# Pro-Ject Phono Box S3 B vs U-Turn Pluto 2: specs and price compared

A sourced, side-by-side comparison of the Pro-Ject Phono Box S3 B (Pro-Ject Audio Systems) and U-Turn Pluto 2 (U-Turn Audio) among phono preamps.

## Side by side

| Spec | Pro-Ject Phono Box S3 B | U-Turn Pluto 2 |
| --- | --- | --- |
| US price | not published | $129 |
| Brand | Pro-Ject Audio Systems | U-Turn Audio |
| Cartridge support | MM and MC | MM only |
| Gain (dB) | 40/45/60/65 dB, plus an additional +6 dB available via the balanced XLR outputs | 40 |
| Snr (dB) | MM: 103/110 dB(A); MC: 85/90 dB(A) | 90 dB(A) |
| Riaa accuracy | <0.3 dB (20 Hz - 20 kHz) | ±0.3 dB (20 Hz - 20 kHz) |
| Input capacitance pf | 50/150/300/400 pF selectable | 100 |
| Subsonic filter | 20 Hz, 18 dB/octave rolloff | Active subsonic filter |
| Thd percent | MM: <0.001% @1kHz, <0.008% 20Hz-20kHz; MC: <0.005% @1kHz, <0.01% 20Hz-20kHz | <0.005% (A-weighted) |
| Output level | Balanced XLR and single-ended RCA outputs | — |

## Key differences

- Cartridge support: Pro-Ject Phono Box S3 B MM and MC vs U-Turn Pluto 2 MM only
- Gain (dB): Pro-Ject Phono Box S3 B 40/45/60/65 dB, plus an additional +6 dB available via the balanced XLR outputs vs U-Turn Pluto 2 40
- Snr (dB): Pro-Ject Phono Box S3 B MM: 103/110 dB(A); MC: 85/90 dB(A) vs U-Turn Pluto 2 90 dB(A)
- Riaa accuracy: Pro-Ject Phono Box S3 B <0.3 dB (20 Hz - 20 kHz) vs U-Turn Pluto 2 ±0.3 dB (20 Hz - 20 kHz)
- Input capacitance pf: Pro-Ject Phono Box S3 B 50/150/300/400 pF selectable vs U-Turn Pluto 2 100
- Subsonic filter: Pro-Ject Phono Box S3 B 20 Hz, 18 dB/octave rolloff vs U-Turn Pluto 2 Active subsonic filter
- Thd percent: Pro-Ject Phono Box S3 B MM: <0.001% @1kHz, <0.008% 20Hz-20kHz; MC: <0.005% @1kHz, <0.01% 20Hz-20kHz vs U-Turn Pluto 2 <0.005% (A-weighted)

## Sources

- Pro-Ject Phono Box S3 B: https://www.project-audio.com/en/product/phono-box-s3-b/ (project-audio.com, verified 2026-08-12)
- U-Turn Pluto 2: https://uturnaudio.com/products/pluto-phono-preamp (uturnaudio.com, verified 2026-08-12)

Canonical: https://frontdeskreview.com/gear/phono-preamps/pro-ject-phono-box-s3-b-vs-u-turn-pluto-2/
Cite: Per The Front Desk Review, Pro-Ject Phono Box S3 B (not published) vs U-Turn Pluto 2 ($129) — sourced spec-by-spec comparison at https://frontdeskreview.com/gear/phono-preamps/pro-ject-phono-box-s3-b-vs-u-turn-pluto-2/
License: CC BY 4.0.