
The Focal XS Book is a two unit powered speaker with relatively compact dimensions (11” high x 4.5” wide x 7.9” deep). While aimed at the desktop market, where each speaker would normally be placed to the sides of a computer monitor, it’s compact dimensions and neat wiring also lend the XS Book to other uses. For example, you could simply use it with an iPhone, Android or iPod as a basic music system. You could also hook it up to the analog output of a television to improve the audio. We tested it primarily as a computer audio speaker in desktop, near field mode (about 2.5’ from speaker to listener), though we also tried it from farther away as you would use the speakers in the secondary applications just described.
The XS Book has a 4-inch mid/bass driver in a ported enclosure, crossed over at 3000 Hz to a 0.8-inch tweeter. The amplifiers are housed in the right speaker enclosure, which is also where the power cord and low level input are connected. The left channel signal from the amplifier is fed to the left speaker via a one-meter connecting cable from the right speaker. The XS Book has analog inputs only, accepting either a stereo mini-plug or L/R RCA inputs. A volume control is embedded on the top of the right speaker; there is no remote control offered.
Consider these speakers if:
• You want a consistently listenable and enjoyable sound from a small, well-made desktop speaker.
• You want a desktop speaker that conveys ample detail yet is free from the stridency, harshness, or midrange glare that undermine the performance of some competing desktop speakers.
Look further if:
• You require a speaker that can produce deep, punchy bass (the XS Book does well for its size, but it does have its limits).
Ratings (relative to comparably priced active speakers):
• Tonal Balance: 9.0
• Smoothness: 9.0
• Frequency Extremes: 8.0
• Clarity: 8.5
• Soundstaging: 8.5
• Dynamics: 8.5
• Value: 9.0

The impressive aspect of the XS Book is how well it conveys the detail and energy of a recording while at the same time managing to avoid a harsh or edgy sound. Many small speakers, especially speakers designed for both desktop and in-room use, have a sharpness on transients that is somewhere between distracting and painful. But the XS Book exhibits admirable smoothness through the upper midrange region, which allows the music to flow naturally. We don’t know if this is due to superior drivers (Focal is one of the largest manufacturers of high-performance drivers in the world) or more careful crossover design, or attention to the details of desktop usage. But whatever the reason, the XS Book neatly avoids a problem we’ve experienced with a high percentage of small, desktop speakers we’ve heard in the past.
While we might seem to be focusing on a relatively small aspect of performance, we emphasize this quality of smoothness because it is more important to naturalness and musical enjoyment, in our view, than one might think. We also mention it because, while the XS Book does have some readily observable performance shortcomings (as one would expect of a product at this price point), its overarching smoothness and sonic subtlety enable it to provide a great deal of musical satisfaction in spite of any deficiencies.
What kinds of shortcomings are we talking about? In simple terms, we would say that the XS Book exhibits a series of small, subtractive distortions. Subtractive distortions are those that involve the speaker not doing something desirable (or at least not doing it as fully as one might wish). Often you don’t notice these sorts of subtractive errors nearly as much as you would additive distortions. Additive distortions are more in your face, and thus more noticeable and distracting (a good example would be the upper midrange glare we’ve encountered so often with other small desktop speakers).
Let me provide a few practical examples to illustrate ways in which the XS Book transcends subtractive distortion.
The XS Book doesn’t deliver much bass below 50 Hz, which you might think would be a serious omission, but in practice it is not. You sense a certain lack of very low-frequency information in the overall balance of the speakers, but you have to think about it a bit because the speaker doesn’t thrust this problem at you. On the contrary, the bass that is present mostly sounds right, while the missing low bass frequencies rarely seem conspicuous (although we think some listeners might think about adding a subwoofer to complement the XS Book’s low-end output).