The Adcom GFA-7607's frequency response measured –0.16dB at 10Hz, –0.04dB at 20Hz, –0.16dB at 20kHz, and –1.00dB at 50kHz. The amplifier's gain measured 28.9dB, and its A-weighted signal/ noise ratio at 1W into 8ohms measured –116dB. The THD+noise at 1W into 8ohms was 0.002% at 20Hz, 0.005% at 1kHz, and 0.005% at 20kHz. THD+noise at 2W into 4ohms measured 0.010% at 20Hz, 0.009% at 1kHz, and 0.004% at 20kHz.

Into an 8ohms load with all seven channels operating, the GFA-7607 clipped (1% THD+noise) at 136W per channel at 20Hz and 140Wpc at 1kHz. Into 4ohms, six channels driven (our bench-test resistor bank is limited to six channels at 4ohms), clipping occurred at 224Wpc at 20Hz and 230Wpc at 1kHz. With only two channels driven at 1kHz, the GFA-7607 clipped at 168Wpc into 8ohms and 301Wpc into 4ohms.—Thomas J. Norton