JJ 243 Röhren Stereo Vorverstärker mit Phono-Vorstufe

This is high quality preamplifier intended for customers listening to signal sources with linear outputs and for owners of turntables. JJ 243 has three line and one phono inputs. Selection of the inputs is done by a switch located on the upper panel. Input switching is carried out by top quality signal relays, with an independent relay for every channel. Phono inputs have gain sufficient to connect both, MM and MC pick-ups (from 0,5 mV). The user can select load resistance (10 – 2200 Ohm) for MC inputs and input capacitance (100 - 570 pF) for MM inputs via knobs located on the back panel.

Corrector RIAA is passive. The electrolytic capacitors of JJ Electronic production are bypassed with high quality polypropylene capacitors.

Filament voltages for all tubes are of DC type.

All capacitors in the signal path are of polypropylene type. E88CC tubes of JJ Electronic production, used in JJ 243, showed the lowest level of microphonia among all E88CC brands specially tested for this application. A high quality ALPS potentiometer is used in volume control. JJ 243 has three outputs and their selections depend on user audio equipment. The signal on the first output is amplified and its level is adjustable. The second output signal is not amplified but its level is adjustable. The third output signal is neither amplified nor adjustable, going directly from signal relays of the input switch.

The power source is an integral part of JJ 243, but it is placed on the upper side. Also, the power line transformer is placed inside the shielded box. This design guarantees low interference as of an independent power source.