Pro-Ject Accu Box S2 Battery Power Supply - Silver

What You Need to Know

Off the Grid, Out of the Noise

The quietest power supply is no power supply at all. The Accu Box S2 runs your phono electronics on pure battery power—five cells of rechargeable Li-Pol batteries with a 2.6Ah capacity—so hum, RFI, and mains-borne interference simply never enter the signal. With a delicate phono signal, the difference is immediate: a more homogeneous, spacious sound with better separation, imaging, and a cleaned-up, relaxed presentation.

Built-in over-charge, over-discharge, and over-current protection safeguards the batteries for maximum lifespan. A full charge takes about three hours and delivers roughly 6.5 hours of playback.

Two Outputs, One Compact Box

The Accu Box S2 provides an 18V/1A output (2.5mm) for Pro-Ject phono preamps and electronics, plus a 5V/1A USB A output for components like the Pre Box S2 Digital, DAC Box S2 +, and Head Box S2. A front-panel push button enables or disables both rear outputs, with an LED confirming status.

Solid, Simple, System-Friendly

Housed in full aluminum/metal casework just 4 inches wide, the Accu Box S2 tucks in anywhere. Choose black or silver to match your Pro-Ject stack.

Features & Specifications

True Battery Power — Five Li-Pol cells (2.6Ah)—zero mains noise reaches your electronics.

Full Battery Protection — Over-charge, over-discharge, and over-current safeguards for maximum battery life.

Dual Outputs — 18V/1A (2.5mm) for phono electronics; 5V/1A (USB A) for DACs, headphone amps, and more.

Front-Panel Control — Push button enables/disables outputs; LED indicates status and charging.

Audiophile Build — Full aluminum/metal casework in black or silver.

Specifications

• Type: Rechargeable Battery Power Supply
• Battery: 5-Cell Li-Pol, 2600mAh
• Output 1: 18V DC / 1A (2.5mm)
• Output 2: 5V DC / 1A (USB A)
• Playback Time: Approx. 6.5 Hours
• Charging Time: Approx. 3 Hours (outputs disabled)
• Charger: 21V (included)
• Compatibility: Most Pro-Ject Phono Box, S2, S3, E, and DS-Line Electronics (see FAQ)
• Dimensions: 4.0"W x 1.4"H x 4.2"D
• Weight: 1.2 lbs
• Finish: Black or Silver

Frequently Asked Questions

Which components can it power?

Pro-Ject lists the following as compatible. S-Line: Stream Box S2, Stream Box S2 Ultra, BT Box S2, Pre Box S2 Digital, Pre Box S2 Analogue, DAC Box S2 +, Head Box S2, Head Box S2 Digital, Tube Box S2, Phono Box S2, Phono Box S2 Ultra, Phono Box S3 B, and Vinyl NRS Box S3. E-Line: Optical Box E, Phono Box E, Phono Box E BT, and Record Box E. DS-Line: Phono Box DS2, Phono Box DS2 USB, Tube Box DS2, Tube Box DS3 B, Phono Box DS3 B, DAC Box DS2 Ultra, Pre Box DS2 Digital, Pre Box DS2 Analogue, Head Box DS2 B, and CD Box DS3. Ask us about your specific components.

Can it power my Pro-Ject turntable?

Yes, with the optional Pro-Ject Connect-It 18V/15V 2.5-2.1mm cable (sold separately), the Accu Box S2 can power most Pro-Ject turntables as well.

What difference will I hear?

A phono signal is tiny, so any power supply noise ends up in the music. Battery power removes the AC mains from the equation entirely—revealing quieter backgrounds, better separation and imaging, and a more spacious, natural sound.

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