Leben RS-30EQ phono preamplifier

The RS-30EQ has a passive CR (capacitors-resistors) RIAA equalizer. Employs GE (General Electric/USA) 12AT7 tubes authorized by J.A.N. (Joint Army & Navy standard of the US Army).

It reproduces very high quality sound without any NFB (negative feedback). 

To avoid compromising sound quality by not using a typical NFB circuit, one of the solutions adopted to protect the sensitive CR type equalizer was to develop for RS-30EQ a special high quality "Orient-Core" power transformer perfectly shielded to shut-down hum noise from it. Sub-chassis mounting with springs and tube shields has been also adopted against vibration and interference. The finest available components have been selected to keep the deflection of the RIAA curve below +/-0.2%.

It is compatible with 3mV-5mV output cartridges i.e. MM or some High Output MC. For normal MC 0.3mV-0.5mV cartridges the use of an external step up transformer is required. 

   *Gain has been tested at 37dB by "Stereophile" magazine