At a glance
Expert’s Rating
Pros
- Supports two turntables
- Balanced connections really do improve sound
- Also offers stellar audio if you’re using its RCA inputs
Cons
- Requires a turntable with XLR outputs to experience its best features
- Expensive if you’re not using its balanced connection features
Our Verdict
The Pro-Ject DS3 B incorporates technology from high-end phono preamplifiers, bringing the balanced input listening experience to a far larger audience.
Pro-Ject’s Phono Box line of phono preamplifiers feature balanced inputs and outputs and discrete circuit design, the kind of high-end tech that hardcore audiophiles prize, but in products priced for a much broader audience.
There are two new models: the Phono Box S3 B ($499) and the Phono Box DS3 B ($799), and Pro-Ject suggests pairing either preamp with its outstanding $2,699 X8 turntable (you can read our Pro-Ject X8 review at the preceding link), another piece of high-end home audio gear that features high-end technology at less-than-stratospheric prices.
The Phono Box DS3 B is reviewed here, but the two devices share a lot of the same tech, so we’ll look at the Phono Box S3 B, compare it to the DS3 B, and then dig into how the higher-end box sounds.
Phono Box S3 B
The Pro-Ject Phono Box S3 B phono preamp is the less-expensive sibling ($499) to the model DS3 B reviewed here ($799).
Pro-Ject Audio Technology
The Phono Box S3 B allows you to connect two turntables at once and stores the preferred settings for each turntable. It’s built with a steel and aluminum chassis and is available in either silver or black. You can use either a moving magnet (MM) or moving coil (MC) cartridge with this phono stage.
There’s a dual mono design features both RCA inputs and a 5-pin mini XLR balanced input. There are both RCA and balanced XLR outputs. Its balanced design features two symmetrical signal chains and two discrete amplifier sections, engineered to remove noise and offer the cleanest phono signal possible.
Phono Box DS3 B
Balanced inputs/outputs and the large potentiometer shown here are the primary differentiators between the Pro-Ject Phono Box DS3 B and the less-expensive S3B.
James Barber/Foundry
The Phono Box DS3 B integrates all the technology from the SB3 and adds in a few extra features. The DS3 B also comes in silver or black, but you can buy wooden side panels ($129) that attach magnetically to the sides of the unit. There are walnut panels that work with either color or a dark eucalyptus panel for the silver unit.
The Phono Box DS3 B uses an external power adapter to further reduce the potential for interference. The unit allows tighter and continuous control over load impedance with a potentiometer control on the front of the device.
How is the DS3 B built?
The unit is 8-1/8 x 2-7/8 x 8-1/8 inches (WxHxD) and weighs 3.26 lbs. You get balanced XLR inputs and outputs, plus unbalanced RCA inputs and outputs. That setup allows you to connect two turntables at once, one with XLRs and one with RCAs.
Pro-Ject has incorporated technology from its $1,999 Phono Box RS 2 into the DS3 B, most notably a potentiometer on the front of the unit that allows for smooth impedance adjustment for low-output moving coil cartridges. That means the DS3 B can handle pretty much whatever exotic cartridge you want to use in a balanced-output setup.
Pro-Ject went with a discrete circuit design, which the company claims offers a more neutral sound that what’s possible with integrated circuits. There’s a subsonic filter to reduce low-frequency rumble, and the steel and aluminum chassis is designed to shield the internal circuitry from electromagnetic interference and vibration.
Pro-Ject elected to use a discrete circuit design, as opposed to using integrated circuits to build the Phono Box DS3 B. This necessarily increases the cost and complexity of manufacturing, but delivers higher performance.
Pro-Ject Audio Technology
There’s also a button on the unit to activate a subsonic filter at 20Hz to suppress low-frequency interference signals. The Loading Ohms button’s Variable setting allows the unit’s input impedance to be changed to accommodate low-output moving coil cartridges.
The Input button switches between the XLR and RCA inputs, and the unit remembers your settings for each if you’re using two different turntables.
How does the Phono Box DS3 B sound?
Listening to an original pressing of The Rolling Stones’ 1978 LP Some Girls was a good way to explore just what the Phono Box DS3 B can do. I used the Pro-Ject X8 turntable with a Sumiko Moonstone MM cartridge and first listened with a NAD Phono Preamp PP-1 through a NAD Stereo Preamplifier S100, a NAD Monitor Series Amplifier 2400, and a pair of vintage Bowers & Wilkins P5 floor-standing speakers.
The Pro-Ject Phono Box DS3 B phono preamp lets you mix and match inputs and outputs if you’re using a single turntable.
James Barber/Foundry
The NAD phono stage is a vintage unit that was a great entry-level choice in its day and uses RCA inputs and outputs. Once I switched over to the RCA connections on the Phono Box DS3 B, the differences were startling. There was markedly more detail and separation between instruments in the mix. Guitars that had previously bled together in songs like “When the Whip Come Down” and “Before They Make Me Run” are identifiable as individual instruments. The overall mix retains that warm analog sound with an added layer of detail.
Switching to a Sumiko Blue Point No. 3 MC cartridge on the X8 turntable and swapping out the RCAs for an XLR cable, the Phono Box DS3 B sounded even better. The balanced outputs combined with the moving coil cartridge to reveal the sort of detail that vinyl aficionados like to champion when they declare that LPs are better than any digital format.
Do you need a phono preamp with balanced inputs?
Under ideal conditions with the right gear and a great pressing, vinyl can strike an emotional chord in listeners that no other playback experience can match. Unfortunately, those ideal conditions usually come with an astronomical price tag.
The Pro-Ject Phono Box DS3 B combined with the X8 turntable is by far the best listening experience I’ve had with a turntable setup that costs less than $10,000. If you’re not ready to make the investment in a balanced turntable, the DS3 B would be an excellent placeholder investment, since it does a fantastic job with the unbalanced RCA inputs and outputs.
Pro-Ject has delivered a versatile phono preamp with remarkably neutral and detailed sound. It’s worth the investment even if you’re using it with the most basic setup possible, and it becomes an outstanding value once you take advantage of everything it can do.
