Reference Manual
Rio Rancho, NM 5
General Overview
As digital technology continues to advance in a va-
riety of markets and products, considerable benefits
also evolve in audio processing systems for installed
sound systems that employ multiple microphones and
loudspeakers in a common acoustical space. The
DM Series digital processors take advantage of these
advances with hardware/software designs that address
modern applications in boardroom, courtroom, sound
reinforcement and teleconferencing systems.
The latest generation DSP microchips and microproces-
sors are the core of the engineering of the DM Series
products. The focus and purpose is to meet the require-
ments of modern applications and also the demands for
convenience and automation.
The DM can be configured either via a front panel
mounted LCD and controls, or LecNet2™, a user-
friendly, yet powerful control program. LecNet2™ offers
quick configuration and full command of the system
through a USB or RS-232 compatible interface. Once
configured, the units operate independently.
All models in the DM Series offer the same signal pro-
cessing functions, and vary only by the number of audio
inputs and outputs available. The DM’s basic structure
consists of three stages: Input, Matrix and Output.
(See DM1624F Signal Flow Block Diagram below and
DM1624F Functional Block Diagram .)
Each input channel includes a high quality analog
preamplifier, with digital and analog level control to
maximize signal to noise ratio and minimize distortion,
followed by a 24-bit A-D converter. Extensive digital
signal processing is provided on each input channel.
Each input channel is processed and filtered as needed
and the signal is delivered into the matrix.
The digital matrix mixer distributes each input signal to
any selected combination of outputs, with level control
at each crosspoint. The matrix processes the signals
and delivers them to the assigned outputs and com-
municates with other devices in the system. Each
output receives signals from the mixing matrix, the pink
noise generator or the tone generator as needed for
setup, diagnostics or operation. Each of the 24 outputs
includes extensive signal processing to optimize the
mixed signal for the intended purpose, such as sound
reinforcement, recording or teleconferencing.
Multiple units can be stacked together using the Digi-
tal Audio Network Interface (DANI). DANI connects
the digital audio outputs of the master and slave units
through standard RJ45 connectors.
When multiple units are stacked, mixing data and the
digital audio are passed between the slave units and
the master unit through the DANI. Multiple units can be
stacked in a master/slave configuration to expand the
number of inputs to hundreds of channels.
The audio and data from all units in the stack are gath-
ered in the matrix in the master unit, which is where the
final mix signals are generated. The first 12 final mix
signals from the master are back propagated through
the DANI to each slave. (See DM Series Back Propa-
gation Diagram.) These signals are available on the
slave unit outputs 1 through 12. If a slave unit is also a
DM1624F, outputs 1 through 12 are also repeated on
outputs 13 through 24. Each output channel on a slave
unit retains its own processing (filters, compressor, etc.)
even though the signal mix is the same as that channel
on the master unit. (See diagram on page 12).
DM1624
Master
DM1624
Slave
DM1624
Slave
1
24
Outputs
DM1624 Master
with
DM1624 Slaves
DM1624
Master
DM1612
Slave
DM812
Slave
1
24
1
12
1
12
Master and
Slave Outputs
Outputs
Outputs
DM1624 Master
with
DM1612 or DM812 Slaves
12
13 Master only
Outputs
DM1612
Master
DM1612
Slave
DM812
Slave
1
1
12
1
12
Outputs
Outputs
DM1612 Master
with
DM1612 or DM812 Slaves
12
Outputs
1
Outputs
12
Outputs
1Outputs
12
1(13)
12(24)
Outputs
1(13)
12(24)
16 by 24+2
Automatic
Mixing
Matrix
Input #1
Processing
Input #16
Processing
Output #1
Processing
Output #24
Processing
Tone
Generator
1 kHz, 0 dBu
Pink Noise
Generator
0 dBu
24 Output Submixes
2 Expansion Submixes
26 Automixing Aux. Data
2 Expansion Signals
26 Automixing Control Data
24 Output Submixes
2 Expansion Submixes
26 Automixing Aux. Data
2 Expansion Signals
26 Automixing Control Data
.
.
.
.
.
.
DM1624F Signal Flow Block Diagram
(Typical of DM Series)
