Format-A Stereo Headphone Amplifier (Compatible with Guest Room Audio System)

The RDL D-HA1A is a compact stereo headphone amplifier designed for RDL TP Format-A installations and compatible guest room audio systems. It combines a standard mini-jack headphone output with user level control in a wall- or cabinet-mountable Decora-design assembly. Signal and 24 Vdc power arrive through an RJ45 connection from a Format-A sender, while a second RJ45 connection provides loop-through capability for additional modules.

Ideal Use Cases

This model is suited to guest room audio systems that need a convenient, locally controlled headphone connection. Its wall and cabinet mounting options also make it appropriate wherever a fixed Format-A headphone listening point is required. The user level control lets the listener adjust the headphone output at the installed location. Because the amplifier receives its audio signal and power from an RDL twisted-pair Format-A sender, it integrates directly into systems built around that distribution format.

Why Choose This Model

The D-HA1A places the essential headphone controls and connection at the point of use. Its stereo output delivers 25 mW per channel into 100 ohms, and the standard mini-jack accommodates the headphone connection. The RJ45 loop-through is especially useful when the system design calls for additional compatible modules beyond the headphone amplifier. An automatically resetting fuse provides integrated protection, while the all-steel panel and rear enclosure form a self-contained installation assembly. White, black, and stainless-steel versions are available to suit different installation finishes.

Installation and Integration

The amplifier can be mounted in a wall or cabinet and uses a Decora-design front panel. Its input connection is RJ45, carrying the RDL TP Format-A signal from a compatible sender over twisted-pair cable. The module uses Format-A signal pairs B and C. Power is also supplied through RJ45 by the Format-A sender, with a requirement of 24 Vdc at 30 mA. This shared signal-and-power connection keeps the required interface concentrated at the rear of the module. The Format-A output is an RJ45 loop-through connection for extending the installation to additional modules. The unit measures 1.55 inches deep, 1.72 inches wide, and 4.11 inches high.

Performance Highlights

The D-HA1A has a specified frequency response of 10 Hz to 40 kHz, within plus or minus 1 dB when operating into 100 ohms. THD+N is less than 0.01 percent at 1 kHz and 10 mW. Noise is specified at less than -90 dB at maximum gain. Crosstalk is less than -85 dB at 1 kHz and less than -70 dB from 20 Hz to 20 kHz. Together with its 25 mW-per-channel stereo output rating into 100 ohms, these published figures define the amplifier’s electrical performance for compatible headphone loads and Format-A sources.

What Makes It Different

This model combines a user-accessible headphone amplifier, Format-A connectivity, sender-supplied power, and module loop-through in a single mounting assembly. Unlike a freestanding headphone amplifier, the D-HA1A is specifically arranged for installation in a wall or cabinet. Its RJ45 connections serve the RDL TP Format-A signal path, power input, and downstream loop-through rather than Ethernet networking. The use of two Format-A signal pairs, B and C, and the ability to connect additional modules make its role within an RDL twisted-pair system clearly defined.

Final Assessment

The RDL D-HA1A is a focused solution for adding user-controlled stereo headphone listening to an RDL TP Format-A installation or compatible guest room audio system. Its standard mini-jack output, 25 mW-per-channel rating, RJ45 signal and power connection, loop-through output, resetting fuse, and wall- or cabinet-mount design provide the core functions needed at a fixed listening location. Three available finishes support coordination with the surrounding installation.