Note: for the full suite of measurements from the SoundStage! Audio-Electronics Lab, click here.

Reviewers' ChoiceLast year I reviewed Pro-Ject Audio Systems’ X2 B turntable for SoundStage! Hi-Fi. The “B” indicates that the turntable can be run in a balanced configuration, provided the tonearm is fitted with a moving-coil cartridge (MC cartridges are inherently balanced). Since it came premounted with an Ortofon Quintet Red MC, I was mostly set up, except for one thing: I don’t own a balanced phono preamplifier. To remedy that, Gentec International (Pro-Ject’s Canadian distributor) provided me with a Phono Box S3 B phono stage and Connect it S mini XLR cable so I could evaluate the X2 B and S3 B in both single-ended and balanced configurations.


The X2 B’s good looks and clean, neutral sonics made it an easy recommendation. However, as much as I liked the turntable, it was the Phono Box S3 B that most surprised me, with its combination of great sound and remarkable feature set. In fact, I was so enthusiastic about the phono stage that I asked Gentec to send it to me again so I could review it on its own. As you’ll see, the S3 B deserves its own spotlight.


At $499 (all prices in USD), the S3 B’s price skews toward the entry-level segment of the market—some of the phono stages we review at SoundStage! Hi-Fi sit comfortably in the four-figure range. While the owner of a $500 turntable isn’t likely to partner it with a phono preamp of equal value, the S3 B isn’t out of the question for someone who’s invested $1K or more in a record player.

Constructed in Slovakia from a combination of electromagnetic-shielding aluminum and steel, the S3 B measures 8.1″W × 2.2″H × 6.4″D (including sockets) and weighs a smidgeon over two pounds (without its outboard power supply). Available in black or silver, this small box feels surprisingly sturdy. On its backside are balanced and single-ended inputs and outputs. The balanced input is a five-pin mini XLR while the balanced outputs are full-size XLR connectors.


Marketed by Pro-Ject as its “True Balanced Connection,” the Connect it S cable with five-pin mini XLR carries two impedance-matched signal conductors per channel, and one ground connection. When the balanced signals arrive at the phono preamplifier, they are received by a differential device that only responds to the difference in voltage between the two signal lines, thereby rejecting any noise that is identical on both wires.

Phono stages usually have few buttons, since adjustments are typically made using dip switches or jumpers on the circuit board itself (if you’re lucky you can access them on the outside, as on the iFi Audio iPhono3 Black Label phono stage). Happily, the S3 B isn’t like most phono stages. In fact, its best feature isn’t its balanced architecture, although I realize that this is easily its most sellable attribute for many people (including Pro-Ject’s marketing department). What I loved most about the Phono Box S3 B was the ability to match it to my cartridge and amplifier using a series of pushbuttons on the front panel, and then to effortlessly experiment with these settings. I’ve never been able to do this with a phono stage before, and after having had these adjustments at my fingertips, fiddling with dip switches or jumpers seems cumbersome now.


The pushbuttons control impedance, capacitance, and gain. There are five options for the input impedance: 10, 50, 100, 1k, and 47k ohms. Meanwhile, settings of 50, 150, 300, and 400pF are available for load capacitance. Gain can be set to 40, 45, 60, or 65dB, with an additional 6dB when it’s run balanced. A button that engages a subsonic filter with an 18dB/octave rolloff below 20Hz is also selectable via the front panel. A fifth button toggles between the single-ended and balanced inputs. Conveniently, the S3 B will store whatever settings were last used for each input, meaning that two turntables can be connected simultaneously.

The S3 B employs discrete rather than integrated circuits in its gain stages. As implied by the name, discrete circuits are made up of individual electronic components. An integrated circuit is a small semiconductor wafer on which are fabricated thousands (or millions) of resistors, capacitors, diodes, and transistors. Using separate components to construct the amplifier section costs more, but Pro-Ject believes it delivers the best sound.


For this review, the S3 B replaced a Lehmannaudio Black Cube phono stage in my system. It was connected to a Thorens TD 160 HD turntable featuring a modified Rega RB250 tonearm and Sumiko Songbird low-output MC cartridge using Kimber Kable Tonik RCA interconnects. Thorens RCA cables were used to link the S3 B with a Bryston B135 SST2 integrated amplifier. A set of Nirvana Audio Royale speaker wires terminated in spades delivered power to Monitor Audio Gold 300 5G tower speakers. All electronics were plugged into an ExactPower EP15A power conditioner-regenerator.

Single-ended sonics

Although I have a moving-coil cartridge mounted on my tonearm, my turntable doesn’t have a balanced output, so I could only evaluate the S3 B single-ended. I didn’t hear a difference between the balanced and single-ended inputs when I reviewed the X2 B / S3 B combo last year (heresy, I know), so my inability to use the latter’s balanced configuration was a nonissue for me.

Per Sumiko’s recommendations for the Songbird, I set the input impedance on the S3 B to 100 ohms and started with the gain at 60dB. Without music playing and the volume dial on my integrated amplifier set to 12 o’clock, there was a bit of static coming from the tweeters, so I tried the next lowest setting. With the gain now set to 45dB, I could turn the Bryston all the way up and hear almost nothing from the tweeters. I decided to leave it there and began playing music, finding that I needed to turn the B135 SST2 up to approximately two o’clock to get the volume I wanted.


This little story illustrates a minor quibble I have with the S3 B: while its ease of use is exceptional, I would like to see more increments for matching impedance and gain to your system. Going from a gain of 45dB to 60dB is a big jump. For finer adjustments, you’ll need to upgrade to Pro-Ject’s Phono Box DS3 B ($799), which adds two additional gain settings (50 and 55dB) and a potentiometer for continuous adjustment of load impedance.

I spent much of my time listening to classical music through the Pro-Ject, including Franz Liszt (Sony Classical MOVCL070): a collection of solo piano works performed by Khatia Buniatishvili. On the first movement of Liszt’s Sonata in B Minor, I didn’t just hear Buniatishvili’s playing; I felt it. What I mean is that I could appreciate her touch as she performed the piece. The delicacy with which some keys were struck contrasted sharply with the intensity and vigor of other notes. Even during the most frenzied passages, every note was distinct, so that it was easy to “see” what her hands were doing. The noise floor of this recording is so low that with a curtain in front of the system, listeners might be tricked into thinking they were hearing a digital source. Well, almost.

Recorded in Berlin’s historic Meistersaal concert hall, the venue’s hard, wooden surfaces and high, coffered ceiling don’t factor into the sound as much as one might expect. Franz Liszt seems to capture the direct sound of the piano more than it does the latent reverberations from the room. The effect is to bring Buniatishvili’s performance into the listening room as opposed to transporting the listener to the recording venue.


While I certainly enjoyed the virtuosity of Liszt’s compositions and the “wow” factor of hearing so many notes played at rapid-fire tempo, my attention was equally drawn to quieter moments on this record. I found myself lingering on the decay of the notes into what was essentially a black background. If the S3 B could be said to have had any mark on the music, it was in the way it allowed me to hear such an incredible degree of detail and to appreciate the spaces between the notes. As I wrote during my first encounter with this component, the S3 B has no real character to speak of. You wouldn’t buy this phono stage if you had a lean-sounding analog front end that you wanted to sound fuller. The S3 B isn’t a tone control.

Moving on to Herbert von Karajan’s 1962 recording of Beethoven’s Symphony No. 5 with the Berlin Philharmonic Orchestra (Deutsche Grammophon 138 804), the music is full of drive and intensity right from its famous opening four notes. In the final movement, the blare of the brass is quickly joined with the swell of the orchestra as if to herald some exuberant triumph. This music is dynamic and captivating, and the S3 B simply conveyed it as such. As on Franz Liszt, it contributed nothing to the music, other than rendering an extremely low noise floor that provided a quiet backdrop from which detail and nuance could emerge.

The character of this symphony was elevated entirely when I put a more recent recording onto the platter. Featuring the Vienna Philharmonic conducted by Carlos Kleiber (Deutsche Grammophon 479 3188), this modern pressing has less surface noise than the HvK recording. In musical terms, this means that the end of the third movement possesses a greater sense of stillness and tension before the explosive finale. Whereas the Berlin Philharmonic sounds somewhat congested in busier passages, the sections of the Vienna Philharmonic appear to have more space around them, making each more distinct, more vivid. This is a function of the recording’s quality, but once again the S3 B’s strikingly quiet demeanor emphasized the differences.


Next, I reached for one of the better-sounding jazz recordings in my collection: Charles Mingus’s Mingus Ah Um (Columbia Records / Legacy Recordings 8697-335681). The opening track, “Better Git It in Your Soul” really hustles. The fast, frenzied tempo is instantly infectious. Mingus and his group sound so dialed in, and their playing is so tight, they make what they are doing seem easy. Through the S3 B, the musicians were spread precisely across a wide and deep soundstage that extended well behind the plane of the speakers. When the music suddenly drops out and handclaps are heard emanating from the right side of the stage, accompanied by a saxophone opposite them, the sound was so utterly clean and transparent that I almost felt I could reach out and touch it. This is an exceptional album and a stellar recording, but it still requires a resolving system to let you clearly hear what’s going on. At $499, the S3 B didn’t concede much to phono stages I’ve auditioned that cost several times more than that.

On “Goodbye Pork Pie Hat,” a tribute to saxophonist Lester Young, the tone immediately pivots from the high-energy vibes of “Better Git It in Your Soul” toward a more somber, melancholic mood. The sense of empty space in the music was almost a metaphor for the feeling evoked by this track, and again it was convincingly communicated by the Pro-Ject, due in large part to its low noise floor.

On the next track, “Boogie Stop Shuffle,” the music swings back to a high tempo. Its quick pace was served well by the S3 B, which again imparted nothing to the sound. If you’re looking for a phono stage that will add a lusher character to your analog setup, this isn’t it. The S3 B’s dry demeanor is really intended for listeners who are already happy with their turntable and simply want to preserve its character.


I decided to play the Bill Evans Trio’s Bill Evans at Town Hall, Volume One (Verve V6 8683 E) after reading Joseph Taylor’s recent piece on SoundStage! Xperience on the slowdown of the vinyl boom, simply because his article featured a picture of the record. On this recording, the piano isn’t the last word in detail, but through the Pro-Ject it sounded convincing nonetheless. The opening tune, “I Should Care,” jumped from the grooves of the record, led by the vibrant notes coming from the strings of the piano. Chuck Israels’s double bass imparted a solid presence, while Arnold Wise’s drum kit was lively—the cymbals having a crisp air about them. Due in no small part to the precise layout of the musicians across the stage, Town Hall helps transport the listener to the concert. The crowd is surprisingly quiet during the show, particularly while Evans plays. It’s in this silence that I could almost “hear” how immersed they are in Evans’s playing. This was most evident on the 13-minute solo that concludes the record. As its title suggests, “Solo—In Memory of His Father, Harry L. Evans, 1891–1966” is an emotional tribute to Evans’s dad, who had passed away only two weeks before the concert. My Canadian pressing is nearly six decades old, and although it’s in good condition, this track especially has its share of crackles and pops. Even so, the silence of the crowd was clearly presented by the S3 B, making their captivation almost palpable.


The S3 B had replaced the Lehmannaudio Black Cube phono stage that I’ve been using for over a decade. The Black Cube was reviewed on the SoundStage! Network back in 1998, when it sold for $695. Perhaps as a testament to the enduring quality of its design, the same model is still sold today. Featuring a bulky outboard power supply, the Black Cube is a rather simple affair, using a combination of internal dip switches and jumpers to match it to the cartridge. As this is still the case for most phono stages in 2023, this is only an observation—it’s not a critique of the Black Cube.

Moving on from the jazz and classical music I’d mostly used to this point, I changed genres. The White Stripes’ Elephant (Third Man 63881-27148-1) is easily one of the best-sounding rock albums in my collection. When a record’s liner notes go to the effort of pointing out that the music was recorded on eight-track reel-to-reel tape and that computers weren’t used during the writing, recording, mixing, or mastering, it’s safe to say the band’s two musicians have some strong convictions about analog production. Starting with the Lehmannaudio Black Cube, the drum kit popped from the mix. On “Ball and Biscuit,” the kick drum was punchy, the cymbals were crystalline, the electric guitar’s highs soared, and there was a ton of space on the stage. Elephant is well recorded, managing to combine a gritty character with exceedingly clean and well-sorted sonics. With its own commendably low noise floor, the Black Cube was lucid, rendering a wide, deep stage that only sounded better as I turned the volume higher.

With the Black Cube, the drum kit had a bit more weight and a slightly meatier presentation than it had through the S3 B. With the Pro-Ject, I found myself more drawn to the guitar, which emerged more from the mix—partly because I was less focused on the drums. The S3 B wasn’t lean per se, but the Lehmannaudio had more power in the low end, while the Pro-Ject tended toward a drier character. Elephant sounded great through both phono stages, although the Black Cube’s heftier bass better suited this record.

Returning to Franz Liszt, I couldn’t choose a winner between the Black Cube and the S3 B. Both offered a clear window on Buniatishvili’s intimate-sounding performance, with similar stage depth and low noise floor. The Black Cube drew a bit more attention to piano’s lowest registers compared to the S3 B, whose presentation in this region was drier. This was similar to what I heard on the White Stripes album, though I need to stress that these weren’t night-and-day differences. In fact, in most respects, but particularly regarding resolution, I found that the two phono stages performed similarly.

What most distinguished the Lehmannaudio and Pro-Ject wasn’t their sound, but rather their functionality. If you’ve got a balanced turntable, the Black Cube can’t make use of the connection. Furthermore, the German phono stage has nowhere near the ease of use of its Austrian counterpart. As a listener, and especially as a reviewer, the S3 B’s feature set tips the balance heavily in its favor. Given that I enjoyed the sound of both phono stages, I’d choose the Pro-Ject over the Lehmannaudio.


Since I felt Pro-Ject’s Phono Box S3 B deserved its own review, it isn’t surprising that I have a lot of positive things to say about its performance. Is it the best-sounding phono stage you can buy for under $500? I can’t answer that because it has a lot of competition at that price, much of which I haven’t heard. However, I’d be willing to wager that it can hold its own sonically against anything near its price point. I say this because I listened to it alongside Saturn Audio’s 401 phono stage, and it wasn’t embarrassed. I preferred the 401 (which is still the best-sounding phono stage I’ve ever heard in my system), but its $2900 price tag keeps it out of my reach. Besides, at a fraction of the Saturn’s price, the Pro-Ject is more user-friendly.


This is where the S3 B is without peers. There simply aren’t any European-made balanced phono stages at this price that can be so easily matched to one’s cartridge and amplifier. The term “benchmark” or “reference” is often thrown about carelessly in product reviews. However, the S3 B is a benchmark product. It’s unlikely that a company without Pro-Ject’s manufacturing expertise and scale could build something similar for the same price. Its exceptional functionality establishes a new bar for what a customer can expect in a $500 phono stage. My hope is that other companies will follow suit, but for now, the S3 B sits alone as an incredibly special product. Bravo, Pro-Ject!

. . . Philip Beaudette

Note: for the full suite of measurements from the SoundStage! Audio-Electronics Lab, click here.

Associated Equipment

  • Speakers: Monitor Audio Gold 300 5G.
  • Phono stage: Saturn Audio 401, Lehmannaudio Black Cube.
  • Integrated amplifier: Bryston B135 SST2.
  • Analog source: Thorens TD 160 HD turntable, Rega Research RB250 tonearm, Sumiko Songbird moving-coil cartridge.
  • Speaker cables: Nirvana Audio Royale.
  • Power conditioner: ExactPower EP15A.

Pro-Ject Audio Systems Phono Box S3 B Phono Preamplifier
Price: $499.
Warranty: Two years, parts and labor.

Pro-Ject Audio Systems
Margaretenstrasse 98
A-1050 Vienna


Canadian distributor:
Gentec International
90 Royal Crest Court
Markham, Ontario L3R 9X6
Phone: (905) 513-7733


US distributor:
Fine Sounds Americas (formerly Sumiko Audio)
9464 Hemlock Lane North
Maple Grove MN 55369
Phone: (510) 843-4500
Fax: (510) 843-7120