Music lovers seeking a pair of reference-quality speakers but who are not ready to join the five-figure or six-figure speaker club, KEF has a proposition for you: Check out a pair Reference 1s.

Building on the foundation of KEF’s widely acclaimed LS50 monitor, the Reference 1 ($8000/pair) is a 3-way design featuring KEF’s signature Uni-Q driver. It adds a dedicated 6.5” woofer to the mix as well as a novel feature: A swappable port tube allows users to tune bass response to personal preference and/or room conditions.The show system featured a pair of Parasound JC 1 monoblock amps and a JC 2 stereo preamp. An all solid-state Macbook Pro running JRIVER media center served the digital tunes while a Chord Electronics MoJo DAC converted them into analog.

KEFs demo included a segment where the speakers played for a couple minutes with the longer port tubes in place, followed by the same track using the short ones. It was a sighted test, and I sat through a couple such sessions. When the comparison was complete, Johan Coorg from KEF asked the audience which option they preferred: the short tube or the long tube. The audience was split 50-50 in terms of its preference. There is no correct answer to the question; the longer tube had the effect of improving deep bass response in exchange for a slight reduction in midbass performance.

The two tubes.
I happened to like the sound of the speakers running with the long tube, the extra bass extension more than made up for a slightly more energetic listening experience with the short tube. Johan noted that even when the audience consists of reviewers and other audio press, the split is roughly 50/50.

The port tubes are intriguing as they break several conventions I had come to take for granted. Firstly, they are not rigid. They flex, and are porous. According to KEF that results in reduced chuffing relative to a rigid tube of the same length and diameter. The other unusual design feature is that the tube sits at an angle relative to the enclosure—I’ve asked KEF for more details on the acoustical benefits of that alignment.

Aside from the comparison and focus on ports, the Reference 1 speakers put on a show worthy of their moniker. Within the range they handle—frequency response is 45Hz-35kHz +/- 3dB—the speakers are world-class performers. Typical room gain extends that response down to 30Hz (-6dB). Notably, KEF lists a THD spec of