Audio Refinement Pre-2DSP & Multi-5 preamplifier-processor & multichannel power amplifier Measurements
The Multi-5's frequency response measured –0.58dB at 10Hz, –0.17dB at 20Hz, –0.03dB at 20kHz, and –0.19dB at 50kHz. The amplifier's gain measured 32dB with its level controls set to maximum. The signal/noise ratio at 1W into 8ohms measured –108dB, A-weighted. THD+noise at 1W into 8ohms measured 0.004% at 20Hz, 1kHz, and 20kHz. The THD+N at 2W into 4ohms was 0.004% at 20Hz, 0.005% at 1kHz, and 0.006% at 20kHz.
With all five channels driven, the Multi-5 clipped (1% THD+N) at 176W per channel at 20Hz, and at 180Wpc at 1kHz (194Wpc with two channels driven at 1kHz into 8ohms). Into a 4ohms load, five channels driven, the amp clipped at 228Wpc at 20Hz and at 238Wpc at 1kHz (297Wpc with two channels driven at 1kHz into 8ohms).
The Multi-5's power output is clearly more limited into 4ohms loads than that of physically beefier amps with the same 8ohms power output, but it still clearly exceeded its specifications.—Thomas J. Norton