Soundsmith MMP-4 Phono Preamp

Soundsmith MMP4 Phono Preamp

What Makes the Soundsmith MMP4 Different from Other Phono Preamps?

The Soundsmith MMP4 Phono Preamp is built around the same circuit philosophy as Soundsmith's higher-specified MMP3, giving buyers access to a design lineage rather than a standalone budget unit. Soundsmith uses the MMP4 and MMP3 to demonstrate its cartridges at hi-fi shows, including its high-end cartridge designs, which indicates the preamp is treated as a genuine reference tool rather than an entry-level afterthought. The MMP4 and MMP3 have been demonstrated against preamps costing between two and four thousand US dollars, with Soundsmith reporting favourable results in those comparisons. High grade low noise components keep the unweighted noise floor at 92dB down, which is the practical reason a buyer hears a quieter background and more low-level detail from records rather than circuit hiss.

Which Cartridges Work with the MMP4 Phono Preamp?

The Soundsmith MMP4 Phono Preamp is designed for high output moving magnet, moving coil and Soundsmith's own MI (moving iron) cartridges, rather than low output moving coil designs that need a separate step-up stage. It loads a cartridge at 47k ohms with 100pF of capacitance, matching the standard impedance and capacitance window that most MM and MI cartridges are designed around, so a buyer can pair the MMP4 with their existing cartridge without needing to source custom loading components. Gain is set at 43dB as standard, with a 34dB option available to special order, allowing the preamp to suit cartridges with differing output levels and giving owners a route to optimise headroom and gain staging for their specific cartridge rather than accepting a single fixed setting. Buyers running a low output moving coil cartridge instead would need a step-up device, such as Soundsmith's MCP2, which uses fully shielded internal transformer step-ups and a continuously variable loading range from 10 ohms to 5k rather than the fixed loading of the MMP4.

How Do You Set Up the MMP4?

Setup is described as straightforward, with the MMP4 supplied with easy to follow instructions and powered by an external DC power supply rather than an internal mains transformer. Keeping the power supply external moves a potential source of electrical noise and heat away from the audio circuit board, which supports the low noise figures the preamp is built to achieve. The unit ships ready to wire into a turntable and amplifier or preamplifier's line-level input, so an owner is not required to make internal adjustments to access the standard 43dB gain and 47k/100pF loading.

Who Is This Preamp Suited To?

The Soundsmith MMP4 suits a vinyl listener who already owns, or plans to buy, a high output MM, MI or MC cartridge and wants a dedicated phono stage rather than a built-in phono input on an amplifier. It's positioned for owners who want measurable performance gains, in the form of low noise and accurate RIAA equalisation, without moving up to step-up transformer-based moving coil preamps such as the MCP2 or MCP3, which are aimed at low output moving coil cartridges and carry a different setup and loading process as a result.

How Is the Soundsmith MMP4 Built?

Each MMP4 circuit is hand-made and housed in a high quality aluminium case, which gives the preamp a degree of electrical shielding and physical durability while keeping it compact enough to sit alongside a turntable or in a equipment rack. The circuit is built to deliver an extremely accurate RIAA equalisation response, the standard curve that vinyl records are cut to, so playback frequency balance matches the mastering engineer's original intent rather than drifting at the frequency extremes. Combined with the external DC power supply and high grade low noise components used throughout the circuit, the construction is aimed at consistent, repeatable performance for owners who intend to keep the preamp as a long-term part of an analogue system.