The Boston Acoustics CS 26 bookshelf speaker is a member of the company’s well-respected Classic Series of high-fidelity speakers. The line is known for warm yet precise sound reproduction at a reasonable price. While some other top-ranked bookshelf speakers can beat these in terms of pure specifications, none is more desirable in terms of pure musicality. They perform well in a stereo music system and can also serve multiple roles in a home theater system as main or surround sound speakers.
Overall, we found these Boston Acoustics bookshelf loudspeakers to be among the best in this price range and they earned the TopTenREVIEWS Silver Award. Both the Klipsch B-20 and the Infinity Primus P162 scored higher in our ratings as a result of greater sensitivity, but the margin is slim and the Boston Acoustics CS 26s are still rather efficient. The low frequency response for the Infinity bookshelf speakers was also a bit better than these and, despite specifications to the contrary, the Klipsch units seemed to provide a superior treble presence.
The Boston Acoustics CS 26 does a pretty remarkable job of reproducing the full range of musical frequencies, given its diminutive size. While we don’t even expect floor standing speakers to reproduce the lowest tones that people can hear, typically down to 20Hz, we like to see a full-range speaker get as close to being able to play the full range of a bass guitar or standup bass as possible. These don’t quite make it by that standard. Reaching down to a still respectable 52Hz, their lowest tone is equivalent to about a G-sharp, or two-and-a-half notes higher than the elusive low E.
They’re more impressive on the high end, reaching up to an ultrasonic 25kHz. Though 20kHz is generally recognized as the upper limit of human hearing, we can discern ultrasonic overtones. Not actually heard, they contribute markedly to the musical experience by giving a feeling of spaciousness and realism that is missing when speakers can’t reach these heights.
The sensitivity, or efficiency, of a speaker is measured in decibels, dB. The standard measuring technique is to input an electrical test tone with 1W of power and measure the amount of sound, or Sound Pressure Level (SPL), one meter in front of the speaker. At 89dB, the Boston Acoustics CS 26 bookshelf speaker is more sensitive than most of the competition but less so than the two speakers we rated better. This is important because a decrease of just 3dB SPL requires double the amplifier power to achieve the same output. Amplifiers produce much cleaner, more precise sound when they’re not being challenged so much.
It doesn’t take much power to drive the Boston Acoustics CS 26 bookshelf speakers. The manufacturer states that they can be used with as little as 10W of power. On the other hand, they can handle up to a pretty impressive 150W maximum input. That’s quite a lot of power for a small bookshelf speaker, and we suspect that it would be a rare circumstance that that limit would be met.
The Boston Acoustics bookshelf speakers are magnetically shielded, a feature that can be important particularly in home theater applications. A speaker's magnets can cause interference when placed near a CRT television or monitor, and such shielding serves to prevent it. The five-way binding posts allow for great cable connections whether you’re using bare wire, single or dual banana plugs, or spade or pin connectors. They’re also gold plated which, though it likely doesn’t improve the quality of the connection, does tend to minimize the possibility of corrosion.
Like all but a couple of the speakers featured in our reviews of bookshelf speakers, the Boston Acoustics CS 26 includes a single low-frequency driver and a tweeter. The low-frequency driver measures 6.5 inches in diameter and its cone is constructed of a graphite-injected polymer. It incorporates the manufacturer’s Deep Channel Design, which is said to produce more bass response with less amplifier power. While we can’t test the specific claim, we can say that the low-frequency response of this bookshelf speaker is pretty impressive, the comments we made in the performance section of this review notwithstanding.
The high-frequency driver, or tweeter, is a one-inch dome design made of a proprietary material known as Kortec. It’s essentially a slick fabric reinforced with a stiffening agent to make it highly responsive. The soft fabric combined with the reinforced underside seems to be a winning combination because the treble tones are precise and responsive while maintaining a superior, smooth musicality.
These bookshelf speakers are of the bass reflex design, which typically produces more bass than otherwise equivalent acoustic suspension speakers. The design uses pressure produced by the rearward movement of the low-frequency driver to produce additional sound and route it out an external port. It’s typically found that the trade-off for more bass is muddier bass, but we found these speakers to produce sound that is generally clean and appealing.
These bookshelf speakers can be wall mounted and even come with a keyhole mounting bracket. However, we find this type of mounting to be a bit counterproductive given that the bass reflex port is rear-firing. Taking full advantage of this feature requires that there be at least a few inches of open space behind the speaker.
Cosmetically, there are two available finishes. The cherry vinyl appears to be somewhat unnaturally red, but the black ash is comparable to that available on competing products.
Customer support can be contacted by email or telephone during specified business hours. We note that the telephone number is not toll-free. The owner manual is available online and the company’s website includes a FAQs section.
The excellent musicality of the Boston Acoustics CS 26 places them among our favorite entry-level bookshelf speakers. They work well as stereo music speakers and offer an excellent voice match in a home theater with the Boston Acoustics CS 226 that we evaluated in our floor standing speakers review.
These speakers produce exceptional sound that outshines the specifications.
The bass response doesn’t extend as low as we’d like. The cherry finish seems unnatural.
These speakers are an excellent option and well worthy of an audition.