# Pro-Ject Phono Box S3 B vs Parasound Zphono: specs and price compared

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

## Side by side

| Spec | Pro-Ject Phono Box S3 B | Parasound Zphono |
| --- | --- | --- |
| US price | not published | $200 |
| Brand | Pro-Ject Audio Systems | Parasound |
| Cartridge support | MM and MC | MM and MC, switchable gain |
| Gain (dB) | 40/45/60/65 dB, plus an additional +6 dB available via the balanced XLR outputs | MM: 46 dB; MC: 61 dB @ 1 kHz |
| Snr (dB) | MM: 103/110 dB(A); MC: 85/90 dB(A) | MM: 84 dB; MC: 58 dB |
| Riaa accuracy | <0.3 dB (20 Hz - 20 kHz) | ±0.25 dB (20 Hz - 20 kHz) |
| Input capacitance pf | 50/150/300/400 pF selectable | 150 |
| Subsonic filter | 20 Hz, 18 dB/octave rolloff | — |
| Thd percent | MM: <0.001% @1kHz, <0.008% 20Hz-20kHz; MC: <0.005% @1kHz, <0.01% 20Hz-20kHz | — |
| Output level | Balanced XLR and single-ended RCA outputs | 1.1 V |

## Key differences

- Cartridge support: Pro-Ject Phono Box S3 B MM and MC vs Parasound Zphono MM and MC, switchable gain
- 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 Parasound Zphono MM: 46 dB; MC: 61 dB @ 1 kHz
- Snr (dB): Pro-Ject Phono Box S3 B MM: 103/110 dB(A); MC: 85/90 dB(A) vs Parasound Zphono MM: 84 dB; MC: 58 dB
- Riaa accuracy: Pro-Ject Phono Box S3 B <0.3 dB (20 Hz - 20 kHz) vs Parasound Zphono ±0.25 dB (20 Hz - 20 kHz)
- Input capacitance pf: Pro-Ject Phono Box S3 B 50/150/300/400 pF selectable vs Parasound Zphono 150
- Output level: Pro-Ject Phono Box S3 B Balanced XLR and single-ended RCA outputs vs Parasound Zphono 1.1 V

## 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)
- Parasound Zphono: https://www.parasound.com/products/zc-zphono (parasound.com, verified 2026-08-12)

Canonical: https://frontdeskreview.com/gear/phono-preamps/pro-ject-phono-box-s3-b-vs-parasound-zphono/
Cite: Per The Front Desk Review, Pro-Ject Phono Box S3 B (not published) vs Parasound Zphono ($200) — sourced spec-by-spec comparison at https://frontdeskreview.com/gear/phono-preamps/pro-ject-phono-box-s3-b-vs-parasound-zphono/
License: CC BY 4.0.