This amp is serious business.
It can output 4kw per channel into 4 ohms. Overall power output is limited to 8kw. This is a lot of power, likely too much for any circuit this amp will ever be on. It will easily trip a 30a breaker if pushed to these levels.
It can burst to about 12.5kw at 20hz, 14kw at 40hz, and 17kw at 80hz and up.
Best THD+N at 8 ohms is about 0.04%, at 4 ohms is 0.08%, and at 2 ohms is 0.18%
Efficiency is excellent, mid 90s into 4.5 ohms.
It is not 2 ohm stable. In fact, an amplifier board let out the magic smoke during sustained high power tests into 4 ohms. The signal in the image below was captured moments before it let go. XBS sent a replacement board. Replacement was trivial and took about 10 minutes. I doubt this is a load the amplifier will ever see in actual use unless playing electronic music at very high levels. That said, the thermal protection was inadequate and did not react quickly enough. There should likely be some intelligent limiting circuitry to prevent this, or components used that can handle the power, but it appears the protection is lacking. This is interesting, since there is some protection for high output at high frequencies. When trying to perform output tests at 10khz and above the amp would go into protect within a second.
Also of note, the heat sinks are not actually copper, but anodized aluminum.
Tests were performed with a 120v unit on a 30a circuit.
This is pushing close to max power at 40hz on a single channel into about 4.6 ohms (voltage scale multiplier is 10x too high and amperage is 10x too low). Output is magenta, power input is purple, voltage input yellow, amperage input blue.
1 channel driven into 4.5 ohms
2 channels driven into 4.5 ohms using separate ps
1 channel bridged into 9 ohms
2 channels bridged into 9 ohms. This gives you a good idea of the maximum output capabilities of the amp.