Pro-Ject
Pro-Ject Phono Box S3 B Balanced MM/MC Phono Preamp
Best balanced phono preamp for serious vinyl enthusiasts seeking pristine audio.
Experience superior vinyl playback with the Pro-Ject Phono Box S3 B, a fully balanced MM/MC phono preamplifier. This compact unit boasts Pro-Ject's True Balanced Connection technology, previously found only in high-end models. Its robust steel and aluminum casing shields against interference, ensuring pristine audio. Connect up to two turntables, with memory for individual settings. The discrete, symmetrical gain stage and semi-passive RIAA equalization deliver exceptionally clean sound, revealing the finest musical details from your records.
$499.00
Owner Satisfaction
4.6
/ 5
Category Rank
303
/ 466
#303 in Phono Preamps
Price vs Category Average
-93%
Below average
Input impedance
1050100147
/ , , , k, k ohms
Who it's for
- Audiophiles seeking a noise-free, balanced signal path
- Vinyl collectors using diverse MM and MC cartridge setups
- Listeners demanding high-fidelity, transparent sound quality
Who should skip it
- Budget-conscious buyers lacking balanced audio equipment
- Users who frequently swap cartridges and dislike manual adjustments
- Purists preferring integrated power supplies for noise reduction
Performance breakdown
Balanced Signal Integrity
True balanced circuitry minimizes noise for a remarkably clean, interference-free signal.
Cartridge Versatility
Extensive impedance and capacitance settings accommodate almost any MM or MC cartridge.
Build Quality
Robust steel and aluminum casing provides excellent shielding and long-term durability.
Operational Flexibility
Dual inputs with memory settings make switching between turntables completely effortless.
Sonic Precision
Discrete gain stages and accurate RIAA equalization reveal deep, nuanced musical detail.
Ease of Adjustment
Front-panel controls allow for quick, tactile tuning without digging through menus.
Key Specs
Input impedance
10, 50, 100, 1k, 47k ohms
Input capacitance
50, 150, 300, 400 pF
Gain (+ 6dB using XLR Out)
40, 45, 60, 65 dB
SNR MM (40dB)
103dBV, 110dBV - A weighted
SNR MC (60dB)
85dBV, 90dBV - A weighted
THD at 1 kHz
<0.001% MM, <0.005% MC
THD (20Hz-20kHz)
<0.008% MM, <0.01% MC
RIAA-equalization curve accuracy
<0.3dB / 20Hz - 20kHz
Features
- Fully balanced MM/MC phono preamplifier
- True Balanced Connection technology
- Dual turntable input with memory
- Discrete, symmetrical gain stage
- Semi-passive RIAA equalization
- Superior low noise and distortion
- Robust steel and aluminum casing
- Easy front-panel adjustments
What customers say
Consumers consistently praise the Phono Box S3 B for delivering exceptional sound quality and remarkable value. The balanced connectivity is frequently highlighted as a game changer, offering a noticeable reduction in noise floor and a richer, more detailed presentation. Users appreciate the flexible gain and impedance settings, making setup straightforward for both moving magnet and moving coil cartridges. This preamp is viewed as a substantial, affordable upgrade that elevates the vinyl listening experience significantly.
Know before you buy
True Balanced Connection uses a 5-pin mini XLR input to carry the signal from your turntable to the preamp in a fully balanced path. This design significantly reduces electromagnetic interference and noise, resulting in a cleaner, more dynamic soundstage compared to standard RCA connections.
Yes, the Phono Box S3 B is compatible with both MM and MC cartridges. You can easily adjust the gain and loading settings on the front panel to match the specific electrical requirements of your cartridge.
Yes, you can connect two turntables simultaneously—one via the 5-pin mini XLR input and one via the RCA jacks. The unit features memory, so it will remember your individual gain and impedance settings for each input when you switch between them.
Yes, it includes a switchable subsonic filter that operates at 20Hz with an 18dB/octave slope. This helps protect your speakers from excessive woofer excursion caused by warped records or low-frequency rumble.
No, all adjustments for impedance, capacitance, and gain are conveniently located on the front panel. You can fine-tune your settings on the fly without needing any tools or internal modifications.
The discrete, symmetrical design ensures that the audio signal remains balanced throughout the entire amplification process. By avoiding integrated circuits in the signal path, it achieves lower distortion and a more natural, transparent sound profile.
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$499