Integrated Amplifiers

Naim's part-passive/part-active RIAA network has been sensibly judged to offer compatibility with as wide a range of MMs as possible. It offers a +56.8dB gain (an input sensitivity of 1.45mV for 1V preamp output) allied to an input overload of 60mV, or a healthy +24.2dB headroom for an MM offering a 5mV/5cm/sec output. In practice then, this stage has the ideal gain to accommodate high output MCs and enough headroom to avoid clipping with today's beefiest MMs.

The 47kohm/100pF loading is also generic while the stage's LF (rumble/warp) roll-off is slightly less aggressive than the IEC amended curve at –0.6dB/20Hz and –6dB/5Hz [black trace, inset Graph]. Capacitor coupling causes the preamp output impedance to increase from 99ohm/1kHz to 321ohm/20Hz. Distortion is only fractionally higher at LF, from 0.015% (300Hz-20kHz) to 0.03%/20Hz – a commendably flat trend [red infill, inset Graph] that's comfortably superior to any likely partnering pick-up. Finally, noise is low, and the 75dB A-wtd S/N ratio commensurate with the very best turntables. PM