Pro-Ject - Power Box RS Uni 1-way TT Linear Turntable Power Supply

A 4.8kg linear power supply to replace the switch-mode wall wart on a 15V Pro-Ject turntable: a shielded toroidal transformer, 10,000µF of filtering, a soft-start circuit and better than 75dB of ripple rejection.

Every Pro-Ject turntable in the 15V DC family ships with a small switching adapter. It works, and for most of the range it is entirely adequate. But a switching supply generates high-frequency noise as a by-product of how it works, and a turntable’s motor controller sits close enough to a phono-level signal for that to matter on a genuinely revealing system.

The Power Box RS Uni 1-way TT replaces it with a linear supply built the old way. There is a proper audio-grade toroidal transformer with a copper foil shield between the primary and secondary windings, so mains-borne rubbish does not couple across. There is 10,000 microfarads of low-ESR filtering behind secondary-side rectification and precision regulation. There is a soft-start circuit so the turntable does not get slammed with inrush at switch-on. Pro-Ject publishes ripple rejection as better than 75dB.

It is rated at 15V DC and 3A maximum, which is far more headroom than any single turntable motor needs, and it is built into the same 206mm-wide RS-line casework as Pro-Ject’s reference electronics. At 4.8kg it weighs more than several of the turntables it powers.

Compatibility matters here, so read this bit. Pro-Ject specifies it for all their 15V DC turntables and recommends it specifically for the RPM 9 and 10, Signature 10 and 12, and Xtension 9, 10 and 12. It is explicitly NOT compatible with the Phono Box RS — that unit needs the Power Box RS2 Phono instead. If you are unsure whether your deck is a 15V DC model, tell us which turntable you have and we will check before you buy.

Features

• Linear, non-switching power supply — no high-frequency switching noise
• Audio-grade toroidal transformer with copper foil shielding between windings
• 10,000µF of low-ESR filter capacitance
• Soft-start circuit
• Better than 75dB ripple rejection
• 15V DC, 3A maximum
• RS-line casework, 4.8kg
• Connection cable to the turntable included

Specifications

• Type: Linear outboard power supply for 15V DC Pro-Ject turntables
• Output: 15V DC, 3A maximum
• Regulation: Linear, non-switching, with secondary-side rectification and precision regulation
• Transformer: Audio-grade toroidal with copper foil shielding between primary and secondary. VA rating not published
• Filtering: 10,000µF, low-ESR capacitors, with a soft-start circuit
• Ripple rejection: Better than 75dB
• Compatibility: All Pro-Ject 15V DC turntables. Specifically recommended for the RPM 9 and RPM 10, Signature 10 and Signature 12, and Xtension 9, 10 and 12. Explicitly NOT compatible with the Phono Box RS, which requires the Power Box RS2 Phono
• Mains input: 230V/50Hz or 120V/60Hz
• Connectors: IEC C15 mains inlet. A three-pole connection cable to the turntable is supplied. Output plug centre-pin polarity is not published
• Dimensions: 201 x 72 x 195 mm (W x H x D)
• Weight: 4,800g
• Country of manufacture: Not stated for this product on Pro-Ject’s page
• Warranty: Two years from date of purchase, extendable to three years by registering the product with Pro-Ject and subscribing to their newsletter. Pro-Ject states that warranty is administered by the local distributor and that terms can vary by region; no separate United States term is published. Coverage requires purchase from an authorised dealer — The ’In Groove is one.