The Evolution 400e amplifier is the lowest powered monaural amplifier in the Evolution Series. With a robust 400 watt output into 8 Ohms, this baby brother delivers plenty of punch. Potent enough for almost any application, the Evolution 400 shares the same sophisticated circuit topologies as its larger siblings but packs it into a smaller chassis. The Evolution 400e is perfect for when high performance is critical but space is at a premium. The Evolution 400 is equipped with a massive 4,000 VA transformer. This power source is the backbone for the output of the Evolution 400. With this foundation, the Evolution 400e delivers 400 watts into 8 Ohms, 800 watts into 4 Ohms, and 1,600 watts into 2 Ohms. The FTC mandates that power ratings are quoted using a 1000 Hz sine wave into a fixed 8 Ohm resistor with final power specification stated at 1% distortion. Krell engineering considers this specification too lenient and not indicative of what an amplifier is required to provide. Krell designs to a much stricter standard. Our power tests use a 20-20,000Hz signal into 8, 4, and 2 Ohm loads with our final specifications stated for .1% distortion. Krell Active Cascode Topology offers several performance advantages. It breaks through bandwidth limitations of conventional designs and delivers very high current. The usable bandwidth of an Evolution 900 is 300 MHz; triple the bandwidth of a typical high performance amplifier. The result is near perfect performance in the audible range with no phase anomalies typical of lower bandwidth designs. Evolution amplifiers feature Krell CAST technology. CAST is a unique circuit and connection breakthrough that eliminates distortions inherent in voltage based amplification. A complete Evolution (source, preamplifier, and amplifier) system, connected with CAST interconnects reduces the number of voltage gain stages to the minimum, one. The resulting noise floor is approaching the theoretical limit of technology.