The proverb may tell us that we can’t have our cake and eat it too, but it seems Krix has turned that proverb on its (proverbial) head with the Acoustix Mk2. Because with these speakers, you can have your cake and eat it too. And just in case you’re wondering what the hell that proverb means, we’d interpret as implying that you can’t have two things that are mutually exclusive.
How the proverb applies in this case is that when it comes to buying speakers, it’s a given that you have to make trade-offs. For example, you really can’t expect to have deep, solid bass if you are not prepared to put a pair of large floorstanding speakers in your room. Another example is that if you don’t want your speakers to be visible at all (by building them into a cabinet of some type), you can’t also expect them to deliver ‘hi-fi’ sound quality.
Krix’s Acoustix Mk2 speakers are proverb-beaters because despite their modest size, they will deliver bass that will have people looking around for the floorstanding speakers, and will also deliver true hi-fi sound even if you mount them inside a cabinet. And although they’re great stereo speakers, their driver layout means you could use one as a centre-channel speaker, guaranteeing truly seamless audio ‘pans’ from the left speaker across to the right when watching 5.1-channel movies. So it’s a great ‘home theatre’ speaker as well.
The Krix Acoustix Mk2 is essentially a perfectly symmetrical three-driver, two-way bass reflex design with twin front-firing ports. You don’t need us to tell you why it’s a ‘perfectly symmetrical’ design: one glance at the photograph accompanying this review should be all that’s required for that!
The two bass/midrange drivers use fibre reinforced moulded-polymer baskets to support doped paper cones, via a rubber suspension. Krix rates the ‘nominal’ diameter of the drivers as 130mm, and the overall diameter is 150mm, with a mounting hole diameter of 136mm, but the Thiele/Small diameter is 102mm, which gives aneffective cone area of 145cm² (Sd). Because there are two bass/midrange drivers, the area available for bass is double this, at 290cm², so if Krix had used a single bass driver, its overall diameter would have been around 243mm, which is one reason the bass is so solid. Each bass/midrange is equipped with a 25mm-diameter voice coil wound around an aluminium former that’s driven by a large, vented magnet assembly, with the whole being supported by an extremely solid cast-metal basket whose design incorporates under-spider venting.
These drivers are crossed (at 2.1kHz) to a 25mm dual-concentric diaphragm tweeter with wave-guide central plug and ring-formed absorption chamber. The particular design is often referred to as a ‘ring radiator’ design, for which Danish company Vifa has two patents, so it was hardly surprising that the tweeter Krix uses on the Acoustix Mk2 is, in fact, made by Vifa itself, the particular version being an XT25SC, which has a neodymium magnet.
The crossover (made in-house by Krix itself as, indeed, are the Acoustix Mk2’s cabinets) comprises two cross-mounted inductors (one air-cored, one ferrite-cored), three Krix-branded metalised polypropylene film capacitors and a single cermet resistor, all of which are mounted on a robust PCB. As with many designs, the crossover is easily accessible, being mounted to the rear of the speaker terminal plate.
Although theory has it that two small bass reflex ports will work as well as one larger bass reflex with twice the area, this doesn’t actually work out this way in practise when you’re using two bass drivers, so we were pleased that Krix uses two ports on its Acoustix Mk2. So, appearances to the contrary, the ports are not there just to make the speakers truly symmetrical… the speakers do really work better with this layout. That the ports are on the front baffle, rather than the rear, means that the speakers can be mounted inside furniture items (an AV cabinet, for example).
The Acoustix Mk2 cabinet is made from 17mm MDF, and is internally braced. It’s lined with soft white non-carcinogenic foam damping material. The cabinet is available in a variety of standard finishes. In a black vinyl finish, the speakers retail for $1195 per pair. In a veneered finish the RRP increases to $1395 per pair for your choice of Black Ash, American Cherry or Atlantic Jarrah, or two new “environmentallyfriendly” finishes called Cola and Ironwood, made using plantation-grown wood. (You canalso choose any finish you like, but this option will set you back $1745 per pair.) We thought the black vinyl finish was plain, but if you’re mounting them in a cabinet, this won’t matter. If the speakers are going to be visible, we’d pay for a veneer.
One of the several advantages of the way the three drivers are laid out in the Acoustix Mk2 is that because the tweeter is adjacent to both bass/midrange drivers, you find that even when the speakers are very close to the listening position, you still hear the acoustically ideal ‘point source’, so sounds do not appear to ‘move’ vertically depending on their frequency, as they do with larger, multi-driver systems. This makes the Acoustix Mk2s absolutely ideal for near-field listening and/or use in smaller rooms.
For our listening sessions, we used the speakers just as we would conventional two-way speakers, and tried various positioning options. Our favourite was to place the Acoustix Mk2s on stands, where they delivered, to our ears, their best performance, but they performed almost as well on shelves and against a wall. Bass was at its ‘biggest’ and best in the shelf and wall-mount positions, but even stand-mounted we were surprised at the depth and power afforded by the dual bass/mid drivers in the Acoustix Mk2: they really punched above their weight. We were hearing far better, far deeper bass than we’ve heard from any small two-driver two-way system, to the point where it actually rivalled some of the smaller floorstanding models we’ve auditioned.
When you’re listening for yourself, we’d recommend you play a track with big fat bass and prepare to be surprised!
Higher up in the audio band, the Acoustix Mk2s became even more impressive, as we learned when auditioning a new EP, Heartstrings, from The Phoncurves. Listen to the second track, ‘Lover’, and right from the a cappella intro through the sparse piano backing you’ll be spellbound by the clarity of the sound, the speakers’ ability to separate not just the live harmonies but also the multi-tracked vocals and the amazing detailing that lets you hear even the sound of Naomi Hodges’ lips parting before she starts to sing. Then, when she harmonises with Abbie Roberts, the resulting resonances are gloriously coloured. (Download the FLAC of the track and be enchanted!)
We loved the high-frequency sound too: the glockenspiel on Archer & Light’s ‘Our Love is Confetti’ was beautifully rendered with crisp strikes and smoothly decaying notes. Very clean, very pure and very nicely integrated with the top end of the response of the bass/mid drivers… which is a difficult trick to pull off. There was, perhaps, a tad less ‘shimmer’ than some of the finest tweeters around, but lots more than tweeters in many other speakers at this price-point.
Krix makes all its speakers individually, and by hand, and this personal attention to detail was revealed by the soundstaging, which was outstanding. You get not only an accurate picture of where all the performers are standing, but also of the stage depth, resulting in a totally immersive listening experience.
If you’re looking for big sound from a pair of bookshelf speakers, it doesn’t come any bigger than from the Krix Acoustix Mk2.
+ Great bass; Pin-point imaging; • Concealable and flexible
- Black vinyl finish is plain
Frequency response: 50Hz–40kHz
Efficiency: 89dBSPL (2.83v/1m)
Crossover frequency: 2.1kHz
8 ohms (minimum 4.3ohms)
Enclosure type: Bass reflex, front vented
Enclosure volume: 14 litres
Dimensions (whd): 450 × 180 × 300mm
Warranty: Five years
Contact: Krix Loudspeakers Pty Ltd
Telephone: 1300 005 749