KEF’s Q Series speakers were introduced in 1991, making them a venerable line. But longevity does not mean the speakers have not evolved. The new 2017 Q Series models represent the eighth iteration of the line. This update, which includes the KEF Q350 ($650/pair), is not merely cosmetic. The company concentrated on improving the fidelity of these favorably priced high-performance speakers with a redesigned port and a damped tweeter-loading tube.
Like KEF’s other lines of loudspeakers, the Q Series lineup features the company’s signature Uni-Q 2-way concentric driver that seamlessly covers a wide slice of the audio spectrum and acts as a point source. The refined design of this driver results in a cohesive, natural soundstage with wide dispersion and great imaging.
Competition among 2-way bookshelf speakers in the Q350’s price range is fierce. If you go looking for great sound, you’ll find it. Does this new model have what it takes to earn a spot in your system? Read on to find out.
Features and Specifications
The Q350 bookshelf is a 2-way speaker featuring a Uni-Q concentric driver with a 1″ aluminum-dome tweeter and a 6.5″ aluminum woofer. Its 14.4″ (high) x 8.27″ (wide) x 12.05″ (deep) ported enclosure weighs 16.8 pounds and is available in black or white.
Check out this unboxing video!
Power handling is spec’d at 120 watts RMS and sensitivity of the speaker is 87 dB (2.83V/1m) with an anechoic frequency response from 63 Hz to 28 kHz (+/-3 dB) and a -6 dB point at 42 Hz. The crossover point is 2.5 kHz and impedance is rated at 8 ohms nominal (3.7 ohms minimum). KEF says you can get up to 110 dB SPL of output per speaker.
On the rear you’ll find the port as well as the speaker terminals, which accept banana plugs. The speakers ship with foam inserts for the ports, allowing you to tune the bass response.
Q350s are sold by the pair and ship without grills. Matching cloth grills are available as an option for $20 each, but in my humble opinion it is a crime to cover up the gorgeous and intriguing-looking Uni-Q driver.
I used an NAD C 368 Hybrid Digital DAC/amplifier to power a pair of Q350s. It’s spec’d at 80 watts per channel (RMS) of load-invariant power. Plus, it has a Bluesound MDC module for easy streaming of Tidal HiFi lossless and Tidal Masters hi-res tracks.
Nearfield measurements revealed a speaker that behaves well and meets its published specs. The frequency response covers a generous range for a speaker of this size and cost, with bass extension that works with room gain to get down to about 35 Hz. On-axis and off-axis frequency response is notably good, surely a result of the sophisticated Uni-Q driver design.
The NAD’s 80-watt RMS output was ample for extracting maximum performance from these speakers. I cranked the volume on some tortuous tracks and pushed the pair hard. The reward was tactile feedback out of hard-hitting dubstep tracks like Excision’s “The Paradox” from The Virus or Datsik’s anthemic “Gravity” from the Sensei EP.
Measurements showed great treble extension and flat response, and in listening the treble possessed great detail that came through without harshness or exaggeration. As long as I avoided tracks with punishing ultra-low bass, the Q350s generated precise and dynamic sound with ease.
The Q350s offer a wide sweet spot in terms of frequency response but getting the full 2-channel stereophonic effect demands that the listener sit centered between two speakers. The reward for doing so is a soundstage that envelops the listener yet is very precise in its rendition of individual objects. Instruments and voices are neither diminished nor exaggerated, resulting in a presentation that mirrors reality.
KEF’s extensive experience in designing and building high-end speakers comes through in the Q350’s ability to realistically reproduce acoustical recordings.
A major highlight of the Q350s is the presentation of vocals. Whether it’s John Lennon, Enya, Bob Marley, Al Jourgensen, Bjork, Elvis, or Lil’ Wayne, there was a verisimilitude to the presentation that qualifies them as Hi-Fi speakers and not merely “good.”
Unsurprisingly, adding a couple of subwoofers to the equation results in deeper as well as more powerful sound overall. I used a pair of KEF R400b subs for this purpose, with Dirac Live and a miniDSP DDRC-88A BM taking care of sub EQ plus bass management. For this review, I did not use Dirac room correction on the Q350 speakers, just the subs. The resulting system response covered 20 Hz to 20,000 Hz with ease, thus qualifying as true full-range sound.
By using an 80 Hz, 24 dB/octave crossover, I was able to play the Q350s at very high levels without distracting distortion or dynamic compression. Compared to a subwoofer, the Uni-Q’s 6.5″ mid/bass cone is excursion-limited at low frequencies. In contrast, at 80 Hz, the speaker produces a lot more sound before that driver runs out of steam.
Combining a pair of Q350s with a sub results in the aural impression of large, powerful speakers playing in the room. And yet, the entire system looks sleek, modern, and compact. It’s hard to imagine anyone encountering much spousal resistance to a speaker system consisting of such attractive components.
Playing “Disc Wars” from the Tron: Legacy soundtrack is a ritual I perform in all my speaker reviews; I plan to do so until the day I die. Without the assistance of the subs, the rendition sounded good at modest levels, but lacked gravitas. Add the subs and the Q350s offer the sort of performance that puts smiles on the faces of audiophiles.
The Q350 offers an affordable option for listeners seeking the sonic advantages of the concentric Uni-Q driver. It’s effectively two speakers in one: When playing full range at modest volume levels, a pair provide an accurate and engaging audiophile listening experience. And when used with a subwoofer and bass management (an 80 Hz crossover works well), they become high-performance satellites that can play loud and clean.
For both 2.0 and 2.1 use, NAD’s C 368 provided all the juice needed to make these puppies sing. They are well-behaved and sound neutral without the need for EQ. If you appreciate speakers that don’t “tint” the sound, you’ll enjoy the Q350s.
While this iteration of the Q350 is new, the Q Series has been around for over two decades. The 2017 update yields a bookshelf that offers contemporary styling plus performance, which bodes well for the rest of the line. If $650 is your sweet spot for a pair of 2-way bookshelf speakers—that make excellent satellites if you add a sub—then, by all means, check out the new KEF Q350.
NAD C 368 Hybrid Digital DAC/Amp with Bluesound MDC module
2X Blue Jeans Cable 10-foot, 10-gauge Belden speaker cable
miniDSP DDRC-88A BM Dirac Live processor
2X KEF R400b subwoofers