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In use the DIA-400 is pretty self-explanatory. USB connection of an iPad requires Apple's camera connection kit. Power up from standby takes a few seconds. This is accompanied by a small blinking LED. Once at ready the last selected input goes live with its volume remembered unless it eclipsed 50. In that case it'll start at 50 to not cause heart attacks (which is relative as on 85dB speakers off a 4V source in balanced mode I achieved normal levels at 28). Mute confirms visually with two hyphens instead of volume numbers. Input selection either shuttles sequentially with the fascia control or goes directly to the chosen source via the remote. Display dim via the rear-mounted switch or remote knocks out the dot matrix flat save for two small white LEDs, then reactivates for four seconds with each new prompt. There are no intermediate brightness levels. Like its switching transistors it's either on or off.

The display can be set to either temporarily or permanently display incoming sample rates. In the latter case it replaces the 3-letter source confirmation so OPT becomes 176 for example. When IN1 is set to fixed gain for either home-theater bypass or your own preamp, the volume window displays HT. Again perfectly intuitive as is the following. Should the amp get thermally taxed because it overheats, a HOT warning tells you to shut down. If the display blinks OFF, turn off mains power and check your cable connections. If OFF persists after the next power-up cycle, contact your dealer. That's how comprehensive protection circuitry communicates itself about operational status. Visually neat is how the alphanumeric characters of the display scroll down with a soft transition period like a vertical ticker tape.

Sonic take 0: Fresh outa the box. Coming off the Austrian Crayon high-bandwidth CFA-1.2 with its current-feedback Mosfet outputs and SMPS over the phase/time-optimized Italian Albedo Aptica speakers with down-firing transmission line, the initial sonic impression was of a completely different flavor. The Austrian had been a turbo-charged cobweb-cleaned SET without any triode shortcomings. Think blazingly quick, supremely lit up across the audible bandwidth, ultra specific and with very taut nearly wiry bass of excellent weightiness. The Dane was a rather fatter warmer darker EL34 push-pull amp by contrast. The observer gestalt was concomitantly back not edge of seat. The musical flow was lazier, the tonal balance slightly portly, definition minorly fuzzy. The sound was neither as articulate nor grippy in the bass. Overall resolution had clouded over and with it the completely illuminated spaciousness of the virtual venue. A twitchy Arabian stallion had morphed into a feathered Ardennes draft horse.

As a very first date barely settled down yet, this still confirmed my prior assessment of current-gen ICEpower sound. As perhaps the most widely sold class D platform, it's made a 180% turnabout for the breed (obviously individual implementations can still shift that signature in various ways). Lean, nervous and edgy have become massive, relaxed and soft. A triple espresso has turned latté, a ripped competition-ready bodybuilder has transformed into his beefcake likeness prior to dehydration. Whilst I'm reaching for colorful somewhat exaggerated pointers, this makeover of a ceramic driver 1st-order 2-way of ultra precision into a warmer less keen 3rd-order paper-driver 3-way was very real and not subtle. The things which made the Aptica so very special over the Crayon or Goldmund/Job 225 had changed. The same speaker now sounded a lot more conventional.

Time to let break-in do its thing in the upstairs system driving matchingly white German Physiks HRS-120.

On the full omnis the DIA-400 replaced the Job 225 stereo amp preceded by a shunt-resistor passive with remote. The sonic shift mirrored the first Albedo showing albeit at rather lower magnitude. The Germans deliberately activate the room's ambient field with 360° reflections across the audible bandwidth. This makes them inherently warmer, wetter and less time-specific than direct radiators whose beaming high frequencies act as spot lights on image focus. The flipside is far superior off-axis performance. That's perfect for video. The sound remains anchored on screen for widely spaced listeners. This more diffuse sound was far less critical of the DIA's injected warmth. It didn't change the speakers' inherent character. It simply beefed it up more.
with NuForce-modified Oppo BDP-93 to conveniently run both analog IN1 and digital RCA inputs

Switching by remote between the NuForce-modified Oppo BDP-83's analog and coaxial outputs (Gato's display calls their coax input RCA) netted virtually undetectable transitions. That's because D/A conversion of the DIA-400 was perfectly on par with the custom converter board NuForce had offered for the popular BluRay deck. Unless your eyes were on a valve mod as ModWright offer for the BDP-105 successor, the DIA-400 seems ideal for a stock Oppo universal. No aftermarket mods and extra coin are required to have that perform on an audiophile level. By adding $1.200 to a DIA-250 or DIA-400, you'd have yourself a complete play-anything rig. Just add speakers and wires. Here Gato can help too.