The HPA-4 from Nady is a high-quality stereo headphone amplifier that provides 4 independent channels in a compact and rugged 1RU rackmount chassis. Each channel features 1/4" phone and line stereo outputs, as well as servo-balanced L/R 1/4" inputs. Selector switches let you choose to send any input to any output. This creates terrific versatility, allowing all 4 headphone outputs to monitor the same input signal, or each monitor its own unique input.
Each channel has its own volume control, letting users pick the level that's best for them. Thanks to the versatile outputs, up to 4 units can be daisy-chained together for additional headphone and line distribution setups. The amplifier features high-quality components with a no-compromise circuit design to provide reference-quality audio and excellent headroom, even at high volume levels. The shielded internal power supply has a selectable voltage for convenient international use.
| Number of Channels | 4 |
| Input Connections |
4 x 1/4" Servo-Balanced Inputs (L/R) 1 x AC Power Input |
| Output Connectors |
4 x 1/4" Stereo Headphone Jacks 4 x 1/4" Stereo Line Outputs |
| Maximum Output Level | 300mW @ 32 Ohms |
| Function Controls |
1 x Power Switch 4 x Volume Knobs 4 x Input Select Switches 1 x Voltage Select Switch |
| Frequency Response | 20Hz - 20kHz |
| THD + N | 0.02% |
| Signal to Noise Ratio | > 80dB |
| Display | No |
| Power Requirements | 100-240VAC, 50/60Hz, Selectable |
| Power Consumption | 11.5VA |
| Fuse |
100-120VAC: 630mA (Slow-Blow) 200-240VAC: 315mA (Slow-Blow) 100-240VAC: 500mA (Slow-Blow) 5x20mm Glass Type |
| Dimensions (HxWxD) | 1.75 x 19 x 8.5" (44 x 483 x 217mm) |
| Weight | 6.93 lbs (3.15kg) |