Soundsmith MMP-3 Phono Preamp

Choosing the Soundsmith MMP-3 Phono Preamp for Your Turntable System

Which cartridges does the Soundsmith MMP-3 phono preamp suit?

Soundsmith MMP-3 phono preamp is designed for medium- and high-output moving magnet cartridges, with a fixed input load of 47k ohms and 100pF. This loading value sets the high-frequency response of a moving magnet cartridge; an input impedance close to a cartridge's specified loading keeps the frequency response within the range the cartridge manufacturer intended, so cartridges calling for standard MM loading won't need separate loading adapters to pair with the MMP-3. Buyers running moving coil cartridges, or cartridges needing non-standard loading values, would need to confirm suitability, since the standard configuration is set for moving magnet operation.

How does the preamp limit noise and preserve signal accuracy?

The MMP-3 is built with ultra-low noise, high-end audio grade components throughout its circuit, which Soundsmith specifies as keeping noise 93dB below the reference signal level. A lower noise floor relative to the signal means quiet passages don't get masked by hiss from the preamp itself, so low-level musical detail stays audible. Total harmonic distortion is rated at 0.004% at 1kHz, indicating the unit adds minimal harmonic artefacts as it applies RIAA equalisation, the standard correction curve that reverses the bass cut and treble boost applied during vinyl mastering.

What gain options does the MMP-3 offer?

Soundsmith MMP-3 is supplied with 43dB of gain as standard, with a 34dB option available to special order, and additional gain and loading values can be specified on request. Gain determines how much the preamp boosts a cartridge's output before it reaches an amplifier's line-level input; lower-output cartridges typically need higher gain to reach a usable signal level, while higher-output cartridges can be overdriven by excess gain. Output clipping is rated at 8.3 volts RMS into 10k ohms, with input overload figures of 5.3mV at 20Hz, 53mV at 1kHz, and 530mV at 20kHz, giving an indication of the headroom available before distortion sets in at different frequencies.

How is the MMP-3 powered, and what does that mean for setup?

The MMP-3 is powered by an external 24V DC supply, available in US 120V or Euro 230V versions. Keeping the power supply external separates the transformer from the audio circuitry, which reduces the chance of mains-related electrical noise reaching the phono stage. Buyers need to confirm the correct regional version at the time of purchase, since the supply is voltage-specific rather than auto-switching.

Will the Soundsmith MMP-3 phono preamp fit a compact system?

Soundsmith MMP-3 phono preamp is 7 inches wide, 4.25 inches deep, and 1.5 inches high, or 2.25 inches including the control knob, and is housed in an aluminium chassis. The metal enclosure shields the internal circuitry from external electrical interference, which matters for a unit handling the very low signal levels a phono cartridge produces before gain and RIAA equalisation are applied. Its dimensions suit placement on a shelf or rack alongside a turntable and amplifier without needing significant extra space.

What configuration options can be specified when ordering?

The MMP-3 is available with a 50 ohm output as an option, alongside the special-order 34dB gain setting and the custom gain and loading values already noted. These options let a buyer match the preamp to a specific cartridge and downstream amplifier combination rather than adapting their system to one fixed specification, which is the main distinction between the standard MMP-3 MKII and a customised build.