| ATX Specification | ARXSpecification | |||
| Input level | 2.5mV to 775 mV | Audio output power | 200mW nominal | |
| Input impedance | 600 W 47K Ohms (switched). | Output connector | Screw type socket | |
| Output level | 0 to 2.5 V RMS or 200 mW (phones) | Output level | Adjustable, microphone or line level | |
| Output impedance | 600 W, 3 kW, 47 kWor 8W (phones) | Output impedance | 600 ohms or 8 ohms | |
| Light source wavelength | 850nm | Optical input range | 1µW - 174µW | |
| Peak optical power output | >20µW | Light detector | Pin diode | |
| Power requirement | +12v to +18v at 100mA | Overall size | 125x63x30mm | |
| Overall size | 125x63x30mm | Power requirement | +11v to+15v @100mA | |
| Mains power cube | MPC407 (3 pin UK) | Mains power cube | MPC407 (3 pin UK) | |
| MPC409 (2 pin Euro) | MPC409 (2 pin Euro) |