The 333A Distortion Analyzer measures total distortion down to 0.1% between 5Hz and 600kHz; harmonics up to 3MHz. Measures noise as low as 50 µV, voltage from 300 µV to 300 V full scale. Automatic nulling mode and high-pass filter: 3 dB point at 400Hz with 18 dB per octave roll off; 60 Hz rejection: 40 dB.