The LS6 is a cherry finished, rear-ported, 17 litre two-way standmount design, featuring a long-throw 165mm polypropylene mid/bass cone unit, coupled with a 19mm dome tweeter. That port is a big-un, and vents to the top half of the rear panel, with a single set of gold-plated speaker terminals at the lower half. There is a three-way switch on the front panel that allows a +1dB and +2dB treble lift, to accommodate for well-damped rooms or off-axis listening. This is next to the tweeter behind the grille, which is designed to be kept in place throughout listening (if you remove it, the lip surrounding the front baffle does give a noticeable baffle-step notch in the response).
The 165mm mid/bass unit is the perfect combination for a BBC-type loudspeaker in a world that has, somewhat regrettably in many opinions, moved on from Radio Three and a steady diet of classical music. It’s in the Goldilocks spot between the ‘taut but light’ output of the smaller driver on the LS3/5 and the ‘big but relaxed’ sound from the larger unit on the LS5/9.
The loudspeaker is a perfect partner for the H80, being rated at a somewhat below average 87dB sensitivity, but with an easy nominal eight ohm impedance. It is recommended to be used with amps from 50W-150W and the H80 fits perfectly in the middle of that range. The loudspeakers are designed to play at 100dB and beyond fairly comfortably with an amp of the H80s size. In a typical mid-sized 12’ x 16’ UK living room, this is more than loud enough to be uncomfortable, although if you are a true party animal who feels good sound only exists at the threshold of pain, other loudspeakers (and regular hearing tests) are recommended.
The traditional wadding within a BBC loudspeaker was Dr. Bailey’s Long-Haired Wool, but Rockwool has replaced that here. Sadly ‘Dr. Bailey’s’ is no longer in existence, and the alternatives are either impractical or not sonically superior to Rockwool.
With such a large rear port, the LS6 does require a lot of space between it and the back wall. It’s not the kind of loudspeaker that fits the term ‘bookshelf’ anyway, but if it can be at least a metre from the rear wall, that should be a good start, In fact, the closer it gets to 1.3m or more, the better. This is somewhat at odds with other designs in the Graham and Chartwell lines, which are either sealed box or front-firing designs and therefore can work reasonably close to the wall. Depending on your seating position, they work best on stands between 450mm and 550mm high, but can work well with 600mm stands, too. Fortunately, weighing in at 9.5kg each, and with a relatively low centre of gravity, the LS6 is not a stand-crushing weight. The choice of stand material doesn’t appear that important, although resting on lower mass stands seem more in line with the LS6 bass than being bonded to high-mass models. The latter, in extremis, can seem to add too much of a legato bloom over the bass and upper bass.
Careful installation is handy, but not to the point of obsession. Get them level, toed in, and in approximately the right position and the system will sound good. Spend two more days tweaking them until they are in the perfect position and they will sound ever so slightly better. This is a loudspeaker that works well with an installation that owes more to measuring the room and trigonometry, than it does to magic spells, numerology, and ley lines.