Construction is glued mdf with veneer over the top, available in black or beech. The beech finish seems to go darker and yellower with sunlight exposure so on my 20 year old example behind the grills is lighter, likewise if you take the outriggers off the underlying veneer is lighter underneath but none of it has pealed. The black finish may be better.
The drivers are mounted in a solid aluminium frame stamped 'Coda', there is a rod screwed into the frame that passes through the back and pulls the frame tight. The mid-bass driver is very robust with a fully cast magnetically shielded aluminium frame, the tweeter is very good but highly susceptible to finger prod damage and don't touch the connections on the back because on mine one terminal moved a fraction and severed the hair thin coil wire! Generally any tweeter dome dents can be pulled back out with adhesive tape but will probably leave a mark although I doubt it damages the sound. Unfortunately Kef uk no longer have spares. There is a 45 degree floor to the upper chamber which is also the roof of the lower chamber so it's not a square box, there is also a shaped reinforcing baffle half way up the lower bass section. In one side is a 6" woofer which is smaller than the 8" round side grill suggests, if only they had fitted a 8". On the other side is a matching grill that covers a bass reflex tube that travels halfway into the cabinet, turns through 90 degrees and goes up through the reinforcing divider and ends open in the upper part of the bass chamber. Overall a very solid construction. In both chambers there is plenty of wadding and I think in mine it was placed too tightly around the back of the woofers, I loosened it up and opened it out and there is more bass now. The crossover mounting screws needed a good tighten too. The crossovers look good with decently thick windings on the inductors. There are good quality HF and LF binding posts with metal jumpers and plastic inserts that need removing to use banana plugs.
Kef state in their literature that they :- 'found and solved an acoustic ‘shelving’ effect that causes an audible ‘lump’ somewhere around 600Hz in the midfrequency range. Most manufacturers accept this as a necessary limitation of budget speakers, but KEF engineers have succeeded in designing out this unevenness in the new Coda range by adding an extra filter section in the high order crossover circuit'. I'm prepared to believe them it does sound very natural.
There is only one professional review from tnt audio, perhaps Kef were promoting the Q series more.
In summary this is a very good speaker that was unbelievable value new, and even more so second hand. If you thought the coda 7 range was good this is even better.