Australian Monitor AMIS ZRM4 6x4 Routing Mixer

Introduction

The AMIS ZRM4 is a 1 RU zone routing mixer featuring 6 inputs (balanced XLR mic/line or dual RCA/balanced XLR line) connectable to any of 4 zone outputs. Input #1 offers priority paging functionality, individually selectable per zone output. Front panel switches and bi-colour status LEDs simplify routing. Each input includes a 2-stage EQ and an internal gain trim (+/- 15dB). Phantom power and high-pass filters are also available per input. Balanced XLR zone outputs feature status LEDs and switchable paging mic priority. Remote VCA volume control is supported. Onboard Alert, Evacuation, Bell, and Pre Announce tones are included. The AMIS ZRM4 provides a compact and versatile solution for multizone signal routing.

Contents

• Introduction
• Front Panel
• Rear Panel
• Internal Adjustments
• Basic Setup and Operation
• Advanced Features
• Block Diagram
• Specifications

Safety Information

⚠️ CAUTION: RISK OF ELECTRIC SHOCK. DO NOT OPEN. NO USER-SERVICEABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED SERVICE PERSONNEL.

This symbol indicates the presence of uninsulated "dangerous voltage" within the product's enclosure that may constitute a risk of electric shock.

❗ WARNING: TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK. DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE.

⚠️ Caution: This symbol indicates important operation and maintenance instructions.

To prevent electric shock, do not use a polarized plug with an extension cord or outlet unless the blades can be fully inserted to prevent exposure. Match the wide blade of the plug to the wide slot and insert fully.

Front Panel

The front panel provides controls for input and output management.

Input Control Section

• 1. Output Assignment Switches: Four switches per input channel allow assignment to any of the four outputs. A yellow LED indicates an active assignment. Multiple switches can be pressed for mixed inputs to an output.
• 2. Tone Controls: Each input has a two-stage shelf EQ (Bass and Treble).
• 3. Level Control: Adjusts the input signal level.
• 4. Input Status LEDs: Bi-colour LEDs indicate signal presence (green) or clipping proximity (red, 6dB before clip) and clipping (solid red, 3dB before clip). These are post-level control.

Output Control Section

• 5. Output Level Controls: Four potentiometers control the level of each output.
• 6. Priority Override Enable Switches: When active, allow Input Channel #1 to have priority over other inputs for the selected output.
• 7. Output Status LEDs: Indicate signal presence (green) or signal peak above 0dBu (red).

Rear Panel

The rear panel houses all input and output connections, as well as power and control interfaces.

• 1. Channel Inputs: Each channel features a dual RCA (line level, mono summed) and an XLR (balanced mic/line) input. XLR inputs support selectable +15V phantom power and have adjustable sensitivity (MIC/LINE). Channel #1 is designated as the priority input.
• 2. Outputs: Balanced XLR outputs for each of the four zones.
• 3. Chime Module Control Connections: Terminals (ALERT, EVAC, BELL, PRE) for triggering onboard tones by shorting to COM. EVAC/ALERT mute all inputs except Channel #1. BELL/PRE-ANNOUNCE route with Channel #1.
• 4. VCA: Connectors for remote wall panels (RC1) or 500k ohm log potentiometers to control output levels remotely. This control is before the master output level.
• 5. Power 20V AC: 2.1mm connector for the supplied 20V AC adapter. Can also accept 24-34V regulated DC.
• 6. Earth: Earth stud for connecting a mains earth strap.

Note on Grounding: Grounding the chassis via the earth stud or equipment rack may be necessary to eliminate system noise.

Internal Adjustments

Internal switches and controls allow for fine-tuning of input signals.

• 1. HPF (High Pass Filter): Switchable filter (approx. 150Hz knee) to reduce low-frequency rumble, useful for microphones.
• 2. Phantom: Provides +15V phantom power for condenser/electret microphones on the XLR input.
• 3. MIC / LINE: Switches control the sensitivity of the XLR input for microphone or line-level signals. Both switches must be in the same position.
• 4. Gain Trim: Boosts or cuts input gain by up to +/- 15dB, affecting both XLR and RCA inputs for optimal gain structure. Centre position is 0dB.
• 5. Tones Level: Controls the overall volume of the onboard generated tones.

Basic Setup and Operation

The AMIS ZRM4 accommodates various sources (microphones, DVD/CD players) and drives power amplifiers or other mixers. Proper gain structure is crucial for optimal results.

Initial Settings:

• Program Input Gain Controls: Half (12 o'clock)
• XLR Mic/Line switch: MIC
• Input Level Controls: Off
• Output Level Controls: Off

Connecting Sources:

• Connect sources to appropriate input connectors.
• Set MIC/LINE switches to "MIC" for microphones.
• Set phantom switch to "PHANTOM ON" for condenser/electret mics.
• Set HPF switch to "HPF ON" for speech microphones (paging).
• Connect paging/priority sources to Channel #1.

Connecting Outputs:

• Turn amplifiers OFF. Connect AMIS ZRM4 outputs to amplifier line-level inputs.
• Turn AMIS ZRM4 ON, then turn amplifiers ON. Set amplifier level controls to maximum if available.

Testing Input Levels:

• For each source, play the loudest anticipated signal (music or page).
• Input status LED should be green, occasionally red.
• If LED is consistently red (>5% of the time), reduce input gain trim.
• If LED never turns red, increase input gain trim if needed.

Assigning Sources to Outputs:

• Activate output assignment switches to route signals to desired outputs. Yellow LEDs indicate routing.

Setting Up Priority Function:

• For priority signals (e.g., paging mic), engage the "Priority Override Enable" switch for the relevant zone. (See Advanced Features for details).

Setting Levels:

• Set input levels to approximately 5.
• Adjust output levels for each zone to the desired listening volume.
• Balance relative input levels for each zone. Prioritize the setup of the priority signal first.
• Aim for input and output level controls between 3 and 7. Input levels should generally be higher than output levels.

Advanced Features

Tone Controls

Each input channel has Bass (+/- 12dB at 100Hz) and Treble (+/- 10dB at 10kHz) trim pots for tone adjustment. Using bass cut with the HPF can reduce microphone rumble. Note: Excessive bass/treble boost may cause clipping; monitor input status LEDs and adjust gain trim if necessary.

Priority Override

Each output channel can mute other input signals when a signal is present on Channel #1, provided Channel #1 is assigned to that output. This is activated by pressing the "CH1 Priority Enable" switch. Useful for paging or other interruptible audio sources.

Remote Volume Control

Output levels can be controlled remotely via an RC1 panel or a 500k ohm log potentiometer connected to the VCA pins on the rear panel. The remote control acts before the master output level, setting the maximum level. It does not affect Channel #1 or onboard tones, ensuring paging is always audible. If paging is too loud, adjust the master output level control for that zone.

Note: For a 500k ohm pot, connect to the wiper and anti-clockwise terminals for max resistance = max volume.

Tone Module

The tone module provides four prioritized, triggerable tones:

• EVAC: Evacuation signal. Mutes all inputs except Channel #1. Continues until the short is removed.
• ALERT: Alarm signal. Mutes all inputs except Channel #1. Continues until the short is removed.
• BELL: A two-strike chime with a short gap, repeated. Continues until the short is removed.
• PRE-ANNOUNCE: A four-note chime, sounds once per trigger.

Note: BELL and PRE-ANNOUNCE tones route with Channel #1. EVAC and ALERT route to all outputs after level controls to ensure audibility. EVAC and ALERT do not mute Channel #1, so continuous sources (radio, CD player) should not be connected to Channel #1 if these tones are used.

Block Diagram

The block diagram illustrates the signal flow through the AMIS ZRM4. Each of the 6 input channels processes signals through:

• Input Stage: Mic/Line selection, +5dB pad, Gain Trim (+/- 15dB), Phantom Power (for XLR mic input), HPF (High Pass Filter), and EQ (Equalization).
• Signal Routing: Output Assignment Switches route the processed signal to one or more of the four zone outputs (A, B, C, D).
• Output Processing: Each output path includes Mute, VCA control (for remote level adjustment via RC1 or potentiometer), and Priority Override Enable (allowing Channel #1 to take precedence).
• Outputs: Zone A, B, C, and D outputs receive the final mixed and controlled signals, with an additional +6dB gain stage.
• Tone Generator: An external tone trigger input allows activation of the Tone Generator, which produces Bell & Chime, and Evac & Alert signals. These tones are routed to the outputs as described in the Advanced Features section.

RC1 remote level control is available separately.

Specifications

Contact Information

Australia and New Zealand

Australian Monitor
www.australianmonitor.com.au

• Sydney (NSW & ACT SALES): 149 Beaconsfield Street, Silverwater NSW 2128. Phone: (02) 9647 1411. Email: nsw@audiotelex.com.au
• Melbourne (VIC & TAS SALES): 22/277 Middleborough Road, Box Hill VIC 3128. Phone: (03) 9890 7477. Email: vic@audiotelex.com.au
• Brisbane (QLD SALES): 42 Commercial Road, Fortitude Valley QLD 4006. Phone: (07) 3852 1312. Email: qld@audiotelex.com.au
• Adelaide (SA & NT SALES): 31 Walsh Street, Thebarton SA 5031. Phone: (08) 8352 4444. Email: sa@audiotelex.com.au
• Perth (WA SALES): 299 Fitzgerald Street, West Perth WA 6005. Phone: (08) 9228 4222. Email: wa@audiotelex.com.au
• Auckland (NZ SALES): Unit B, 11 Piermark Drive, Albany 1331, New Zealand. Phone: (09) 415 9426. Email: audiotlx@nznet.gen.nz

Europe/Asia/Middle East

International Sales
www.australianmonitor.com.au

149 Beaconsfield Street, Silverwater NSW 2128 Australia. Phone: 61 2 9647 1411. Email: international@audiotelex.com.au

USA/South America

Sennheiser Electronic Corporation
www.australianmonitor.com

1 Enterprise Drive, Old Lyme CT 06371 USA. Phone: 1 860 434 9190. Email: jalexander@sennheiserusa.com