TEST BENCH
Analog Performance
All data were obtained from analog test signals applied to unbalanced inputs. Reference input level was 75 mV; reference output is 1 watt into 8 ohms. 1.4v input produced full power.
Output at clipping (1 kHz into 8/4 ohms)
1 channel driven: 364/635 W (25.6/28 dBW)
2 channels driven (8/4 ohms): 315/520 W (25/27.2 dBW)
5 channels driven (8 ohms): 265W* (24.2 dBW)
7 channels driven (8 ohms): 225W*(23.5 dBW)
Distortion at 1 watt (THD+N, 1 kHz)
8/4 ohms: 0.015/0.02%
Distortion at Rated Power (THD+N, 1 kHz)
8/4 ohms: 0.02/0.06%
Noise level (A-wtd): -87.3 dB (dBw)
Frequency response: <10 Hz to 20 kHz +0.2, -0. dB (+3 dB @ 30 kHz; -3 dB @ 60 kHz)
*Estimated results due to test-suite and AC power limits
The Axiom A-1400-8 produced a lot of power, no question about it - enough that I've had to estimate power tests of multiple channels, since with 5 or more channels at clipping the Axiom amp draws all the current my wall circuit can provide when maintaining line voltage at 120vac. (As well, I only have only 7 channels of high-power test-load resistors; every time I get more loads-and these things aren't cheap - they make amps with more channels!) Noise and distortion performance were very good throughout, but I did note an ultrasonic component imposed on clipped waveforms. Moreover, frequency response exhibited a slight rise over the top third-octave or so, continuing to a +3-dB peak at about 30 kHz and rolling off above that point at about 12 dB/octave. -Daniel Kumin
