ASHLY FA 125.4 1/2U Power Amplifier 4 x125W @ 4/8 Ohms, 25/70/100V

Product Overview

The Ashly FA 125.4 is a half-rack (1/2U) 4-channel compact Class D power amplifier delivering 125W per channel at 4 or 8 ohms with full 25V, 70V, and 100V constant-voltage support on all four channels. Engineered for commercial AV installations where space is limited, the FA 125.4 is designed to be concealed under tables, mounted behind displays, or placed inside kiosks and exhibit structures. The Silent Active Cooling System and front panel lockout make it a practical choice for occupied commercial spaces including conference rooms, training rooms, and meeting areas where noise and unauthorized adjustment are concerns.

Product Description

The Ashly FA 125.4 compact half-rack power amplifier provides four channels of 125W output in a form factor that fits in locations where standard amplifiers are too large. Its Class D design operates at high efficiency, and a Silent Active Cooling system keeps fan noise minimal in occupied spaces. The FA 125.4 supports 25V, 70V, and 100V constant-voltage distributed audio alongside standard low-impedance 4 and 8 ohm operation, with the mode switchable per channel to accommodate mixed speaker systems. Dynamic power sharing between channel pairs allows up to 250W total per pair when one channel carries a lighter load, giving the installer flexibility to design uneven zone loads without adding additional amplification. Built-in DSP activates automatically in Hi-Z mode: an 80 Hz high-pass filter protects distributed speakers from bass loading, and a clip limiter prevents transient overload. Front panel controls include per-channel level potentiometers, status LEDs, and a power switch, all of which can be disabled for security. Remote GPIO supports DC level control, standby, and failure status signaling for integration with room automation. Input sensitivity is field-switchable between -10 dBV and +4 dBu. Auto Sleep/Wake mode places the unit in standby after 30 minutes of signal absence to reduce energy consumption and heat generation. A front-panel USB port allows firmware updates in the field. The FA 125.4 carries cTUVus, CE, FCC, and RoHS certifications and is Energy Star compliant.

Key Features

• 4 Channels, Half-Rack Width — Four independent channels of amplification in a 1/2U half-rack enclosure for concealed AV installs.
• 25V / 70V / 100V Constant-Voltage Output — All four channels support 25V, 70V, and 100V distributed audio for commercial paging and BGM applications.
• 125W Per Channel at 4 or 8 Ohms — Rated output with all channels driven simultaneously.
• Dynamic Power Sharing — Channel pairs share a 250W total budget, allowing uneven load distribution within the same amplifier pair.
• Silent Active Cooling — Whisper-quiet fan designed for noise-sensitive occupied spaces including conference rooms and boardrooms.
• Auto Sleep/Wake Mode — Enters low-power standby after 30 minutes of inactivity; resumes instantly upon signal detection.
• Built-in 80 Hz HPF and Clip Limiter — Automatic DSP protection in Hi-Z mode protects smaller distributed speakers.
• Front Panel Security Lockout — Disables level controls and power switch to prevent unauthorized adjustment in accessible installations.
• Remote GPIO — DC level control, standby input, and failure output for room control system integration.
• Switchable Input Sensitivity — -10 dBV or +4 dBu to match consumer and professional source levels.
• USB Firmware Update Port — Field-upgradable firmware via front-panel USB connection.
• Energy Star Compliant — Meets energy efficiency requirements for commercial building installations.

Typical Applications

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

Technical Specifications

Frequently Asked Questions

What constant-voltage standards does the FA 125.4 support?

The FA 125.4 supports 25V, 70V, and 100V constant-voltage operation, all four channels, selectable per channel. This covers the standard distributed audio voltage standards used in North American and international commercial AV installations.

How does the FA 125.4 differ from the FA125.4?

Both are half-rack 4-channel amplifiers with the same core specifications. The FA 125.4 also explicitly includes 25V operation in its specification alongside 70V and 100V, providing the widest constant-voltage compatibility in the FA 125 series.

Can the FA 125.4 be installed without a rack?

Yes. The FA 125.4 is designed for non-rack concealed installs including under-table, wall-mount behind displays, inside kiosks, and exhibit structures. Optional mounting accessories (FATWB table/wall bracket, FA1.2RM rack kit) are available.

Is the FA 125.4 suitable for installations where the amplifier is accessible to end users?

Yes. Front panel level controls and the power switch can be disabled via the lockout feature, preventing unauthorized adjustment in spaces where the amplifier is within reach of non-technical personnel.

Does the FA 125.4 integrate with room control systems?

Yes. The Remote GPIO connection supports DC level control, standby triggering, and failure status output for integration with standard commercial building automation and room control systems.