Overview

DX & GX systems enable engineers to increase analogue and AES3 digital I/O in dLive, Avantis, AHM, SQ and Qu systems via the use of DX Expanders, GX Expanders and DX Distribution options.

The total number of processing channels in the system is determined by the processing core of the mixer. By adding DX & GX expanders, it is possible to:

Source all available input channels from analogue inputs
e.g. A Qu-5 has a 32 input channel core and 16 built-in preamps. Connecting a DX168 gives the system 32 freely patchable preamps.

Place I/O where it's needed
e.g. A dLive system may require 112 inputs on the stage, 16 inputs at the FOH position and 16 AES outputs at the amp rack.

Allow instant switching of sources
e.g. An Avantis may be using 96 inputs for a setup, but having many hundreds of sockets available means another setup can be physically connected and switched to instantly with a scene recall.

Transport signals that do not require processing
dLive, Avantis, AHM and SQ all include a Tie Lines feature, whereby any available input socket can be patched directly to any output socket, without using up any input or output processing channels. This is often used for communication lines, connecting audio between rooms in an install or for multichannel connections to external systems.

Protocols

The DX protocol carries 32x32 channels of 96kHz audio per DX connection.
Each DX connection can accommodate up to 2 DX expanders (1 DX32).

The GX and gigaACE protocols carry 128x128 channels of 96kHz audio per connection.
Each GX connection can accommodate 1 GX4816 expander, and additionally up to 2 DX32, or up to 4 DX expanders connected to the GX4816.

The ME and dSnake protocols carry 0x40 and 40x40 channels respectively of 48kHz audio per connection.
Each ME connection can accommodate an unlimited number of ME devices, via daisy chaining and/or a ME-U or PoE hub. The dSnake protocol is not compatible with any GX or DX expanders, though the DX 2 port of a GX4816 includes SRC and can be connected to an ME system.

Multiple DX and GX connections can be present in a dLive, Avantis, AHM, SQ or Qu system to massively expand the system analogue I/O.

SLink

The SLink port, found on Avantis, AHM, SQ and Qu mixers, is an intelligent multi-protocol port which supports DX, GX, gigaACE, ME and dSnake connections.

ⓘ AHM does not support ME connections.

ⓘ For more information on SLink, please refer to the SLink Connections article.

DX Expander Connectivity

DX32

The DX32 is a modular expander offering 4 slots, each being 8 channels of input or output, to fit a selection of analogue or AES3 digital I/O.

8 Channel Module Options

• M-AIN - 8 recallable preamps with XLR connectors for balanced or unbalanced microphone and line level signals. Gain, Pad and 48V Phantom Power are digitally controlled within the preamp.
• M-AOUT - Line level, balanced XLR outputs. The outputs are relay protected to prevent power on or off thumps.
• M-DIN - 4 Stereo AES3 Inputs on XLR with SRC (32kHz – 192kHz sampling rate). Sample rate conversion can be bypassed for 96kHz operation.
• M-DOUT - 4 Stereo AES3 Outputs on XLR (44.1kHz, 48kHz, 88.2kHz or 96kHz switchable).
• M-DX32-INPR – (PRIME IN) Premium 8 channel microphone preamp.
• M-DX32-OUTPR - (PRIME OUT) Premium 8 channel line-output.

The DX32 uses all 32x32 available channels of the protocol. Each module uses 8 input or output channels which are mapped by slot when patching at the mixer:

Slot 1 = Input or Output channels 1-8

Slot 2 = Input or Output channels 9-16

Slot 3 = Input or Output channels 17-24

Slot 4 = Input or Output channels 25-32

https://www.allen-heath.com/hardware/everything-i-o/dx32/

DX168

The DX168 is a fixed format expander offering 16 inputs and 8 outputs in a rugged stage box.

https://www.allen-heath.com/hardware/everything-i-o/dx168/

DX164-W

The DX164-W is a fixed format expander offering 16 inputs and 4 outputs in a wall mountable chassis.

https://www.allen-heath.com/hardware/everything-i-o/dx164-w/

DX012

The DX012 is a fixed format expander offering 12-16 outputs (depending on configuration) in a 1u rack mountable format.

https://www.allen-heath.com/hardware/everything-i-o/dx012/

DX88-P

The DX88-P is a fixed format expander offering 8 inputs and 8 outputs on Phoenix / Euroblock connectors in a half width 1u rack mountable format.

https://www.allen-heath.com/hardware/everything-i-o/dx88-p/

DX Cascade Mode

The DX168, DX164-W, DX88-P and DX012 all feature a Cascade mode, which allows 2 expanders to be daisy chained together on a single DX or SLink connection.

Any combination of two of these DX expanders is supported per socket in Cascade mode, with all inputs and outputs accessible to the mixer.

DX Expander 1

Mode = Cascade

DX A = Connect to SLink Port or DX Port (Surface, MixRack, DX Hub, DX Link)

DX B = Connect to the second DX expander

DX Expander 2

Mode = Cascade

DX A = Connect to the first DX expander

DX B = Disabled

Please refer to the table below for channel mapping, and patching at the mixer, when using DX Expanders in Cascade mode.

ⓘ Each cable can be 100m allowing 200m between DX socket and 2^nd device.

ⓘ DX32 Expanders do not support Cascade mode.

ⓘ Redundancy is not possible for DX Expanders in Cascade mode.
 

DX Redundancy

The DX32, DX168, DX164-W, DX88-P and DX012 Expanders can be connected in dual-cable redundant mode (32x32) to compatible hardware.

ⓘ SQ, Qu and AHM do not support DX redundancy.

dLive S Class Surfaces and MixRacks have integrated redundant DX sockets; DX1/2 & DX3/4 on the MixRack and DX5/6 on the Surface. They can also be used with DX Link and/or DX Hub options to add further redundant DX expanders.

dLive C Class Surfaces, C Class MixRacks and Avantis mixers can benefit from DX redundancy via the use of DX Link and/or DX Hub options.

DX Link features a Global Redundancy setting which allows 2 redundant DX streams (DX1/2 & DX3/4) per module:

Two DX Hub units can be used to achieve DX redundancy for up to 4 DX expanders. Both DX Hub units connect to a single gigaACE I/O module in a dLive or Avantis system:

DX Distribution Connectivity

The DX Link and DX Hub both offer 128x128 channels of 96kHz audio via 4 DX sockets, each capable of 32x32 channels of audio.

DX Link

DX Link is ideal for live music and theatre applications as well as any environment where the DX expander(s) are located within 100m of the dLive Surface, dLive MixRack or Avantis mixer.

• Installs into any I/O port in the system;
  • dLive Surface
  • dLive MixRack
  • Avantis Mixer

• 4 DX Link sockets – each 32x32 channels
• Switchable redundant mode (1/2 & 3/4)
• Up to 5 DX Link in S Class systems
• Up to 2 DX Link in C Class systems
• Up to 2 DX Link in Avantis systems
• 128x128 total DX channels per DX Link module

Up to 128x128 channels of DX expansion:

ⓘ Redundancy ON/OFF is global per DX Link module

https://www.allen-heath.com/hardware/audio-networking/dx-link/ 

DX Hub

DX Hub is particularly suited to Install and Commercial Audio applications and any environment where it is desirable to run a single “trunk” network cable to the DX Hub, from which DX connections can then be branched.

• Connects to:
  • dLive via gigaACE I/O module in dLive MixRack or Surface
  • Avantis via SLink socket and/or gigaACE I/O module(s)
  • AHM / Qu / SQ via SLink

• 4 DX Link sockets - 32x32 each
• Up to 5 DX Hub in S Class systems
• Up to 2 DX Hub in C Class systems
• Up to 3 DX Hub in Avantis systems
• Up to 2 DX Hub in SQ systems
• Up to 2 DX Hub in AHM 64 system, or 1 in AHM 16 or AHM 32 systems
• Use two DX Hubs for redundancy (dLive only)
• 128x128 DX channels per DX Hub module

Up to 128x128 channels of DX expansion

https://www.allen-heath.com/hardware/everything-i-o/dx-hub/ 

GX Expander Connectivity

GX4816

The GX4816 is a fixed format expander offering 48 inputs and 16 outputs in a freestanding or rack-mountable chassis. In addition, 2 DX expansion ports are provided with the second DX port capable of connecting to either DX expanders, or a ME Personal Mixing System.

The GX connection to the mixer is 128x128 channels, with the first block of 64x64 channels used by analogue I/O and ME channels, the next 32x32 channels used by the DX1 port and the final 32x32 channels used by the DX2 port (with DX expanders connected).

ⓘ DX1 and DX2 on the GX4816 cannot be used for redundant connections to DX expanders.

ⓘ When connected to a ME-U, ME-1 or ME-500, the DX2 port is self-configured as a 40ch, 48kHz, output only, port for the ME personal mixing system. Channel names and stereo links are communicated to connected ME systems. The ME patch in a Qu, SQ or Avantis will be automatically sent to this port and will override any output patch to DX2.

ⓘ ME connection via DX2 is not supported when connected to a dLive or AHM system.

ⓘ dLive compatibility with GX4816 requires firmware V1.86 or higher

https://www.allen-heath.com/hardware/everything-i-o/gx4816/ 

Connecting to dLive

S Class

DM0/DM32/DM48/DM64

Up to 448x448 channels of DX/GX expansion

https://www.allen-heath.com/hardware/dlive-series/dlive-mixracks/ 

S3000 / S5000 / S7000

Up to 288x288 channels of DX/GX expansion

https://www.allen-heath.com/hardware/dlive-series/dlive-surfaces/ 

C Class

ⓘ For DX redundancy with C Class hardware use DX Hub or DX Link options

CDM32 / CDM48 / CDM64

Up to 192x192 channels of DX/GX expansion

https://www.allen-heath.com/hardware/dlive-series/dlive-mixracks/ 

C1500 / C2500 / C3500

Up to 160x160 channels of DX/GX expansion

https://www.allen-heath.com/hardware/dlive-series/dlive-surfaces/ 

dLive & DX

All dLive Surfaces and MixRacks benefit from integrated DX sockets - dLive Surfaces offer 1 DX connection and dLive MixRacks offer 2 DX connections, with redundant sockets for dual-cable connection available on S Class hardware.

If further DX expanders are required, DX Link I/O modules and DX Hub remote hubs can be added to the system. Both provide 4x DX connections.

ⓘ A gigaACE I/O module is required for DX Hub connection

A fully expanded S Class system with 5 DX Hub/DX Link and 46 DX168 would add 736 inputs and 368 outputs to the system (DX Link shown in diagram)

A fully expanded C Class system with 2 DX Hub/DX Link and 22 DX168 would add 352 inputs and 176 outputs to the system (DX Link shown in diagram)

dLive & GX

1 gigaACE I/O module in the Surface or MixRack enables the connection of 1 GX4816 to a dLive system.

ⓘ dLive compatibility with GX4816 requires firmware V1.86 or higher

ⓘ ME connection to the GX4816 via DX2 is not supported when connected to a dLive system

Additional gigaACE I/O modules can be added for additional GX4816 connections, allowing up to 2 GX4816s on a C Class system, and up to 5 GX4816s on an S Class system.

ⓘ For information on supported DX and ME connections to a GX, please see the GX Expander Connectivity section.

Connecting to Avantis / Avantis Solo

Avantis

Avantis Solo

Up to 384x384 channels of DX/GX expansion

https://www.allen-heath.com/hardware/avantis/ 

Avantis & DX

The integrated SLink port on Avantis allows the direct connection of 1 DX32 or up to 2 other DX expanders.

Alternatively, a DX Hub can be connected to the SLink port, or a gigaACE I/O module, to provide 4 DX connections enabling the use of up to 8 DX expanders.

Up to 2 DX Link I/O modules, or gigaACE and DX Hub combinations, can be installed in the I/O ports to further expand DX connectivity up to a maximum of 24 DX Expanders

Avantis & GX

The integrated SLink port on Avantis allows the direct connection of 1 GX4816. An optional gigaACE I/O card can also be used for direct connection to a GX4816.

Connection of up to 3 GX4816s is supported via the use of both the internal SLink port and up to 2 gigaACE I/O modules.

ⓘ For information on supported DX and ME connections to a GX, please see the GX Expander Connectivity section.

Connecting to SQ / SQ+

SQ-5 / SQ-6 / SQ-7 / SQ-Rack / SQ5+ / SQ6+ / SQ7+

Up to 256x256 channels of DX/GX expansion

SQ & DX

The integrated SLink port on SQ mixers allows the direct connection of 1 DX32 or up to 2 other DX expanders.

Alternatively, a DX Hub can be connected to the SLink port to provide 4 DX connections enabling the use of up to 8 DX expanders.

An optional SLink I/O module can be installed in the SQ I/O port to enable further DX connectivity.

ⓘ SQ does not support DX redundancy

ⓘ DX32 support requires SQ firmware V1.4 or higher

SQ & GX

The integrated SLink port on SQ mixers allows the direct connection of 1 GX4816. An optional SLink I/O card can also be used for direct connection to a GX4816.

The connection of 2 GX4816s is supported via the use of both the internal SLink port and the optional SLink I/O module.

ⓘ For information on supported DX and ME connections to a GX, please see the GX Expander Connectivity section.

ⓘ GX4816 support requires SQ firmware V1.4 or higher

Connecting to Qu

Qu-5 / Qu-5D / Qu-6 / Qu-6D / Qu-7 / Qu-7D

Up to 128x128 channels of DX/GX expansion

https://www.allen-heath.com/hardware/qu/ 

Qu & DX

The integrated SLink port on Qu allows the direct connection of 1 DX32 or up to 2 other DX expanders.

Alternatively, a DX Hub can be connected to the SLink port to provide 4 DX connections enabling the use of up to 8 DX expanders.

ⓘ Qu does not support DX redundancy

Qu & GX

The integrated SLink port on Qu allows the direct connection of 1 GX4816.

Connecting to AHM

AHM-64

Up to 256x256 channels of DX/GX expansion

https://www.allen-heath.com/hardware/ahm/ahm-64/ 

AHM-16, AHM-32

Up to 128x128 channels of DX/GX expansion

ⓘ AHM-16 and AHM-32 require an SLink I/O Module to be fitted for any DX or GX connection.

https://www.allen-heath.com/hardware/ahm/ahm-16/ 

https://www.allen-heath.com/hardware/ahm/ahm-32/ 

AHM & DX

The integrated SLink port on AHM-64 allows the direct connection of 1 DX32 or up to 2 other DX expanders.

ⓘ AHM does not support DX redundancy

Alternatively, a DX Hub can be connected to the SLink port of an AHM-64 to provide 4 DX connections enabling the use of up to 8 DX expanders.

An optional SLink I/O module can be installed in the I/O port of any AHM-64, AHM-32 or AHM-16 for DX connectivity.

ⓘ Requires AHM firmware V1.2 or higher.

AHM & GX

The integrated SLink port on AHM-64 allows the direct connection of 1 GX4816. The optional SLink I/O module fitted to any AHM can also be used for direct connection to a GX4816.

ⓘ ME connection to the GX4816 via DX2 is not supported when connected to an AHM system.

The connection of 2 GX4816s is supported on AHM-64 via the use of both the internal SLink port and the optional SLink I/O module.

ⓘ Requires AHM firmware V1.2 or higher

Channel Mapping

DX Blocks of 16x16

Aside from the DX32, which takes up all 32x32 available channels, DX expanders are patched in blocks of 16x16.

When cascading 2 DX168s for example, the first DX168 will appear on input sockets 1 to 16 and output sockets 1 to 8, then the second DX168 will appear on input sockets 17-32 and output sockets 17-24. Leaving a 'gap' in the output socket patching from 9 to 16.

This method provides a number of benefits over concatenating sockets (as is done with the dSnake protocol):

• The first input and output socket on any expander in the system have the same socket number
• DX ports on DX Hub, DX Link or GX expanders always begin at the same socket number
• DX units with different I/O capabilities can be switched around or dropped in without needing to change the patch e.g. a DX168 and DX012 could be cascaded in either order and the first output socket on the second unit would always keep the same patch.
• Working out socket numbers when dealing with larger systems (e.g. up to 8 expanders via DX Hub or DX Link) is much easier

GX Blocks of 32x32

The DX Hub, DX Link module and GX4816 all use a 128x128 channel connection to the mixer. This is split into 4 32x32 channel blocks for each DX port of the DX Hub or DX Link module. The GX4816 works in a similar way, effectively using the first two blocks for its built-in analogue I/O and for ME channels, then the third block for the DX1 port and final block for the DX2 port.

DX Link and DX Hub

Please refer to the table below for channel mapping when using DX Expanders in conjunction with DX Link or DX Hub hardware.

dLive & Avantis: DX Hub & DX Link patching is performed on the I/O page under the appropriate I/O Port tab.

SQ: DX Hub patching is performed on the I/O page under the SLink or I/O Port tab.

Qu: DX Hub patching is performed on the I/O page under the SLink tab.

AHM: DX Hub patching is performed on the Assign page under the I/O Patchbay tab.

Cascade / Non-Redundant

Redundant

GX4816 – DX/ME Sockets

Please refer to the table below for channel mapping when using DX Expanders in conjunction with a GX4816.

dLive: GX4816 patching is performed on the I/O page under the appropriate I/O Port tab.

Avantis & SQ: GX4816 patching is performed on the I/O page under the SLink or I/O Port tab.

Qu: DX Hub patching is performed on the I/O page under the SLink tab.

AHM: GX4816 patching is performed on the Assign page under the I/O Patchbay tab.

ⓘ If a ME Personal Mixing system is connected to the DX2 socket on the GX4816, patching to the ME system is performed on the I/O page under the ME tab (all mixers).

ⓘ Connection of a ME system via DX2 is not supported on dLive and AHM systems.

Networking

The DX protocol is a Fast Ethernet point-to-point connection (100BASE-TX, IEEE 802.3u) and is Layer 2 compliant. Layer 2 network switches and media converters can be used, provided they support Fast Ethernet connections.

gigaACE, utilised by DX Hub and GX4816, is a Gigabit Ethernet point-to-point connection (1000BASE-T, IEEE 802.3ab), Layer 2 compliant. Layer 2 network switches and media converters can be used, provided they support Gigabit Ethernet connections.

General Rules

Layer 2.5 and higher protocols including Spanning Tree, Tagged Egress Packets, and Broadcast Storm Protection can cause interruption to audio data or audible clicks. Smart / managed switches may allow turning off Layer 3 or 4 functions, but as a general rule we recommend using Layer 2 devices only.

Note that no other network device should be plugged into a switch carrying gigaACE or DX audio unless a dedicated VLAN is set up.

Parallel connection of multiple DX Expanders on a switch is not possible.

When using an Ethernet switch or media converter, we suggest you check for errors and test for functionality and reliability before putting your system into service.

Cables

STP CAT5 (or higher) cables are required for 100Mbps connections to DX expanders.

STP CAT5e (or higher) cables are required for Gigabit connections, including the DX Hub and GX4816

STP CAT6a (or higher) cables are recommended for Gigabit (gigaACE/GX) connections to a Qu SLink port

ⓘ UTP cables are not supported

The maximum length of each cable is 100m*. With 2 DX expanders in Cascade mode this allows a distance of up to 200m between the SQ/Avantis/dLive and the second DX expander. Using a DX Hub allows for an additional 100m cable run between a gigaACE module or SLink port and the DX Hub giving a maximum distance of 300m between the mixer and the second DX expander.

*Or up to 80m for gigaACE/GX connections to a Qu SLink port.

Allen & Heath can supply a number of network cables as accessories - details available on our website.

VLANs

It takes some trial and error to configure a VLAN for use with DX or gigaACE, and the actual configuration depends on the specific switch in use. In our tests, we also found that many switches do not handle the gigaACE / DX packets with the time accuracy our clock requires, particularly over trunk lines and SFP modules, resulting in sync errors and in some cases, audible glitches. Thus, use of VLANs is not officially supported and the notes below are given as a guideline only.

One VLAN is needed for each point-to-point connection i.e. you cannot have more than two DX / gigaACE devices on the same VLAN. No other traffic should be present on this VLAN.

The ports should be forced to 100Mbps (Fast Ethernet) for DX / ACE / dSNAKE / ME, or Gigabit Ethernet for gigaACE / GX - we had mixed experiences with auto-negotiating ports. The ports need full 100Mbps / 1000Mbps bandwidth. This means that, in order to have a gigaACE VLAN on a switch, the trunk between switches must be higher than Gigabit (10 Gigabit recommended).

ALL Layer 2.5 and higher protocols must be disabled, as mentioned above. Essentially any packet on the VLAN other than audio transport is likely to cause audible glitches. The VLAN should be fully transparent to Layer 2 traffic, with no extra packet. Also note that dLive firmware prior to V1.8 had gigaACE fixed to VLAN 1, which would often conflict with the management VLAN on some switches. The VLAN tag was been removed in V1.8 allowing user tagging of gigaACE traffic.

Fibre optics

Most standard network to F.O. converters will work, provided they support the required connection type / speed (see above).