Dazzle your ears with KEF's X300A powered speakers

Straight out of England, these small, self-powered speakers serve up big doses of high-end sound.

Steve Guttenberg
Ex-movie theater projectionist Steve Guttenberg has also worked as a high-end audio salesman, and as a record producer. Steve currently reviews audio products for CNET and works as a freelance writer for Stereophile.
Steve Guttenberg
4 min read
KEF's new is a nifty desktop speaker, but it can also be used as a hi-fi or stereo home theater speakers. Granted, it's a bit pricey, but it sounds a lot better than say, a $699 Sonos Playbar. The X300A is a bona-fide high-end speaker system, so it sounds clearer and all around better than all the high-priced sound bars I've heard to date. After all, performance goals for most sound bars are pretty low, they just have to sound better than the iffy speakers built into TVs, and that's easy. Compared with a decent set of stereo speakers, well, that's a very different story.
KEF's handsome X300A Steve Guttenberg/CNET

I'm picking on luxury sound bars as a group, because they all have built-in stereo (and surround) limitations, so I'm suggesting upgrading to stereo speakers. Please don't misunderstand my stance; sound bars can do a reasonable job with movies, where they merely support the main attraction: the picture. With music, sound bars rarely cut it. Don't believe me? Pop on a CD and just listen to a sound bar. Most fall to pieces with music; they're hazy, unfocused, with mushy bass, tizzy highs, and since they're at best only 40 or so inches wide, they can't produce all that much stereo separation. A pair of stereo speakers, spread 60 or more inches apart will sound far more spacious.

The X300As are small bookshelf monitors, 11 inches by 7.1 inches by 9.6 inches, but like most bookshelf speakers, the X300As won't sound right jammed into a bookcase. No, they should be placed on floor stands to be at their best. Build quality is commensurate with high-end expectations, so like all of KEF's high-end speakers the X300A features a Uni-Q driver, and this one bears a strong family resemblance to the driver in KEF's $30,000 Blade flagship speaker. A Uni-Q driver has a tweeter nestled in the acoustic center of the woofer, so all frequencies come from the same point in space. You get more coherent imaging with point source speakers like the X330A than those with their tweeters and woofers separated by a few inches. The X300A's price is pretty high-end, too, they sell for $800 a pair, finished in a gunmetal gray vinyl wrap.

The X300A is a self-powered speaker, but rather than going with the usual generic stereo amplifier stuffed into one speaker, a pair of X300As house four KEF-designed and -manufactured amps. A 50-watt amp drives the 5.25-inch magnesium/aluminum woofer, and there's a separate 20-watt amp for the 1-inch aluminum dome tweeter. KEF's cool-looking "tangerine" waveguide sits in front of the dome to help produce the desired spherical radiation pattern. The X300A weighs 16.5 pounds.

Connectivity options are limited to a 3.5mm analog input, and for desktop duty, a Mini-USB port. The rear panel also has a heat sink, bass port, a small volume control, and a two-position EQ switch that optimizes the sound for free space or wall mounting. The right speaker is similar, but substitutes an L/R balance control for the volume control, and there's a USB input for the cable that connects the two speakers together (the right speaker has its own digital-to-analog converter and amplifiers).

Connectivity issues may hinder the X300A's usefulness as a home theater speaker. You have to hook up the speaker to a TV's stereo variable analog outputs, and many TVs don't have them anymore (the X300A lacks standard optical or coaxial digital inputs). You can hook up the X300A's analog input to a phone, iPod or CD/Blu-ray player; I went for the last option, and used my Oppo BDP-95 player and controlled the speakers' volume from the Oppo. I wasn't happy to discover that the X300A's analog input runs the signal through an internal analog-to-digital converter; I would have preferred that the analog signal remained analog in the speakers, but it does not.

Sound quality was excellent, starting with Eminem's "Live From New York City" DVD, and the X300As bass potency and definition surprised me. Sure, a sub would provide more muscle, but the X300As aren't bad on their own.

Jazz singer/pianist Diana Krall's "Live in Rio" concert DVD demonstrated the smoother side of the X300As' talents. Krall shares the stage with an orchestra, and the speakers' ample richness would put a smile on an audiophile's face. The midrange warmth didn't sacrifice detail, and the spacious soundstage dimensionality was more realistically portrayed than it is with any sound bar that processes stereo to create faux surround sound. The X300A's bass articulation is above par.

Wilco's "Yankee Hotel Foxtrot" CD's dense mixes were easily decoded, and all the little percussive, sparkly bits that run through "I Am Trying To Break Your Heart" came through loud and clear. Stereo imaging was precisely focused, the little speakers disappear as sound sources.

For home theater action trials I played the "Apocalypse Now" Blu-ray over the X300As, and when the helicopters attack a village, the little speakers proved they can played loud, but dynamics are far from what you get from larger speakers. Right; size still matters.

The KEF X300A is a great little speaker, one that's ideal for small rooms. I'm just hoping the next-generation model has direct analog and standard digital inputs.