Pro-Ject Phono Box RS2 Phono Stage

Fully Balanced · Fully Discrete · Op-Amp Free · Reference-Grade Adjustable Phono Stage

The Pro-Ject Phono Box RS2 is the brand's reference-grade phono preamplifier from the RS series, featuring a fully balanced, true dual-mono, and fully discrete (op-amp free) circuit design, with passive RIAA and DECCA equalization. Its standout features include continuously adjustable MC impedance loading during playback and channel balance control, allowing it to perfectly match almost any MM or MC cartridge.

High-end balanced inputs/outputs and ultra-low distortion design make it an ideal choice for those seeking the ultimate vinyl performance.

Product Information

• Type: Fully Balanced MM / MC Phono Preamplifier
• Circuit Design: Fully discrete (op-amp free), true dual-mono
• Equalization Curves: Selectable passive RIAA and DECCA
• Inputs / Outputs: Balanced XLR + unbalanced RCA (simultaneous connection and switching possible)
• Color: Black or silver
• Origin: Hand-made in Europe
• Accessories: External 20V DC power supply

Core Technology Highlights

• Fully Balanced True Dual-Mono Design: Excellent channel separation and anti-interference capability
• Fully Discrete Circuitry: No op-amps used at all, resulting in a more natural and pure sound
• Passive RIAA / DECCA Equalization: Accurately reproduces the characteristics of different records
• Continuously Adjustable MC Impedance: 10–1000Ω potentiometer adjustment, allowing real-time fine-tuning during playback
• Channel Balance Control: Corrects minor differences between left and right channels of the cartridge
• High Gain Range: MM 40–50dB; MC 60–70dB (+6dB for XLR output)
• Adjustable Capacitance: MM 50–400pF, eight-step adjustment
• Subsonic Filter: 20Hz / 18dB/octave, switchable
• Metal Chassis: Effectively shields against vibration and electromagnetic interference
• True Balanced Support: Fully leverages the advantages of a balanced system

Detailed Specifications

• Input Impedance: MM fixed 47kΩ; MC continuously adjustable 10–1000Ω
• Input Capacitance: 50 / 100 / 150 / 200 / 250 / 300 / 350 / 400 pF
• Gain (RCA): MM 40 / 43 / 46 / 50 dB; MC 60 / 63 / 66 / 70 dB (XLR +6dB)
• Signal-to-Noise Ratio: MM approx. 89dB (A-weighted); MC approx. 76–79dB (A-weighted)
• Total Harmonic Distortion: MM <0.0015%; MC <0.0024%
• RIAA Accuracy: 20Hz–20kHz / max. ±0.4dB
• Subsonic Filter: 20Hz / 18dB/octave
• Inputs / Outputs: 1 set RCA + 1 set XLR each
• Power Supply: External 20V / 3A DC
• Power Consumption: Max. approx. 350mA (standby <1W)
• Dimensions: 206 × 72 × 200 mm (approx. 230mm including terminals)
• Weight: Approx. 1.6 kg

Sound Quality and Performance

The Phono Box RS2 delivers an extremely clean, precise, and dynamic sound. The background is exceptionally black, details are rich, and the soundstage is expansive with clear layering. Mid-frequencies are natural and full-bodied, bass is powerful with excellent control, and treble is clear without being harsh. Overall, it presents a neutral-to-mature sound, balancing musicality with analytical detail.

Its fully balanced design and adjustable loading allow it to fully exploit the potential of high-end MC cartridges, making it a highly capable phono stage for reference-grade systems.

Online Reviews

• Stereophile: Excellent fully balanced and highly adjustable features, clean sound, rich details, truly high-end performance.
• ecoustics: "Can compete with much more expensive units... brings true presence and musical integrity to vinyl."
• Users and Media: Continuously adjustable impedance and channel balance control are extremely practical; rare value for money and functionality at its price point, highly recommended.