6 Input, 4 Output Audio Expansion Processor with AEC and Dante
Key Features
  • Six mic/line level inputs for transmitting audio to a Dante network
  • Four independent channels of AEC - acoustic echo cancellation
  • Four inputs with FlexInput capability to select between analog or Dante inputs
  • Four line outputs receive audio from a Dante network
  • Dante audio networking provides a wide range of expansion capabilities
  • Built-in four-port Gigabit switch
The Extron AXP 64 C AT
Model Version Description Part #
 AXP 64 C AT 6 In, 4 Out Expansion Processor 60-1499-01

The Extron AXP 64 C AT is an audio expansion processor with six mic/line inputs and four line outputs for remote connectivity to a Dante®-enabled audio system. It is used to place six mic/line sources onto a Dante audio network, and route any four Dante channels from the network to an amplifier or other destination. The AXP 64 C AT features Extron ProDSP™ with gain, filtering, and dynamics processing for all inputs and outputs. Four of the inputs also include AEC, 48 volt phantom power, and dedicated control ports for mic control. FlexInputs offer the additional capability to process Dante channels in place of local analog inputs 1 - 4. A single Ethernet cable from one AXP 64 C AT, or several linked units, to a central equipment rack greatly reduces the effort and expense of pulling one cable for each endpoint.

Remote Input and Output Expansion with Processing

The AXP 64 C AT accepts six channels of balanced or unbalanced analog audio, four with 48 volt phantom power, and digitizes them at 24-bit/48 kHz for output via Dante. The AXP 64 C AT includes four independent channels of AEC with advanced algorithms for fast convergence and optimal intelligibility in conferencing applications. For remote processing of Dante audio network signals, inputs 1 - 4 can access any Dante channel on the network. When compared to a conventional input expander or break-in box, the AXP 64 C AT is truly unique in that it incorporates DSP for each input channel. This makes it much simpler and less expensive to expand input channel capacity by avoiding the need to install a remote break-in box plus additional DSP hardware at the central rack, which may otherwise be underutilized.

Each input is routed directly to the Dante network for routing to any Dante-enabled device such as the DMP 128 Plus AT or DMP 128 C P AT. For conferencing applications where a pre-processing feed is required, inputs 1 - 4 also offer a post-filter/pre-AEC output to the Dante network.

The AXP 64 C AT can convert four Dante channels and route them to the four line level outputs. This enables audio from the Dante network to be sent to a sound reinforcement system or other audio destination. The AXP 64 C AT provides dedicated filtering, dynamics, and delay processing for the line level signals to optimize the audio for the local environment.

A sound system designer can incorporate several AXP 64 C AT or AXP 50 C AT audio expansion processors to create a large mixing matrix with up to 48 remote inputs and 24 outputs per DMP 128 Plus AT. Each AXP product is connected over Ethernet using standard IP networking protocols. This greatly simplifies scalability and the audio cabling infrastructure. Utilizing the Dante network also avoids a long analog mic cable run for each endpoint and the possibility of introducing noise into the system. For further convenience, multiple AXP Series and DMP 128 Plus AT units can be linked over their integrated four-port Gigabit switches.

FlexInput Channels

The four AEC-enabled inputs on the AXP 64 C AT offer FlexInput capability to route a Dante channel in place of a local mic/line input. The flexible input selection enables the AXP 64 C AT to process audio from remote wireless microphones, wallplates, and other sources from anywhere on the Dante network.

Convenient Under-Table and Surface Mounting

The AXP 64 C AT is housed in a compact 1U, half rack width enclosure that can be installed underneath a conference table or inside a credenza near microphones, sources, and remote audio destinations. Optional Extron UTS Series or MBU 123 mounting hardware is available separately to facilitate under-table and surface mounting.

Acoustic Echo Cancellation at the Source

The AXP 64 C AT includes four independent channels of Extron AEC for conferencing applications. An AEC reference signal is provided over the Dante network by a DMP 128 Plus C AT. AEC is essential for effective room-to-room conversations, ensuring clear, natural communication for all participants. Each AEC processor in the AXP 64 C AT includes selectable noise cancellation. The AXP 64 CAT provides up to 20 dB of noise cancellation without noticeable artifacts, for unparalleled performance and increased intelligibility to the far end. 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.

Flexible Signal Routing

The internal DSP architecture of the AXP 64 C AT sends both pre- and post-processing input feeds for the first four input channels onto the Dante network. The last two channels offer post-processing feeds to the Dante network. This provides the flexibility to limit the signal processing on mic input signals for recording, assistive listening, or voice reinforcement feeds, while applying full processing and AEC to a conferencing application. Filter blocks are situated prior to the pre-processing outputs, applying low frequency roll-off to attenuate breath and wind noise and other EQ settings, while bypassing the AEC. For conferencing applications, AEC processing, together with dynamics and EQ, is an absolute necessity to ensure optimal audio quality to the far end.


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, AEC, dynamics, and filters.

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 processing tools for the AXP 64 C AT, including gain, filters, and dynamics for each input and output, plus AEC for inputs 1 - 4. Designers can quickly get a snapshot of the entire audio system, including processing blocks and signal paths, all at once.

Dante Audio Networking

Dante enables audio system scalability over a local area network using standard Internet protocols. A built-in four-port Gigabit switch provides direct interconnection of multiple AXP Series and DMP 128 Plus AT units to create larger, cost-effective audio matrixes. Additionally, the AXP 64 C AT can be configured to support primary and redundant Dante audio networks.

Setting up a network of Extron Dante-enabled products, including the AXP 64 C AT, requires Dante Controller software, as well as the DSP Configurator Software. Dante Controller is used to easily assign an output from the AXP 64 C AT to inputs on DMP 128 Plus AT units or third-party devices. Dante Controller is also used to assign Dante channels from the network to the four digital FlexInputs of the AXP 64 C AT, for processing and routing Dante channels for local sound reinforcement systems via its physical outputs, and to assign the four AEC reference inputs for the processor.


Control and configuration are conveniently available via the built-in four-port Gigabit switch. Any port can be designated for control only. The AXP 64 C AT includes digital I/O ports for inputs 1 - 4, which allow for external triggering such as mic activation and muting, and illuminating status LEDs.