Phono Box RS2

Fully balanced, fully discrete phono preamp of the highest class

Reference class phono preamplifier with unique impedance control

The Phono Box RS2 is the ultimate phono preamplifier of the highest class. It is fully balanced from the input to the output. Electronics are fully discrete, no op-amps are in use and it uses split passive RIAA and DECCA equalization.

Discrete Circuitry

A discrete circuit is composed of electronic components which are disparate, individual devices, also called discrete components. These can be “passive” components, like resistors, capacitors and inductors, as well as “active” components, which in our case are transistors. The opposite to this would be an integrated circuit, which uses operational amplifiers (Op-Amps) in the signal chain. Countless hours of listening tests and years of experience have shown us that even the very best Op-Amps do not tend to be so neutral, natural, dynamic or vivid. Standard phono pre-amplifiers with integrated circuits have a few tens or hundreds of components, but discrete designs will employ hundreds or thousands of components by comparison. That makes for an extended and more costly design process, but results in the best sound for your money.

Fully Balanced

The Phono Box RS2 employs a true fully balanced design principle. Balanced transmissions consist of a hot and a cold (also called + and -) signal. Both the + and – signal chains effectively carry the same musical information. A true balanced amplifier can now extract the final musical information out the +/- signals and subtract, remove, all noise that could potentially be added along the transmission. In a true, fully balanced amplifier, like the Phono Box RS2, the + and – sections of both the left and right channel are treated individually, which doubles the amplifier sections by 2 as a result.

Split passive EQ

The Phono Box RS2 uses split passive equalization for both of its RIAA and DECA curves. This is more costly to design and implement but ensures the most accurate representation of the ideal EQ curve. Split passive equalization allows for better impedance matching and lower deviation from the ideal RIAA or DECA curve.

Extreme cartridge loading options

No other phono-preamp in the world has such fine options of setting the gain like the Phono Box RS2. Very large ranges from 40dB (voltage amplification by 100x) up to 70dB (voltage amplification by 3690x) are possible.

Load impedance can be set continuously via potentiometer, a system invented by Pro-Ject Audio Systems. It allows you to seamlessly adjust the impedance during playback and immediately assess the impact of different loading options.

Cartridges, by nature, suffer from small imbalances between the left and right channels. To correct this the Phono Box RS2 introduces a new feature that is absolutely rare in this price category. A potentiometer allows you to adjust the exact center of the sound stage in ranges of 2dB to the left or right.

Steel/aluminium chassis

The Phono Box RS2 has a steel chassis which is covered by screwed aluminium panels. This construction brings very good rigidity and splendid isolation against interferences.

Power Box RS2 Phono – linear power supply upgrade

An outboard power supply with linear construction is even better, because it can offer much cleaner power. When you want to manufacture such clean and really high-end power supplies, you have to use a transformer with a very low core saturation and preferably with shielding between primary and secondary windings. Obviously, such a transformer becomes larger than one would expect. Also, much more expensive. That is why such a power supply requires a cabinet the size of the Phono Box RS2 itself. Our Power Box RS uni 1- & 4-way will be another step up for your Phono Box RS2 performance.

Features

• MM & MC capable
  
• Fully balanced, true dual mono design
  
• Fully discrete hardware design - NO Op-amps!
  
• Fully passive RIAA & DECCA equalisation
  
• Balanced XLR & unbalanced RCA In & Outputs
  
• Unique continously variable input impedance loading and channel balance control to match every cartridge to 100% (adjustment even while playing)
  
• Superior low noise / low distortion
  
• Metal casing protects against vibration and interference
  
• Available in silver or black

REVIEW & AWARDS

Pro-Ject Phono Box RS2 phono preamplifier - Read More

• On the MC rig, the RS2 seemed neutral, detailed and lively. It sounded clean, almost pristine.
• The sound with the MM setup was more midrange-focused, with good detail and musicality. I heard what I was used to hearing on familiar recordings – just more of it.
• The RS2 helped reveal a lot of information the cartridges unearthed from the grooves.
• Vocals and violin – indeed all the instruments – sounded rich, full, and substantial, yet studio-natural without oversaturated colors.
• The degree of detail seemed to increase, as did realism and clarity. The musicians‘ placement seemed to grow more spacious and specific.
• The accordion sounded realistic in timbre, its bellows sustaining and shifting. The pace and rhythm conveyed tango‘s tension.
• An increased sense of air gave most instruments pleasing purity, without excessive politesse. Piano key strikes sounded clean and refined.
• Bass notes sounded plump and punchy with more energy and impact on the attacks.
• I heard a trill I hadn‘t heard before. The instruments seemed better separated, with more air and expansion between them. The presentation felt more grounded and solid with better dimensionality, yet freed up with lively energy.
• Changing settings „on the fly“ was satisfying. Instant gratification.
• The RS2 could be viewed as an analog equivalent response to those desires for system tweaking: You can tailor your recordings‘ sound „on the fly“ without DSP." - Julie Mullins  

Pro-Ject Phono Box RS2: Review - Read More

"The Phono Box RS2 doesn’t stand out in any particular category but is an extremely capable performer across the board offering a very balanced sound that extracts the most music possible from the cartridge on the other end. It is in many ways, a caretaker or conservator of the music and a phono preamp that elevates the signal to the next part of the signal chain without losing any of the information or the soul of the music. Highly recommended.  " - Manel Segarra

PRO-JECT PHONO BOX RS2 Review – Keeping Balance - Read More

"An advanced and superb balanced-input phono preamplifier with deeply insightful sound. A must-have for top quality vinyl replay."

Test Phono Stage Pro-Ject Phono Box RS2: the gold digger - Read More

"With the Phono Box RS2, the leading analogue supplier Pro-Ject not only brings all its production technology capabilities into the ring, but also its great knowledge. The result is by far the most versatile phono stage in this class, which also carries this advantage into the sound performance. If you value dynamic accuracy in LP playback, the RS2 is the right choice.." - Andreas Günther

SPECIFICATIONS