Audioengine's spectacularly good A2 has been my powered speaker reference for years. I recently enthused about Audioengine's slightly larger passive P4 speaker ($249/pair) that need to be powered by a separate amp. I was surprised that Audioengine didn't introduce an amp when they brought out the P4, but now with the N22 ($199), the time has come.
It's an unobtrusive, vertically oriented design--7 inches high, 2.75 inches wide, and 5.5 inches deep--and it weighs 3.5 pounds. The clean front panel has just a volume control and a 3.5mm headphone jack; the rear end has stereo RCA inputs and subwoofer outputs; metal speaker wire binding posts; and a USB port for charging portable devices. The N22 accepts analog signals only. The medium-density fiberboard wood cabinet is finished in satin black, and the amp has a separate power supply.
The digital amp puts out 22 watts per channel; that's about right for the P4 speakers. The sound was nowhere as warm and sweet as the A2, but it was considerably more detailed and lively. At first I missed the A2s easygoing nature, but I quickly came to appreciate the N22/P4's superior resolution, dynamic drive, and improved bass definition.
The P4's bass is fine, but its 4-inch Kevlar cone woofers aren't exactly the last word in punch or power. So I hooked up my PSB Alpha B speakers, and its 5.25-inch woofers uncorked a more satisfying low-end experience. But the 11-inch-high PSBs are a little too big for my desktop, so I brought the P4s back. I thought I'd never retire the A2s, but now that I've grown accustomed to the N22/P4's detail and clarity, there's no going back. It's a winning combination, but I'm sure most small speakers would be fine with the N22.
I plugged a pair of Sennheiser HD-598 headphones (review to come) into the N22, and came away pretty impressed by what I heard. The sound was extremely open and pure, so the N22's headphone sound is another reason to consider this little amp. The N22's headphone amp is decent enough, but the Schiit Audio Asgard dedicated headphone amp ($249) was noticeably more transparent-sounding.
You can purchase the N22 direct from Audioengine's online store, and the $199 price includes FedEx delivery. The amp is sold with a 30-day return guarantee.