Description
The DS-HA1A is a compact Format-A stereo headphone amplifier designed to receive stereo audio and 24 Vdc power over a single twisted-pair RJ45 connection. It provides a 3.5 mm mini-jack headphone output and a user-accessible level control for immediate adjustment. The unit is built with an all-steel Decora style panel and a rear enclosure for discrete wall or cabinet mounting.
Key features include high common mode rejection on the input, a low-noise stereo headphone amplifier, and RJ45 loop-thru capability to daisy-chain additional Format-A receivers. The front panel offers a single-turn volume control and an unobtrusive headphone jack with no illuminated indicators to prevent disturbance in dark environments. The amplifier delivers 25 mW per channel into 100 ohms while maintaining very low distortion.
Performance specifications include a frequency response of 10 Hz to 40 kHz (±1 dB into 100 ohms), THD+N less than 0.01% at 1 kHz (10 mW), noise below -90 dB at maximum gain, and excellent crosstalk performance. The DS-HA1A requires 24 Vdc at 30 mA provided over the Format-A twisted pair link. These metrics ensure clear, low-distortion headphone audio suitable for critical listening in installed environments.
Connectivity is provided through two rear-panel RJ45 jacks that accept RDL Format-A signals and power. Either RJ45 jack can be used as the input while the other serves as a loop-thru output to connect another receiver or module. The left and right audio channels are received on Format-A pairs B and C and are routed to the stereo mini-jack output.
Typical applications include bedside and restroom listening stations in hospitality installations, discrete listening points in multi-room audio systems, and compact installations where shielded cable routing is impractical. The unit’s compact Decora footprint and steel construction make it suitable for wall-mount or cabinet installations where reliability and appearance matter. The lack of front-panel illumination reduces distraction in guest-room settings.
Installation is straightforward using standard twisted-pair cabling and a compatible Format-A sender to provide both audio and power. The DS-HA1A includes an automatically resetting fuse to protect the power input and supports loop-thru configurations for economical multi-point deployment. The product combines simple installation, robust construction, and reliable audio performance to meet common installed-audio requirements.