WarmGain Step-Up

Description

The WarmGain Step-Up Transformer is a passive device that provides transformer gain before the MM input of any phono preamp — specifically for use with very low-output moving-coil cartridges whose output voltage falls below the noise floor of a standard MM phono stage. A step-up transformer provides this gain through electromagnetic induction rather than active amplification, which means it adds zero noise of its own. The gain comes from the turns ratio of the primary and secondary windings; the signal is transferred without entering any active component.

Why a Step-Up Transformer Rather Than an MC Phono Stage

An active MC phono stage applies gain through transistors or operational amplifiers — which introduce their own noise, even at very low levels. At the signal voltages produced by a low-output MC cartridge (0.1-0.3 mV), even well-designed active stages have a noise floor that limits dynamic range. A step-up transformer transfers the signal without any active component:

– Permalloy core winding — higher permeability than standard silicon steel, lower hysteresis distortion at audio frequencies
– Mumetal external shielding can — prevents electromagnetic interference from nearby mains transformers and motor fields
– Available in 1:10 winding ratio — provides 20 dB of transformer gain, suitable for cartridges outputting 0.2–0.5 mV
– Available in 1:20 winding ratio — provides 26 dB of gain, suitable for cartridges outputting below 0.2 mV
– RCA input and output — connects between the cartridge leads and the MM input of any phono preamp

Selecting the Correct Turns Ratio

The correct turns ratio depends on the cartridge output voltage and the MM gain of the phono preamp:

– Cartridge output 0.2–0.5 mV + standard 40 dB MM phono preamp: use 1:10
– Cartridge output below 0.2 mV + standard 40 dB MM phono preamp: use 1:20

Backed by a two-year warranty.