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Based on price data from 1 merchant for "Pro-Ject Phono Box S3 B Balanced MM/MC Phono Preamp". Prices shown reflect NEW condition. Tracking began Apr 2, 2026.

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Description

Delve into the world of high-fidelity audio with the Pro-Ject Phono Box S3 B Balanced MM/MC Phono Preamp, a gateway to true sonic excellence. Engineered for both budding audiophiles and seasoned vinyl enthusiasts, this preamp offers a fully balanced design that elevates your vinyl experience to new heights. The Pro-Ject Phono Box S3 B is a marvel of meticulous engineering, featuring a symmetrical gain stage and semi-passive RIAA equalization for hyper-accurate frequency reproduction with minimal noise and distortion.

The Phono Box S3 B excels in its dual-mono design, ensuring maximum channel separation, which offers a pristine audio path. Its fully discrete audio circuitry eliminates the need for integrated circuits, providing an ultra-clean signal for your turntable. Designed to accommodate both moving magnet and moving coil cartridges, this preamp offers selectable gain and switchable input impedance loading, giving you the flexibility to tailor your sound.

Wrapped in a robust steel chassis with aluminum panels, the Phono Box S3 B not only looks striking but also provides excellent protection against interference. With a subsonic filter to eliminate unwanted rumble, your listening experience remains uninterrupted and clear. Elevate your analog journey with the Pro-Ject Phono Box S3 B and explore the depths of true balanced audio.

Key Features:

  • Fully balanced design with XLR connectors for superior noise rejection
  • Symmetrical gain stage for optimal signal-to-noise ratio
  • Semi-passive RIAA equalization for accurate frequency reproduction
  • Fully discrete audio circuitry for low noise and distortion
  • Dual-mono design for maximum channel separation
  • Compatible with moving magnet and moving coil cartridges
  • Selectable gain and switchable input impedance loading
  • 20Hz subsonic filter to eliminate low-frequency rumble
  • Heavy aluminum casing for robust interference protection

Product specs

Preamp Type True Balanced Phono Preamplifier, Black
Number of Channels Dual Mono
EQ RIAA (semi-passive)
Analog Inputs 1 x 5-pin Mini-XLR, 1 x Dual RCA Phono (MM/MC)
Analog Outputs 2 x XLR, 1 x Dual RCA Phono
Frequency Response 20Hz to 20kHz
Power Source 18V/500mA DC Power Supply (included)
Height 2.16"
Depth 8.11"
Width 6.02"
Weight 2.05 lbs

FAQs

What types of cartridges is the Pro-Ject Phono Box S3 B compatible with?

The Pro-Ject Phono Box S3 B is compatible with both Moving Magnet (MM) and Moving Coil (MC) cartridges, making it versatile for various turntable setups.

What is the benefit of the true balanced design in the Pro-Ject Phono Box S3 B?

The true balanced design helps reduce noise and interference, providing a cleaner, more detailed sound, especially important for high-fidelity audio systems.

What are the main input and output options on the Pro-Ject Phono Box S3 B?

The Pro-Ject Phono Box S3 B features 1 x 5-pin Mini-XLR and 1 x Dual RCA Phono for inputs, and 2 x XLR and 1 x Dual RCA Phono for outputs, offering flexible connectivity options.

Does the Pro-Ject Phono Box S3 B include a power supply?

Yes, the Pro-Ject Phono Box S3 B comes with an 18V/500mA DC power supply, ensuring it's ready to use out of the box.

What is the frequency response range of the Pro-Ject Phono Box S3 B?

The frequency response of the Pro-Ject Phono Box S3 B is 20Hz to 20kHz, covering the full range of human hearing for accurate audio reproduction.

hxos plus

hxos plus

The most inexpensive Balanced phono stage in the market 2022 | Pro-Ject Phono Box S3 B

Video thumbnail for The most inexpensive Balanced phono stage in the market 2022  | Pro-Ject Phono Box S3 B by hxos plus

The most inexpensive Balanced phono stage in the market 2022 | Pro-Ject Phono Box S3 B

hxos plus

hxos plus

Video thumbnail for 🥶Phono Stage END GAME?? by ABX Audiophiles

🥶Phono Stage END GAME??

ABX Audiophiles

ABX Audiophiles

Video thumbnail for Phono Box S3 B (Balanced) | Pro-Ject | Unboxing by AUDIO CENTER POLAND

Phono Box S3 B (Balanced) | Pro-Ject | Unboxing

AUDIO CENTER POLAND

AUDIO CENTER POLAND

Video thumbnail for Pro-Ject Phono Box S3 B Review - Kronos AV Review Diaries by Kronos AV

Pro-Ject Phono Box S3 B Review - Kronos AV Review Diaries

Kronos AV

Kronos AV

Reviews

PROS

  • Seamless integration with Pro-Ject turntables, enhancing audio performance

  • Offers clear, dynamic sound with more sound color than integrated preamps

  • Front push button selections for convenient settings adjustments

  • Supports both MM and MC cartridges with ease

  • Full balanced audio connection capability for a higher fidelity experience

  • Considered an "end-game" phono stage for many, despite mid-range marketing

  • Easy to install with versatile cartridge support

CONS

  • More expensive compared to some competitors like the Parasound zphono

  • Lacks the deeper bass and wider soundstage compared to some alternatives

Owner Insights

We analyzed real musician discussions from forums and Reddit to find what players love, question, and tweak about Pro-Ject Phono Box S3 B Balanced MM/MC Phono Preamp.

Features and functionality

  • The Pro-Ject Phono Box S3 B includes RCA connectors, offering flexibility beyond its balanced inputs for various user setups.

    Source

Comparisons

  • The Pro-Ject Phono Box S3 B is noted for flexibility and ease of use but is considered less price-competitive compared to options like the iFi Zen Phono if balanced I/O isn't needed.

    Source

User experience

  • Owners report that standalone phono stages, such as the Pro-Ject, generally outperform onboard alternatives in terms of audio quality and user satisfaction.

    Source

Critic Reviews

SoundStage! Hi-Fi | SoundStageHiFi.com - Pro-Ject Audio Systems Phono Box S3 B Phono Preamplifier

soundstagehifi.com

The Pro-Ject Phono Box S3 B impresses with its remarkable blend of sound quality and features at a modest $499. Its standout capability is the user-friendly adjustment of impedance, capacitance, and gain via front panel pushbuttons, allowing seamless cartridge matching. The S3 B's balanced connectivity and low noise floor deliver detailed, transparent audio without coloration, making it a neutral force in your signal chain. However, it could benefit from finer gain adjustments, as the jump from 45dB to 60dB is significant. Despite this minor quibble, its functionality sets a high bar for affordable phono stages, making it a benchmark in its price range.

positive

Pro-Ject Phono Box S3 B Audiophile Phonostage Reviewed

futureaudiophile.com

The Pro-Ject Phono Box S3 B Phonostage shines with its balanced input and output options, offering audiophiles a taste of high-end features at a mid-range price. Its configurable impedance, capacitance, and gain settings allow users to fine-tune sound quality to match their cartridge, enhancing vinyl playback significantly. While the lack of a true balanced performance without conversion is a slight drawback, the value it offers is impressive, especially with features often found in pricier models. Finding the right cables can be a hassle, and its absence of a volume control means a traditional preamp is necessary, but these are minor quibbles for a unit that delivers such robust sound performance. For those looking to elevate their vinyl listening experience without breaking the bank, the Phono Box S3 B is a compelling option that won't disappoint.

positive

Pro-Ject Phono Box S3 B Phono Preamplifier and X2 B Turntable Review - HomeTheaterHifi.com

hometheaterhifi.com

Pro-Ject's Phono Box S3 B and X2 B turntable duo delivers a lively and engaging vinyl experience. The Phono Box S3 B stands out with its on-the-fly cartridge adjustment, a rarity at its price point, and offers a noise-resistant balanced connection option. Meanwhile, the X2 B turntable impresses with its stable speed and a solid upgrade path, thanks to the Superpack option. The only minor letdown is the absence of a mono switch on the preamp. Overall, for $2,298, this combo is a fantastic investment for vinyl enthusiasts seeking quality sound and future-proofing.

positive

Pro-Ject Phono Box S3 B Review: A Balanced Masterpiece at an Unbeatabl — The Audio Tailor

theaudiotailor.com.au

A masterstroke in phono preamplification, the Pro-Ject Phono Box S3 B balances high-end tech with accessibility. Its true balanced connection ensures superior signal integrity and a remarkably low noise floor, offering sound quality typically reserved for pricier units. The robust build and versatile adjustment options cater to discerning audiophiles. However, its premium price and need for balanced cables may overextend basic setups. For those seeking to elevate their vinyl experience without breaking the bank, this compact powerhouse is a compelling choice.

positive

SoundStage! Hi-Fi | SoundStageHiFi.com - Recommended Reference Component: Pro-Ject Audio Systems Phono Box S3 B Phono Preamplifier

soundstagehifi.com

The Pro-Ject Phono Box S3 B is a gem in the phono preamp world, offering a remarkable blend of affordability and high-end features. Its flexible design supports both MM and MC cartridges, with an intuitive front panel for easy adjustments—a refreshing change from cumbersome dip switches. While its balanced connections are a standout, the S3 B truly shines with its neutral sound and transparency, delivering a clean, uncolored audio experience. Though it won’t add warmth or character, it excels in precision and low noise, rivaling pricier competitors. At $499, it’s a no-brainer for audiophiles seeking clarity without breaking the bank.

positive

Pro-Ject X2 B / Phono Box S3 B review: balanced through and through | What Hi-Fi?

whathifi.com

Pro-Ject X2 B/Phono Box S3 B Turntable/Phono Preamp | Hi-Fi News

hifinews.com

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