At $2,500, the KAV-400xi is not an inexpensive piece, yet it offers great audiophile value. Your money buys you 200 watts per channel of real Krell amplification. This means a low negative feedback design, fully balanced signal path and pure class-A circuitry up to the driver stage. In addition to this, you also get a full-featured line-level preamplifier.  The preamplifier will even let you configure one of the inputs to a Theater Throughput mode, which bypasses the internal volume and balance control, so that the KAV-400xi can be used to drive the front pair of speakers in a home theater system.

The entire chassis is machined out of thick aluminum panels and built like a tank. The panels feature a brushed anodized finish, with the corners made out of separate pieces of highly polished and rounded metal. The front panel features, from left to right, a power button with an indicator light that glows the familiar Krell blue when on and red when in standby, four source selector buttons, tape, mute, an LED display for volume and balance and, finally, a knob for volume control.

The rear panel features a detachable power cord, four single-ended inputs (one marked tape), one balanced input, tape and pre-amp single-ended outputs, five-way binding posts, an RC-5 input and a 12-volt trigger input and output.

The 400xi, like its predecessor, comes with a thin, credit card-sized remote. The buttons are slightly raised and made out of some sort of plastic membrane material. I personally don't mind the remote's design, as it fits with the 400xi's contemporary aesthetic, but I have heard complaints about it. Admittedly, this design does not work well in darkened rooms, as it is not backlit and the buttons are hard to distinguish by feel alone.

The performance capabilities of the KAV-400xi are extremely good. Despite its small form factor, roughly 17 inches square and less than four inches high, it packs a wallop. The amplifier never ran out of steam or lost control. Sound quality was neutral and refined, without the glare and grain that plague so many solid state designs. This is an integrated amplifier that offers true audiophile performance.