The Vortex is based on the highly successful Epicentrix and has been designed to deliver perfect timbral matching to the Harmonix main speakers. This same tweeter is also used in the Phoenix and Apex floorstanders meaning the Vortex can also be used with a wide range of Krix products. The dual 165mm bass drivers, single midrange and 28mm tweeter used in the Vortex are identical to those in the Harmonix ensuring the 'audio stage' is seamless in it's transition from left to right. Focus is on vocal clarity, midrange depth and a dynamic bass response. Experience the sonic strength the Vortex will bring to your home theatre system.
Most home theatre systems fail to realise their full potential because they are being handicapped by an underperforming centre channel speaker: one that is too small and too wimpy to do the job properly.
Many people are happy to have quite large front-left and front-right speakers flanking their screen, panel or TV, but then compromise when it comes to the centre-channel speaker, putting in one that is much, much physically smaller than the main front speakers and one that has a narrower frequency bandwidth. The problem with this is that when you’re watching movies, the centre channel is usually delivering more of the movie soundtrack than either of the front-left and front-right speakers, and often more than the two of them combined.
The result, of course, of using a small centre channel is that such centre channel speakers are always being outweighed and out powered by the rest of the system. South Australian loudspeaker maker Krix has changed all that with its Vortex centre channel loudspeaker.
The Vortex is large. Very large. It’s not too far short of a metre wide (OK…it’s actually 725mm wide) and is 230mm high and 383mm deep. This results in an internal volume of 42 litres, which is very nearly as capacious as Krix’s highly regarded Harmonix floorstanding stereo loudspeakers. This is not surprising, because the Vortex shares exactly the same set of drivers as the Harmonix. Yes, it’s a centre channel, but it’s a four-driver three-way centre channel!
But it’s not just size you need to take into account with the Vortex: there’s also the weight to consider. At 24 kilograms the Vortex may not weigh quite as much as the Harmonix, but it certainly weighs more than several other of the floorstanding speakers in Krix’s range and unlike those floorstanding loudspeakers, which by definition stand on the floor, the Vortex will need to be supported by your equipment rack or stand.
Treble above 2.1kHz is handled by a 28mm soft-dome tweeter that sports a ferro fluid cooled neodymium magnet. Immediately below this tweeter – and responsible for handling the frequencies between 340Hz and 2.1kHz – is a 130mm diameter paper cone driver. This driver has a 26mm voice coil, an aluminium coil former for improved power handling, and a copper shorting ring to limit excessive driver excursion.
Bass is handled by a pair of 165mm diameter polypropylene cone drivers. Each has a 33mm diameter voice coil wound around a heat-dissipating aluminium former, a ventilated spider and an aluminium flux stabilisation ring.
The speaker is biwirable, with proper gold-plated binding posts, and is bass reflex loaded. Instead of using just a single large port, Krix uses two smaller ports, located either end of the front baffle. This not only aids with symmetry of bass delivery, it also means that each or the ports is exactly equidistant from each of the bass drivers, so both will have a uniform output.
Krix rates the impedance of the Vortex at 4 ohms, its sensitivity at 91dBSPL and claims an ‘in room’ frequency range of 35Hz to 20kHz.
The price I have listed in the information panel accompanying this review ($1,095) applies only if you choose one of Krix’s three vinyl finishes: Black Vinyl, Atlantic Jarrah Vinyl or American Cherry Vinyl. If you’d prefer a real timber finish, you need to add another $100. The timber veneers available are Black Ash, Atlantic Jarrah and American Cherry. I should point out, however, that Krix does offer a ‘custom’ finishing service where you can place a special order to have almost any paint or veneer finish you want. For this, you’d first have to contact Krix to discuss your finish and request a quote.
Although the Vortex is large enough – and solid enough – to support even the largest CRT TV, I would not recommend you put one directly on top of it, because unlike some of Krix’s other centre-channel speakers, none of the drivers inside the Vortex are magnetically shielded. Those of you with plasma or LCD panels are free to place them on top of the Vortex.
You may be wondering why centre channel loudspeakers are normally placed sideways. It’s not for performance reasons, but for cosmetic reasons…all due to crowding at the front of the room.
Most horizontally-located centre speakers have a problem: they suffer from left-right dispersion problems in the upper midrange. The reason is that they have a tweeter in the middle, and then two bass/midrange drivers producing frequencies up to a couple of thousand Hertz on either side of it. But if you are offset to either the left or the right, then the path-length of the sound from the two drivers to your ears differs, so there’s uneven interference between the two drivers. (At 2kHz, the wavelength of the sound is about 17cm.)
However, if you use a single high-powered midrange driver to deliver frequencies down to 340Hz (where the sound wavelength is one metre) as Krix has done with the Vortex, there is no such problem. While auditioning the Vortex loudspeaker, I made a particular point of trying all the available positions first on the couch in front of the TV, and then sitting much further away in separate chairs to either side of the couch, and no matter how far off-axis I sat, the character of the voices produced by the Vortex remained perfectly steady.
It is impossible to overstate how essential it is that a centre channel deliver voice character accurately, because it’s about 90 percent of what it does in 5.1 channel mixes. So it needs natural reproduction, which means a flat frequency response and uncompressed dynamics. Just as importantly, the sound was very precise and tonally neutral.
As to robustness, we have one DVD-Audio disc that always causes trouble for centre-channel speakers. The reason it causes such grief is that mastering engineers, perhaps in the pay of some loudspeaker repair company, mixed the centre channel with prodigious levels of deep bass rather than hiving it off to the LFE channel, as is usual. The result is that even some otherwise quite competent centre-channel speakers have problems with this track, because even with an 80Hz crossover, enough of this deep bass can make it through to bottom their cones!
So I set the Vortex to ‘Large’ with my home theatre receiver to ensure it received all the bass, spun up the disc, advanced the volume control to a ridiculous level, and waited to see what would happen… and what happened was that the Vortex delivered a musical performance with tightly controlled and remarkably deep bass. Not as deep as if I’d set it up properly (I would suggest setting a crossover of 50Hz for the truly deep bass to go to a subwoofer that can reproduce it with greater impact), but it coped wonderfully. That is indeed impressive. (And for those who want to try this torture test for themselves, the disc is ‘Brain Salad Surgery’, by Emerson, Lake and Palmer.)
While, clearly, this speaker would be best-suited for use with other Krix speakers, particularly for the front left and right channels, my opinion is that if you already have a pair of high quality front speakers – especially if they have a flat frequency response – and need a high-quality centre channel to go with them, the Vortex would be an ideal choice
If you already own Krix speakers, then this is definitely the centre channel for you. But even if you have another brand of speakers and want to upgrade your centre channel, the Krix Vortex is worth an audition. The question is likely not to be whether it is good enough for your system, but whether your other speakers are good enough for it!
- Australian HiFi - Australia , Stephen Dawson