A specially designed output circuit will drive most headphones to maximum levels, regardless of headphone impedance. 600 ohm headsets are driven to levels comparable to those obtained using a 20 watt/channel power amplifier.
The unbalanced inputs have selectable -10 or +4 dB levels. The gain control and headphone jack are mounted independently, providing installation flexibility (side by side, front panel/rear panel, etc.). A complete wiring harness assembly with a stereo gain control is included with the module.
The HM-1 is also available in an under-desk mounting configuration, as the HMS Headphone Module Station.
| Power Requirements | +/-10 VDC to +/-20 VDC, 350 mA (max., 8 ohms) |
|---|---|
| Input Impedance | 10 kohms, unbalanced |
| Input Signal Level | -10 dBV/+4 dBm nominal (via jumper) |
| Headphone Impedance | 8 ohms to 2 kohms |
| Output Level | 100 mW nominal, 500 mW max., 8 ohms to 600 ohms |
| Output Connector | 1/4" TRS |
| Frequency Response | 20 Hz to 30 kHz +/-0.15 dB |
| Total Harmonic Distortion | .03%, 20 Hz to 30 kHz, nominal output |
| Hum and Noise | -80 dBm, 20 Hz to 30 kHz |
| HM-1 | 1.4 W x 1.2 H x 3.7 D |
|---|---|
| HMS | 3.3 W x 1.5 H x 5.0 D |