Audiologica Ltd: Company Registration Number : 6632457    VAT Registration Number: 892 5261 02

Phono Inputs

Input impedance (R and C) MM 47kohms + 200pF

MC 47kohms + 180pF

Input sensitivity MM 0.35mV

MC 5mV

Input overload at 20Hz/1kHz/20kHz MM 0.65/6.5/60 mV

MC 10/100/900mV

Signal/Noise ratio (A-weighted w/ cartridge) MM 78dB A wtd.

MC 76 dB A wtd.

RIAA response accuracy MM,MC +/- 0.3 dB 50Hz-20k

Physical Specification

Dimensions (W×H×D) Imperial 5.3 x 1.38 x 2.75”

Metric 135 x 35 x 70 mm

MC/MM PHONO STAGE

The moving coil preamp is a 4 transistor low distortion amplifier noise-optimised for the very low source impedance of moving coil cartridges. It uses ultra low intrinsic base resistance transistors and operates two of them in parallel push pull for a further 3 dB lowering if input noise. Its input noise is typically 60nV, or 78 dB below 0.5mV (RIAA and A weighted). It has a gain of15 times or 24 dB bringing the lowest output MC cartridges up to MM level. The input impedance is 100 ohms in parallel with 180 pF.

The Moving magnet preamp section uses a low noise low distortion opamp with RIAA equalisation and infrasonic filter in the feedback network. The gain at 1k is 35.2 dB, or 287 mV out for 5mV in with 23 dB overload margin and the frequency response is accurate within +/- 0.3 dB 50Hz-20k, +/- 1 dB 20-50Hz. The infrasonic filter has -3 dB point at 10Hz and is 14 dB down at 5 Hz. The input noise with IHF cartridge source is 0.75uV or 76 dB s/n re 5mV (RIAA and A weighted as per IHF202.)

DIGITAL STAGE

The output of the phono preamp is attenuated, further low pass filtered and fed to the input of the A/D converter. A Soft Clipping circuit is employed to prevent overdriving the A/D converter. The MM preamp has a 100 dB dynamic range and the A/D converter 89dB allowing NAD to optimise the gain for best signal to noise and lowest distortion. The A/D converter has a sampling frequency of 48kHz for USB compatibility and a THD of only 0.01% at 100% FS.

POWER SUPPLY

By increasing the power supply voltage from 15 volts to 24 volts, we have improved overload margins and enhanced musical dynamics. This supply delivers raw DC to the PP-3. Internal circuitry has a precision low noise series current source /shunt regulator arrangement for low impedance and noise. The digital stage is fed by the 5V USB supply of the PC thus offering total isolation of the analogue and digital stages for clean low noise performance.