Allen & Heath AHM-64 audio matrix processor: rear panel, wiring and setup guide
The AHM-64 is a 2U audio matrix processor for installs: paging, zoning, conferencing and speaker processing. It has 12 mic/line inputs and 12 line outputs on Phoenix connectors, a built-in SLink port for expanders, a 2 x 2 GPIO, a control network port, a 12V DC backup input and an I/O Port slot for Dante or more expansion. Click any connector on the panels below to see what it does.
- 2U rack mount
- 12 x mic/line in (Phoenix)
- 12 x line out (Phoenix)
- 64 x 64 matrix
- SLink 128 x 128
- I/O Port slot
- DC backup power
AHM-64 specifications
| Model | AHM-64 |
| Form factor | 2U, 19 in. rack mount or free standing |
| Dimensions (W x D x H) | 482.6 x 364 x 91.2 mm (19 x 14.3 x 3.6 in.) |
| Weight | 7 kg (15.5 lb) |
| Processing matrix | 64 x 64 |
| Local analogue I/O | 12 mic/line inputs, 12 line outputs |
| Zones | Up to 64 mono or stereo |
| SLink | Built-in, up to 128 x 128 |
| I/O Port | Option card slot, up to 128 x 128 |
| Mic/line inputs | Balanced, recallable preamps, +5 to +60 dB gain, -20 dB pad, +48V |
| Line outputs | Balanced, +4 dBu nominal, +22 dBu max, relay protected |
| GPIO | 2 inputs (switch to ground), 2 relay outputs, +10V DC out (200 mA max) |
| Control | Gigabit RJ45 network port |
| Sample rate | 96 kHz |
| Playback | About 3 GB internal storage, WAV, MP3 and FLAC |
| Mains power | 100 to 240V AC, 50/60 Hz, 70 W max, IEC inlet |
| DC power | 12V DC backup, 5 A minimum, 8 A maximum supply |
| Operating temperature | 0 to 40 °C (32 to 104 °F) |
| Default IP address | 192.168.1.90 (subnet 255.255.255.0) |
Every connector on the AHM-64, explained
Click a card to light up those connectors on the panels above.
12 line outputs and 12 mic/line inputs24 on the panel
The top of the rear panel is one long row of 3-pin Phoenix sockets. The left half holds Line Outs 1 to 12, the right half holds Mic/Line Ins 1 to 12. The drawing staggers them in two rows so each socket can be clicked; on the unit they sit side by side in groups of three.
Each input is a recallable preamp with gain, pad and 48V phantom power set in software, and any socket can feed any of the 64 input channels or insert returns.
The outputs are balanced at +4 dBu and relay protected, so the amps downstream do not get a thump at power on or off.
SLink1 on the panel
SLink is the built-in expansion port, up to 128 x 128 channels. Plug in a GX4816, DX32, DX168, DX164-W, DX012, AR2412, AR84 or AB168 expander, or a DX Hub, and it sets itself up. It can also link to an SQ, Avantis or dLive mixer, or to another AHM-64.
The Lnk/Err LED flashes yellow when the link is up and turns red on a communication error. Use CAT5e or better, up to 100 m.
GPIO2 on the panel
One 10-pin Phoenix plug covers the GPIO: 2 relay outputs and a +10V DC supply on the Out side, and 2 inputs that switch to ground on the In side. Use them for a fire alarm mute, a paging button or a room combine switch.
Output 1 can be wired normally closed or normally open, output 2 is normally open. The +10V supply can deliver 200 mA in total. For more, use an external supply up to +24V DC, with up to 400 mA through any output.
Network (control)1 on the panel
Gigabit RJ45 port for control. Connect a laptop, switch or wireless router to reach AHM System Manager, the IP1, IP6 and IP8 remote controllers, the GPIO interface, the Custom Control app or a TCP control system.
A recessed switch next to it resets the network settings: power off, press and hold the switch, power on and keep holding for at least 20 seconds.
AC mains in1 on the panel
IEC inlet for the internal universal supply, 100 to 240V AC at 50/60 Hz, up to 70 W. A plastic P-clip next to it holds the cord in place (refit it with a T20 Torx driver).
DC In (backup power)1 on the panel
12V DC input on a 2-pin Phoenix plug for a backup supply. Connect it together with the mains: the internal supply runs the unit and the DC input takes over if the mains fails. Use a supply rated 5 A minimum, 8 A maximum.
The drawing uses a round DC socket symbol; the real connector is a 2-pin Phoenix plug.
The plugs come in the box. You get one 10-pin, twenty-four 3-pin and one 2-pin Phoenix plug with strain relief, so you only need balanced audio cable and a small flat screwdriver.
The I/O Port slot
The blank plate in the middle of the rear panel is the I/O Port. Fit an option card there for up to 128 x 128 channels of audio networking, expansion or system integration.
Dante. Use the M-SQ-DANT64 (SQ Dante V2) card for 64 x 64 Dante at 96 kHz. The original M-SQ-DANTE card is not supported. DT168 and DT164-W Dante expanders need this card for preamp control.
What is on the front
- PSU: the internal mains supply is working.
- DC In: a valid 12V supply is connected to the DC input.
- Ready: the unit is powered up and ready to pass audio.
- Sync: audio is locked to a valid clock.
- Sig: a meter that shows the highest level across all inputs and outputs, with peaks flashing red. Its colour and brightness can be changed.
- Fans behind the grilles change speed with temperature. Keep the vents clear.
Rack mounting and cooling
The AHM-64 is 19 in. wide, 2U high and 364 mm (14.3 in.) deep. Remove the plastic feet before you rack it and keep them for later. For free standing use, keep the feet on and stand it on a firm flat surface.
- Leave air space in front of and behind the unit.
- Do not mount it directly above or below gear that runs hot, such as power amplifiers.
- In a tight or warm rack, add a rack fan tray.
- An optional rear rack kit supports the back of the unit in racks 485 to 600 mm deep, for touring or high-vibration installs.
Optional processing module
A slot under the top panel takes an optional module, which adds AEC (acoustic echo cancelling) for conference rooms. A qualified technician should fit it, following the instructions that come with the module.
First connection
- Wire your inputs and outputs to the Phoenix plugs and push them into the rear sockets.
- Connect the Network port to your laptop or control switch with a CAT5e (or better) cable up to 100 m.
- Set your laptop to a static IP address on the same range, for example 192.168.1.10. The processor ships at 192.168.1.90.
- Open AHM System Manager to set up inputs, zones, controllers and presets.
- For apps on a phone or tablet, set your Wi-Fi router to 192.168.1.254 with a DHCP range such as 192.168.1.100 to 192.168.1.200.
Remote access. For System Manager or Custom Control over the internet, use a VPN. If you must forward a port, the processor uses TCP 51321. Third party control uses TCP 51325 (or 51327 with TLS).
Processing at a glance
- 64 x 64 processing matrix with 64 configurable zones (mono or stereo).
- 8 automatic mic mixers, ambient noise compensation and priority ducking. AEC with the optional module.
- 8-band PEQ, dynamics and delay on every input and zone.
- Speaker processing with crossover filter, delay, limiter and PEQ.
- Event scheduler, 32 user profiles and built-in stereo or dual mono playback.
- Up to 268 system inputs and outputs and up to 96 IP remote controllers.
Frequently asked questions
What connectors does the AHM-64 use for audio?+
3-pin Phoenix (Euroblock) connectors: 12 mic/line inputs and 12 line outputs. The plugs come in the box.
What is the SLink port on the AHM-64 for?+
It connects Allen & Heath expanders such as the DX168, DX32, GX4816 and AR2412, a DX Hub, an SQ, Avantis or dLive mixer, or another AHM-64, with up to 128 x 128 channels.
Does the AHM-64 support Dante?+
Yes, with the M-SQ-DANT64 (SQ Dante V2) card in the I/O Port. The original M-SQ-DANTE card is not supported.
What is the default IP address of the AHM-64?+
192.168.1.90 with subnet mask 255.255.255.0 and gateway 192.168.1.254.
Can the AHM-64 run on backup power?+
Yes. Connect a 12V DC supply (5 A minimum) to the DC In along with the mains. It takes over if the mains fails.
How do I reset the AHM-64 network settings?+
Power off, press and hold the recessed reset switch next to the Network port, power on and keep holding for at least 20 seconds.
Plan this audio dsp in your rack
The AHM-64 is in the Allen & Heath library for DaMatrix, with every port mapped so you can drag it into a rack, patch it and print the documentation.
Related Allen & Heath devices
Summarized from the Allen & Heath AHM-64 Getting Started Guide (AP11781 Issue 5). This page is a quick reference; check the full manual for safety warnings and model-specific limits.