Since the A2+'s most significant upgrade from the original A2 is its built-in USB digital converter, we started listening to the A2+ on a desktop, hooked up to our Mac Mini computer. The sound was definitely up to audiophile standards, just on a smaller scale than what we'd hear from a bona fide hi-fi system. Seated just a few feet away from the speakers the sound will be familiar to anyone who has heard the original A2 speakers. It's well-balanced, clear and refined, but the sound isn't going to fool anybody into thinking the A2+ is a big, powerful speaker. It sounds reasonably full, but if you crave deep bass, plan on either adding a subwoofer or go for bigger speakers, like the Audioengine A5+s. Placement near a wall will help the little A2+s maximize their bass response; move them more than a few feet away and bass fullness thins out.
Seeing how the A2+'s digital converter is the biggest change from the A2 (it only had analog inputs), we alternated between listening via the A2+'s USB input and analog RCA connections, the latter were hooked up to the A2+s straight from the Mac Mini's analog (headphone) output jack. There was some small loss of bass oomph, detail and texture in the sound from the analog connection, and the stereo soundstage forfeited some dimensionality. If you're using the A2+s with a computer we definitely recommend using the USB input.
We also ran the A2+s with a TV, using the TV's stereo analog outputs. These are very small speakers, but in a small room the A2+s can be used instead of a sound bar. Movies and music sounded quite good, as long as we didn't try to play the speakers very loud. In any case the A2+s will produce a sizable upgrade in sound quality over the TV's speakers. Comparing the original A2 with the A2+ (with the analog connections) the two models sounded virtually the same. Then again, if you plan on using the A2+ with a computer's USB connection there will be a small improvement in sound quality with the new speaker.
Like with the original A2s, we have no problem recommending the plus version of the product. If you're looking for a set of compact, good-looking PC speakers that deliver great sound for their size, the Audioengine A2+ certainly fits the bill. The larger Audioengine 5 series delivers a richer, fuller experience, but for many, the step-up model will just seem too bulky to leave sitting on a desk (they truly are bookshelf speakers with a more industrial, monitor flair to them).
In terms of competitors, there are plenty of other swanky multimedia speakers out there, several of which we haven't reviewed. One set we did review, the Bowers & Wilkins MM-1, looks great but the A2+ sounds better and costs half the price.
Other competitors incorporate Bluetooth connections. The $300 Harman Kardon Nova 2s are a slick set of speakers that's also smartphone- and tablet-friendly. And then there's more modestly priced , a good value at around $100 online. The Z600s also feature a Bluetooth connection.
I wouldn't call the Audioengine A2+ a steal at $249.99, but it seems fairly priced. The big question is whether it's worth spending the extra $50 for the enhancements the newer model offers (the A2 remains on the market at $199.99). As we said, you don't get a significant bump in sound quality when moving to the A2+, but it does make a small difference when you connect the speakers via USB. I think I'd probably spend the extra $50 on the newer model, but I tend to go with the latest and greatest so long as I don't have to pay too much of a premium to do it. But not everybody feels the same way.
Editors' note: Steve Guttenberg, who writes CNET's Audiophiliac blog, contributed to this review.