Pro-Ject Head Box RS Headphone Amplifier

Head Box RS

High-end headphone amplifier

Ultimate high-end headphone sound!

Head Box RS is a reference class headphone amplifier with fully balanced tube input stage (double triode 6922) and unbalanced Class A "FET (Field Effect Transistor)" output stage. It has a balanced and an unbalanced input with looped-through outputs for use with other components.

The volume control consists of a high-precision control for highest channel equality of the left and right channel.

A special impedance selector switch allows the output impedance to be set in 3 steps (5, 20 and 50 ohms) for the best possible match between amplifier and headphones. Pro-Ject recommends listening tests with different switch positions to determine the best sound experience for your headphones.

A sophisticated multi-stage power supply with four different output voltages guarantees the best possible noise ratios and the most accurate reproduction of details, dynamics and soundstage with any dynamic headphone!

Features & Benefits

• Fully symmetrical double mono construction
• tube input stage
• Class-A FET Output stage
• Selectable output impedance for optimum reproduction
• Superior small distortions
• Extremely low-noise for maximum dynamics & attention to detail
• 6,3mm jack connection
• Full metal housing in silver or black
• Optional upgrade option: Linear power supply Power Box RS Uni 1 (or 4) for even better sound quality

Technical data

• output power: 350mW at 32 Ohm / 60mW at 300 Ohm
• Crosstalk - 58 dB
• Frequency response: 30 Hz - 20 kHz /(+0.2 dB; -0.05 dB)
• Distortion factor (IMD: 0.17% (XLR in, output impedance 5 Ohm, load resistance 32 Ohm)
• Gain: 9 dB
• Signal-to-noise ratio: 99 dBA at full modulation
• Headphone socket: 3-pin jack socket 6.3 mm
• High level inputs: 1 pair RCA/Cinch jacks each & 1 pair XLR jacks each
• High level outputs: 1 pair each of RCA/cinch jacks & 1 pair each of XLR jacks
• Mains connection: plug-in power supply, 20 V/3 A DC; 220 - 240 V, 50 Hz
• Current consumption: 1.3 A DC
• Dimensions W x H x D: 206 x 72 x 200 (209) mm
• Weight: 2150 g without power supply unit