Atlas Sound AA50PHD – 4-Input 50W BGM Mixer Amplifier with PHD

Product Overview

The Atlas Sound AA50PHD is a 4-input 50-watt mixer amplifier designed for distributed background music, paging, and music-on-hold applications in commercial environments. As a 50W BGM mixer amplifier with 70V output and Push Here Diagnostic (PHD) system testing, the AA50PHD addresses a common installation challenge: verifying that a distributed speaker system is correctly wired and loaded before commissioning. The PHD function checks speaker line wiring, tap settings, and impedance in seconds, reducing troubleshooting time and callbacks on completed installations.

Product Description

The AA50PHD delivers 50 watts into 25V, 70.7V, or 4-ohm loudspeaker systems, covering the full range of commercial distributed audio topologies. Inputs include one microphone/line input (with optional 24VDC phantom power for condenser microphones), two stereo RCA line inputs, and one 3.5mm auxiliary input, accommodating paging microphones, media players, digital music receivers, and mobile devices simultaneously. A rear-mounted DIP switch enables zone muting — allowing Input 1 (typically paging) to automatically mute Inputs 2, 3, and 4 during a page — a standard requirement for business paging systems. A second zone output is configurable from any input via the same DIP switch, providing basic two-zone coverage from a single amplifier. The Remote Input Selection and Remote Level Control feature works with the AtlasIED WPD-RISRL wall plate, allowing users to change input sources and volume from up to 200 feet from the amplifier — useful in restaurants, retail spaces, and conference rooms where the equipment rack is in a remote closet. The PHD diagnostic function checks that total tap wattage does not exceed amplifier rated power, that no speakers are mistakenly set to 8-ohm direct, and that speaker wiring is free from shorts — all critical verification steps that standard mixer amplifiers require manual measurement to confirm. Frequency response is 80Hz–15kHz (±3dB), appropriate for background music and voice paging. Bass and treble EQ controls (±6dB at 100Hz and 10kHz) allow basic tonal adjustment without external processing. The tabletop form factor makes the AA50PHD suitable for counter or shelf installation in locations where rack mounting is not practical.

Key Features

• Push Here Diagnostic (PHD) — Patent-pending automatic system test verifies speaker tap wattage, 8-ohm wiring errors, and line shorts with a single button press.
• 50W Output into 25V / 70.7V / 4 Ohms — Covers the standard distributed audio impedance and voltage configurations used in commercial installations.
• 4 Inputs (Mic/Line, 2 x Stereo RCA, 3.5mm Aux) — Accommodates microphones, media players, streaming devices, and mobile sources without external mixing.
• 24VDC Phantom Power on Input 1 — Enables direct connection of condenser paging microphones without a separate power supply.
• Automatic Input Priority Muting — DIP switch configures Input 1 paging to automatically mute music inputs during a page.
• Zone 2 Output via DIP Switch — Creates a second independent zone output sourced from any of the four inputs.
• Remote Input Selection and Level Control — Compatible with AtlasIED WPD-RISRL wall plate for remote source and volume control up to 200 feet from the amplifier.
• Bass and Treble EQ Controls — ±6dB adjustment at 100Hz and 10kHz provides basic tonal shaping for different acoustic environments.
• RCA Preamp Output — Allows connection to an external amplifier or zone expansion without additional splitting hardware.
• Tabletop Form Factor — Suitable for shelf, counter, or millwork installation where rack mounting is not practical.

Typical Applications

• Conference room
• Boardroom
• Commercial meeting space
• House of worship
• Multi-purpose room
• Training room

Technical Specifications

Frequently Asked Questions

Q: What does the PHD (Push Here Diagnostic) function test?

A: The PHD checks three conditions: (1) that the total tap wattage of connected speakers does not exceed the amplifier’s 50W rating; (2) that no speakers are accidentally wired at 8-ohm direct rather than at a 70V tap; and (3) that speaker wiring is free from shorts. This replaces the need for manual impedance measurements with a one-button verification test.

Q: Can the AA50PHD be used for paging with automatic music muting?

A: Yes. A rear-mounted DIP switch configures the unit so that Input 1 (the mic/line paging input) automatically mutes Inputs 2, 3, and 4 when a paging signal is detected.

Q: How does the Remote Input Selection feature work?

A: The AA50PHD supports the AtlasIED WPD-RISRL wall plate, which connects to the amplifier’s remote control port and allows a user to select the input source and adjust volume from up to 200 feet away — useful when the amplifier is installed in a remote equipment closet.

Q: Is the AA50PHD compatible with condenser microphones requiring phantom power?

A: Yes. Input 1 supports optional 24VDC phantom power for condenser microphones.

Q: What output voltages does the AA50PHD support?

A: The AA50PHD supports 25V, 70.7V, and 4-ohm direct speaker loads, covering the standard configurations used in commercial distributed audio installations.