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Pro-Ject Tube Box S2 Tube Phono Preamplifier (Open Box)

Pro-Ject Tube Box S2 Tube Phono Preamplifier (Open Box)

Regular price $375.00 USD
Regular price $499.00 USD Sale price $375.00 USD
Sale Sold out

Tube Box S2 — Premium Tube Phono Preamplifier

This is an open box Item. Very little use as a demo, like new. Includes original packaging and accessories. 

The Tube Box S2 combines the warmth and musicality of vacuum tube technology with exceptional versatility and precision. Featuring dual ECC83 (12AX7A) tubes in a true dual-mono configuration, this premium phono stage delivers the rich, three-dimensional sound that only tubes can provide. With comprehensive adjustability for both MM and MC cartridges, the Tube Box S2 adapts perfectly to your analog setup while maintaining reference-quality RIAA accuracy.

🔥 Dual-Mono Tube Design

Features two dual-triode ECC83 (12AX7A) vacuum tubes in a true dual-mono configuration for optimal channel separation. Each channel has its own dedicated tube section, ensuring the left and right channels remain completely independent from input to output.

Experience the legendary warmth, depth, and three-dimensionality that only vacuum tube amplification can deliver.

🎚️ Universal Cartridge Compatibility

Compatible with both moving magnet (MM) and moving coil (MC) phono cartridges. Front-panel gain selector offers six settings (40, 43, 50, 53, 60, or 63dB) to perfectly match your cartridge's output level, from high-output MM to low-output MC designs.

One preamp that works flawlessly with virtually any cartridge on the market.

⚙️ Comprehensive Loading Adjustability

DIP switches on the bottom panel allow precise adjustment of input impedance (10, 100, 470, 1k, 2k ohms, plus fixed 47kΩ) and capacitance (47, 147, 267, 367, 487, 587 pF). This extensive range ensures optimal electrical matching for any cartridge.

Fine-tune the loading to extract maximum performance from your specific cartridge.

🌊 Subsonic Filter

Built-in subsonic filter with -18dB/octave slope at 20Hz effectively reduces low-frequency rumble from turntable motors and footfalls. This protects your speakers and amplifier from wasted power on inaudible frequencies while maintaining full bass response.

Cleaner sound and reduced stress on your amplification chain.

🎯 Audiophile-Grade Components

Premium polypropylene capacitors throughout the signal path ensure transparent, uncolored sound reproduction. These high-quality components are specifically chosen for their sonic neutrality and long-term stability.

No-compromise parts quality for reference-level performance.

🛡️ Advanced Shielding

Sophisticated aluminum/metal sandwich chassis construction provides exceptional shielding from both vibration and electromagnetic interference. The multi-layer design dissipates resonances while blocking external noise sources.

Professional-grade construction ensures pristine signal integrity in any environment.

🔌 Premium Connectivity

Gold-plated RCA stereo input and output pairs ensure solid, corrosion-free connections for years of reliable service. Gold plating provides superior conductivity and long-term oxidation resistance.

Professional-quality connections you can trust for the long haul.

🔬 Precision RIAA Equalization

Exceptional RIAA response accuracy of ±0.4dB (20-20,000 Hz) ensures faithful reproduction of the original recording. This precision equalization curve perfectly reverses the RIAA encoding applied during vinyl mastering.

Hear your records exactly as the artist and mastering engineer intended.

📐 Technical Specifications

Cartridge Type:
MM & MC
Tube Complement:
2× ECC83 (12AX7A) dual-triode
Gain Settings:
40, 43, 50, 53, 60, 63dB
Impedance Settings:
10, 100, 470, 1k, 2k Ω, 47kΩ
Capacitance Settings:
47, 147, 267, 367, 487, 587 pF
Signal-to-Noise Ratio:
80dB (MM & MC)
THD:
<0.05%
RIAA Accuracy:
±0.4dB (20-20,000 Hz)
Subsonic Filter:
Yes (-18dB/octave @ 20Hz)
Cartridge Loading:
Selectable via DIP switches
RCA Inputs:
1 Pair (Gold-Plated)
RCA Outputs:
1 Pair (Gold-Plated)
XLR Connections:
Not Available
Digital Outputs:
None
Capacitors:
Audiophile-grade polypropylene
Chassis:
Aluminum/metal sandwich
Dimensions:
4.06" W × 3" H × 5.25" D
Weight:
14.4 oz
Circuit Design:
Dual-mono tube topology
Adjustable Resistance:
Yes
Adjustable Capacitance:
Yes

🎵 Perfect for: Audiophile turntable systems • MM and MC cartridges • Tube sound enthusiasts • High-fidelity vinyl playback • Versatile analog setups • Reference-quality sound • Dedicated listening rooms • Cartridge matching flexibility

"The warmth of tubes meets the precision of modern engineering."

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