Pro-Ject Audio Systems have sold over 500,000 of their Phono Box phono stages; and to mark this milestone the company are releasing their first op-amp-less phono stage, and it’s available in two different versions.  

The Phono Box S2 Ultra (£200.00 SRP) replaces the Phono Box DS and DS+ models in the Pro-Ject range. It utilises a fully discrete electronic layout without the use of operational amplifiers (op-amps). Op-amps are commonly used in phono stages to increase the quiet sound from a pick-up cartridge to a level that modern amplifiers can use. However, by shifting away from that technology, Pro-Ject are able to produce a device with a “warm, harmonious sound” adding “The split RIAA equalisation circuit enables pin-point accuracy of the RIAA curve and the introduction of a subsonic filter ensures your music sounds right in any environment.” With a series of dip-switches on the bottom of the solid metal casework, there are multiple settings for impedance (MC), capacitance (MM) and gain – so any modern Moving Magnet or Moving Coil cartridge is easy to accommodate.

The Phono Box Ultra 500 (£299.00 SRP) makes use of the same technologies as the Phono Box S2 Ultra, with its fully discrete layout and precise RIAA equalisation. Where it takes a further leap forward is in the mechanical construction. Finished with a chrome surface, the chassis is made from copper for its heightened ability to protect against high-frequency interference. It is supplied in a wooden display box and limited to 500 pieces worldwide.

The Phono Box S2 Ultra and Phono Box Ultra 500 will be available across the UK during November. Available in Black or Silver finish (Phono Box S2 Ultra only).  

Technical Information

Input Impedance: 10 / 100 / 1k / 47kΩ

Input Capacitance: 100 / 220pF

Gain Switch: 40 / 43 / 50 / 53 / 60 / 63dB

Subsonic Switch: -18dB @ 20Hz

Signal-to-Noise Ratio: -89dB V (MM)

THD: 0.00052%

RIAA Accuracy: < 0.4dB / 20Hz – 20kHz

In/Out Sockets: 1 x Pair RCA

Power Consumption: 18V / 80mA

Outboard PSU:  18V / 500mA

Dimensions (W x H x D):  103 x 37 x 119mm

Colour: Black or Silver (Phono Box S2 Ultra)

Chrome (Phono Box Ultra 500)

Weight (Without PSU)570g (Phono Box S2 Ultra), 700g (Phono Box Ultra 500)