Préamplificateur phono Pro-Ject Phono Box S2 Ultra

The Pro-Ject Phono Box S2 Ultra phono preamp is a bit puzzling because, from the outside (aside from the screen-printed text), nothing sets it apart from the Phono Box S2.

We had a hard time understanding this product and its appeal… We had to take it apart, examine it, and run all kinds of tests to justify its price (which we’re probably the only ones to have done).

It’s supposedly based on the Phono Ultra 500, which was reportedly released as a limited edition. So limited that we’ve never even seen one!

Pro-Ject Phono Box S2 Ultra: Housing

It features the same non-magnetic aluminum housing as the Phono Box S2 model, along with the same connectors and switches.

The difference, then, lies inside.

Pro-Ject Phono Box S2 Ultra: circuitry

Pro-Ject has redesigned the Phono Box S’s circuitry by removing all integrated circuits (op-amps) and replacing them with discrete components (transistors).

All the capacitors have been replaced with “polystyrene” capacitors, which is a wise choice for a phono preamp.

The RIAA equalization has been separated, and the equalization points have been set with great precision. Pro-Ject claims an RIAA curve with an accuracy of less than 0.4 dB from 20 Hz to 20,000 Hz!

The gain is adjustable in four steps (40, 43, 60, and 63 dB). The load is also adjustable depending on the cartridge (10 ohms, 100 ohms, 1 kOhm, and 47 kOhm).

The Phono Box S2 Ultra features a switchable subsonic filter with an attenuation of 18 dB at 20 Hz.

Pro-Ject Phono Box S2 Ultra: Review and Listening Impressions

So we paired the Pro-Ject Phono Box S2 Ultra with an MM cartridge and a low-output MC cartridge. And, of course, we compared it to its little brother, the Phono Box S2.

Clearly, with a mid-range MM cartridge, the differences are barely noticeable... It wasn’t until we paired it with an Ortofon 2M Black MM cartridge that the Phono Box S2 Ultra really made a difference.

In fact, it’s with a low-output MC cartridge that you can truly appreciate the quality of its components. With, for example, an Ortofon Quintet Black S MC cartridge or a Hana SL MC cartridge, the sound quality is remarkable for its finesse and clarity.

The dynamics and transparency are surprising.

It offers the neutrality and articulation found in some phono preamps costing two or three times as much.

Note also that it requires a break-in period of over 50 hours to truly come into its own.

As you can see, this Pro-Ject Phono Box S2 Ultra phono preamp is a high-performance version of Pro-Ject’s best-seller!

It’s an excellent phono preamp for those using a phono cartridge that’s already of a certain quality. It lets you get the most out of excellent entry-level, low-output MC cartridges without breaking the bank.

AWARDS:

Hi-Fi Choice - Recommended

Hi-Fi World - *****

FAQ: Everything you need to know before buying the Pro-Ject Phono Box S2 Ultra phono preamp

What is the real difference between the Phono Box S2 and the Phono Box S2 Ultra?

Outwardly nothing changes, but inside Pro-Ject removed all the integrated circuits (op-amps) and replaced them with discrete components (transistors), and all the capacitors were replaced with polystyrene models, with an RIAA curve stated to be accurate to within 0.4 dB from 20 Hz to 20 kHz. We had to pair it with an Ortofon 2M Black MM cartridge for the Phono Box S2 Ultra to really make a difference. We therefore paired the Pro-Ject Phono Box S2 Ultra with an MM cartridge and a low-output MC. As you will have gathered, this Pro-Ject Phono Box S2 Ultra phono preamp is a souped-up version of Pro-Ject's best-seller.

With which type of cartridge does this Ultra version really make a difference?

It is above all with a good-quality low-output MC cartridge, such as an Ortofon Quintet Black S or a Hana SL, that you hear the difference in refinement and fluidity brought by the high-end components. With a mid-range MM cartridge, the gap remains barely perceptible, except with an Ortofon 2M Black. The loading is also adjustable according to the cartridge (10 Ohm, 100 Ohm, 1 kOhm and 47 kOhm). Note too that it needs a break-in of more than 50 hours to really express itself.

How long does it take for this preamp to reach its full potential?

We recommend a break-in of more than 50 hours for the Phono Box S2 Ultra to express itself fully, which is longer than for the standard version. The capacitors have all been replaced with "polystyrene" types, which is wise in a phono preamp. It will be an excellent phono preamp for those using a cartridge already of a certain quality level. The Pro-Ject Phono Box S2 Ultra phono preamp is a little curious because, from the outside (apart from the printing), nothing distinguishes it from the Phono Box S2.

What gain and loading settings does it offer?

The gain is adjustable in four steps (40, 43, 60 and 63 dB) and the loading in four values (10, 100, 1k and 47k ohms), with a switchable subsonic filter at 18 dB of attenuation at 20 Hz. We had trouble understanding this product and its purpose: we had to dismantle it, examine it and run tests every which way to justify its price. It is said to be based on the Phono Ultra 500, reportedly released as a limited series.