Mark Levinson No.334 power amplifier Measurements page 2
Fig.3 Mark Levinson No.334, THD+noise (%) vs frequency at (from top to bottom at 10kHz): 4W into 2 ohms, 2W into 4 ohms, 1W into 8 ohms, and 2.83V into simulated loudspeaker load (right channel dashed).
Fig.4 Mark Levinson No.334, 1kHz waveform at 40W into 4 ohms (top), distortion and noise waveform with fundamental notched out (bottom, not to scale).
The distortion spectrum resulting from a 50Hz input at 167.5W into 4 ohms is shown in fig.5. All artifacts are below -80dB (0.01%), an excellent result. Fig.6 shows the 19+20kHz intermodulation spectrum at 67.7W into 4 ohms. (Visible signs of clipping start to appear at higher levels with this signal.) The highest-level artifact is -72dB (about 0.025%) at 18kHz. At 125.5W into 4 ohms (not shown), the IM distortion is lower: a maximum of -77.3dB (about 0.014%) at 18kHz.
Fig.5 Mark Levinson No.334, spectrum of 50Hz sinewave, DC-1kHz, at 167.5W into 4 ohms (linear frequency scale).
Fig.6 Mark Levinson No.334, HF intermodulation spectrum, DC-22kHz, 19+20kHz at 67.7W into 8 ohms (linear frequency scale).