers in order to maintain a seamless
audio signal. A configurable four-channel mixer on the
top of the receiver housing allows the user to mix four
discrete audio channels according to the needs of the
performance. The headphone jack is fed from a high-
quality stereo amplifier with adequate power to drive
headphones or earbuds to sufficient levels for stage
performance or other environments with significant
background noise. A high-density, backlit LCD allows
the user to make setup changes via the available
menu options.
A USB port is provided for firmware updates.
Frequency Range
Using the license free 902 - 928 MHz ISM band, this
system is outside the normal broadcast frequencies
thus providing both technical and operational advan­
tages over standard analog systems.
OR
Freq 1 Freq 2 Freq 3 Freq 4
4 CHANNEL MODE
2 CHANNEL MODE
Freq
1A
Freq
2A
Freq
2B
Freq
3A
Freq
3B
Freq
4A
Freq
4B
OR OR OR
Freq
1B
In four-channel mode, the system occupies 4 MHz and
is selectable between four available center frequen­
cies: 907.776, 912.384, 916.992 and 923.904 MHz.
In two-channel mode, Quadra occupies 2 MHz and
is selectable between eight available center frequen­
cies: 906.624, 908.928, 911.232, 913.536, 915.840,
918.144, 922.752 or 925.056 MHz.
Multi-Channel Capability
Quadra can be configured to provide either 2 or 4
audio channels. In the 2-channel mode, eight different
frequencies are available, each with two audio chan­
nels. In the 4-channel mode, four different frequencies
are available, each with four audio channels. Multiple
Quadra systems can be operated in the same location
to provide up to 16 total audio channels between all
units.
The performer can then use the on-board mixer to tai­
lor the audio output to his or her tastes or the require­
ments of the performance at hand.
Rio Rancho, NM 5