Pro-Ject Power Box S3 Phono Power Supply


This item qualifies for our new in-store fulfillment incentive program. Orders over $250 placed online and picked up in-store are now eligible for your choice of a complementary vinyl LP or Burmester Audio CD (up to a $40 retail value) upon pickup. We're excited to welcome you to our showroom!

Experience the power of music with Pro-Ject's Power Box S3 Phono Power Supply! Enjoy efficient, reliable performance from its flexible design. Let your speakers come alive and make your music truly unforgettable.




Power Box S3 Phono is a very efficient and flexible power filter for your turntable and phono preamp. By separating the power supply from the main component, noise and signal contamination are avoided. It is no secret that clean, steady power contributes significantly to the sound quality of audio components.

An Instant Upgrade for Turntables & Phono Preamps
The two outputs are specifically engineered to power Pro-Ject turntables (15V DC only!) and phono preamps (18V). Sophisticated DC filtration allows your turntable & preamp to perform their best. Expect greater speed stability from your turntable and a lower noise floor from your phono preamp, amounting heightened clarity and resolution in analog playback.

In addition to the sonic improvements, Power Box S3 Phono also helps with cable/PSU management by eliminating the need for turntable & phono preamp wall-wart power supplies.



  • PSU upgrade for Pro-Ject phono gear
  • Compatible with all 18V Phono Boxes
  • Compatible with 15V DC turntables*
  • Ultra stable & clean power
  • Low-noise power output
  • Linear voltage regulation
  • Low ESR capacitors
  • Metal enclosure helps block RFI/EMI
  • Available in black or silver
  • Made in Europe
*Not suitable for X8, Xtension 9, Xtension 10, Xtension 12, RPM 5, RPM 9, RPM 10 nor Signature models. For these turntables we recommend Power Box RS2 Phono or Power Box RS Uni TT.




  • Input power supply: 18V / 1000mA
  • Output voltage/ripple: 1 x 15V ±0.5%
  • Output voltage/ripple: 1 x 18V ±0.5%
  • Output current: combined max. 1000mA
  • Dimensions (WxHxD): 103 x 37 x 106mm
  • Dimensions (standard): 4.06 x 1.46 x 4.17″
  • Weight: 370g (0.82 lbs) without power supply


In stock! Usually ships within 24 hours.