DMP 128

12x8 ProDSP™ Digital Matrix Processors
Key Features
  • Six models with 12 mic/line inputs and 8 outputs
  • Models available with AEC, Dante®, and POTS
  • Eight channels of AEC - acoustic echo cancellation
  • Eight inputs with FlexInput capability to select between analog or Dante inputs on DMP 128 AT models
  • Dante audio networking provides a wide range of expansion capabilities
  • Digital audio expansion port for linking two DMP 128 units
The Extron DMP 128
Model Version Description Part #
 DMP 128 12x8 ProDSP Processor 60-1211-01
 DMP 128 C P 12x8 ProDSP Proc. w/AEC and POTS 60-1179-01
 DMP 128 C P AT 12x8 ProDSP Proc. w/AEC, POTS and Dante 60-1179-10
 DMP 128 C 12x8 ProDSP Proc. w/AEC 60-1178-01 Retired
 DMP 128 C AT 12x8 ProDSP Proc. w/AEC and Dante 60-1178-10 Retired
 DMP 128 AT 12x8 ProDSP Processor w/Dante 60-1211-10 Retired

The Extron DMP 128 Digital Matrix Processor is a 12x8 audio mixer featuring Extron ProDSP™, automixing, available AEC plus Dante® audio networking, FlexInputs to process Dante channels in place of local mic/line inputs, and POTS analog phone interfacing. The DMP 128 Series offers a configuration approach to DSP that simplifies mixing, routing, conferencing, and room optimization. Quick and intuitive configuration using the DSP Configurator™ Software allows the DMP 128 to be installed in very little time, with easy-to-learn adjustments that can be heard in real‑time. A digital audio expansion port allows two DMP 128 units to be linked together to expand input and output signal management and routing capabilities. The DMP 128 is ideal for presentation and conferencing applications in boardrooms, courtrooms, and conference centers.


Extron’s exclusive ProDSP is engineered from the ground up using a powerful 64‑bit floating point DSP engine to provide very wide dynamic range and reduce the potential for clipping. ProDSP also utilizes studio grade 24‑bit audio converters with 48 kHz sampling to maintain audio signal transparency. ProDSP is loaded with powerful, easy‑to‑configure tools to control level, dynamics, filters, delay, ducking, loudness, and feedback suppression.

Easy-to-Use DSP Configurator Software

The power of ProDSP is easily harnessed with the DSP Configurator Software. The flexible on‑screen layout offers fast access to all of the digital audio signal processing tools including level control, dynamics, filters, delay, ducking, loudness, feedback suppression, and matrix mixing. Designers can quickly get a snapshot view of the entire audio system, including processing blocks and routing assignments, all at once.

Flexible Routing Within the DMP 128

The DMP 128 features 12 mono mic/line inputs, eight with phantom power. These inputs can be matrix mixed into any of the eight output buses to create finely tuned audio zones for the corresponding outputs. In addition, the 12 inputs can also be routed to any of the eight “virtual” buses to allow inputs to be processed together as a group, before routing back into the output buses. If desired, input signals can be mixed with signal processing or automixing bypassed. The flexible routing and mixing capabilities within the DMP 128 allow system designers to create simple or complex signal management schemes to accommodate a wide variety of sound system application requirements.

Expanded Routing Across Two DMP 128 Processors

An expansion port allows any two DMP 128 models to be linked together via a single shielded CAT 6 cable. This allows eight matrix mixes of the inputs, plus eight virtual paths to be sent and received between units, for a total of 16 incoming and 16 outgoing buses. Each bus carries 24‑bit/48 kHz high resolution digital audio within the DMP 128. This expanded 16x16 I/O channel transport between devices allows designers to create audio mixes with advanced I/O and signal management scenarios combining the capabilities of two DMP 128 processors. The expansion port is also available on Extron DTP CrossPoint® matrix switchers. This allows an 8x16 I/O channel transport between the matrix switcher and the DMP 128 to expand the number of available audio inputs for a DTP System, and to offer additional capabilities such as automixing, AEC - acoustic echo cancellation with DMP 128 C models, and POTS analog phone interfacing with DMP 128 C P models.


The DMP 128 features an automixer with gated and gain sharing modes for managing up to eight groups of microphone signals. Gating threshold, signal level reduction, and timing parameters are user-adjustable per channel. This allows for fine-tuning to avoid the “chopped” sound characteristic of a traditional automixer when a mic is gated off. As the number of active microphones is doubled, system gain is automatically reduced by half, uniformly attenuating microphone signal levels to minimize audible changes in the overall sound and the possibility of feedback. For a natural sounding mic mix, the automixer also offers a gain sharing mode when the NOM - number of open microphones is bypassed, allowing all mics to gate on. When a DMP 128 is linked to another unit through the expansion port, each incoming expansion bus can be assigned to an automixer gating group.

Acoustic Echo Cancellation

The DMP 128 C and DMP 128 C P models include Extron AEC for conferencing applications. AEC is essential for effective remote room-to-room conversations, ensuring clear, natural communication for all participants. These models include eight independent channels of high performance AEC, as well as selectable noise cancellation. AEC processing can be challenged by conditions such as double-talk, when talkers from both ends are speaking simultaneously, and when near end talkers use wireless microphones. Extron AEC features advanced algorithms that deliver fast echo canceler convergence for optimal intelligibility, even in challenging conditions.

The DSP Configurator Software simplifies AEC and noise cancellation setup with a user-friendly interface that provides real-time metering for ERL - echo return loss, ERLE - echo return loss enhancement, and TER - total echo reduction levels. Guided alerts appear whenever ERL is outside of the optimal range for echo cancellation. Optional settings include fine adjustments for NLP - non-linear processing to maximize AEC performance in acoustic environments with significant sonic reflections or reverberation.

FlexInput Channels on DMP 128 AT Models

Inputs 1 - 8 on Dante-equipped DMP 128 AT models offer FlexInput capability to route a Dante channel in place of a local mic/line input. The flexible input selection enables the DMP 128 AT to process audio from remote wireless microphones, wallplates, and other sources from anywhere on the Dante network. This allows incorporating the full range of DSP capabilities, including AEC, for incoming Dante channels.

Dante Audio Networking

Dante-equipped DMP 128 AT models provide scalable audio transport over a local area network using standard Internet protocols. Each DMP 128 AT sends out 24 channels of digital audio and can receive 56 channels over the network. A built-in four-port Gigabit switch also provides direct interconnection of multiple DMP 128 AT processors, plus AXP 50 C AT and AXP 64 C AT expansion processors to create larger, cost-effective audio matrixes. Additionally, the DMP 128 AT can be configured to support primary and redundant Dante audio networks.

Setting up a network of Extron digital audio processors requires Dante Controller software, in addition to the DSP Configurator Software. Dante Controller is also used to assign Dante channels from the network to the eight digital FlexInputs of the DMP 128 AT, for processing and routing Dante channels for local sound reinforcement systems via its physical outputs.

POTS Analog Telephone Capability

DMP 128 C P and DMP 128 C P AT models provide the ability to answer and initiate telephone calls to remote participants in a conferencing session. Two RJ-11 ports allow connection to a POTS line and a telephone handset. DMP 128 P models can be used over the PSTN - public switched telephone network and in a PBX - private branch exchange, and comply with all applicable US and international standards. The DSP Configurator Software facilitates quick and intuitive telephone setup, and includes a convenient phone dialer interface for setup and testing.

Extron recommends applying factory-configured Building Blocks to the telephone input and output channels. These Building Blocks allow fast and easy configuration of DSP settings for incoming and outgoing telephone signals, and help ensure optimal voice intelligibility, low noise, and protection from extremes in signal levels.

Versatile Control Options

The DMP 128 can conveniently be controlled and configured via RS-232 serial control, Ethernet control, or USB. It also includes digital I/O ports, which allow for external triggering such as mic activation and muting.