Pro-Ject Amp Box Mono RS Mono Amplifier w/Tube Buffer

"Amazingly Powerful"

Go monoblock, and go small at the same time. Pro-Ject's highly efficient, powerful, affordable, and compact Amp Box Mono RS gives you the sonic benefits of a single-channel power amp for your application, from home theater to sophisticated two-channel systems.

In its May 2014 issue, Germany's Stereoplay magazine gave the Amp Box Mono RS a "Top Class" rating for sound quality and an overall rating of "Very Good." According to the review, "In view of its extremely compact dimensions, this mono amplifier is amazingly powerful with high efficiency Class-D technology. It sounds highly powerful and crisply strong."

The Amp Box RS Mono offers three-dimensional sound-staging, perfect micro dynamics, and ultimate resolution combined with high power output and 2 ohm capability. It is the perfect solution for bi-amping or tri-amping applications. Amp Box RS Mono is the perfect companion for Pre Box RS and will deliver the pristine sonic experience that audiophiles crave.

Highly Efficient, Powerful Design

The Amp Box RS Mono boasts a fully balanced mono design for stellar sound quality. It features both XLR balanced and RCA unbalanced inputs.

Highly efficient, energy saving PWM (Pulse Wave Modulation) modules pack a huge amount of performance into minimal circuitry. The circuit design takes maximum advantage of SMD (Surface Mount Design) construction for the shortest possible signal paths. The power supply provides highly efficient conversion from mains to output power (92%).

Powerful, Drives a Wide Range of Speakers

Delivering a big 195 watts into 4 ohms and 125 watts into 8 ohms, the Amp Box RS Mono delivers impressive amounts of power, and it remains stable into even a 2 ohm load! That gives you lots of flexibility with speaker choices.

Vacuum Tube Input Buffer

This is no ordinary compact mono amp. The Amp Box Mono RS has a tube buffer input stage using an ECC88 (6922) vacuum tube. Why the tube stage in this age of digital amplification architecture? Because nothing else on earth but a vacuum tube circuit can deliver the lush, warm, rich sound from the Golden Age of hi-fi when vacuum tube gear ruled the earth.

Because of its high power and heat emission, the Amp Box RS Mono's luxurious aluminum casing, which is available in silver or black, should not be combined with the optional Design Box Acrylic case system (available separately).

The Perfect Partner for Pro-ject's Pre Box RS

The Amp Box RS Mono is the perfect partner for Pro-Ject's Pre Box RS line stage preamplifier. The two were made to go together, and are beautifully matched from circuitry to cosmetics.

• Compact monoblock power amplifier
• Hybrid solid state and vacuum tube design
• Fully balanced design (Pulse Wave Modulation)
• Highly efficient conversion from mains to output power (92%)
• 2 ohms drive capability
• Tube buffer stage with reference quality sound
• SMD construction for shortest signal paths
• Balanced XLR and unbalanced RCA inputs
• Top-quality speaker terminal
• Metal casing protects against vibration and interference
• DC power supply (< 1 watt standby power)
• Available in silver or black

• Tube assembly: 1 x ECC88 (6922)
• Power output: 125W @ 8 ohms; 195W @ 4 ohms; 2 ohms drive capability
• Frequency response: 10Hz - 50kHz (+ 0dB, - 3dB)
• Signal to noise ratio: >-100dB (IEC -A)
• THD: < 0.05% @ 100W
• Input sensitivity: 1.35V
• Input Impedance: 22 kohms
• Speaker terminal: 4mm banana, spade or bare wire
• External power supply: 48V/2,5A DC;100 - 240V, 50/60Hz
• Standby consumption: < 1watt
• Dimensions: 8.1" wide, 2.8" high, and 7.8" deep (8.6" deep with connections)
• Weight: 4.45 lb without power supply

"Sound: Top Class"
"Verdict: Very Good"

"In view of its extremely compact dimensions, this mono amplifier is amazingly powerful with high efficiency Class-D technology. It sounds highly powerful and crisply strong."

- Germany's Stereoplay magazine, May 2014