Loudspeakers, Art or Function ?
"A loudspeaker is to the ear what a pane of glass is to the eye. Like glass, which sometimes distorts what one sees through it, loudspeakers don't always reflect the integrity and detail of the original."
After Laurence Dickie (known as 'Dic') completed his electronics degree at Southampton University, England he worked at B&W Loudspeaker's Steyning research & development labs. Although he started with electronics, his real passion was loudspeakers, and B&W recognised his creative talents when he came up with the multi-panel Matrix enclosure stiffening technique that has been used in all of B&W's top-of-the-line ranges since 1987.
The success of Matrix gave Dic the license to pursue his ultimate loudspeaker, and this turned out to be the original cochlea-shaped Nautilus in 1994. Sales of this extraordinary speaker might have been modest, but as a hi-fi icon, and from a marketing perspective, its value has been incalculable. Not to mention all of the trickle-down technology that was subsequently used in B&W's Nautilus range of speakers to great effect.
Post Nautilus, after spending fourteen years at B&W, he left and started up his own operation called Blast Loudspeakers, working on designing his own ideal drive units, and doing consultancy for other companies, such as Blue Room and Turbosound.
When B&W's part-owner Robert Trunz left B&W in 1996, he took with him the Blue Room sub-brand and re-established his association with now freelance Dic. When Robert then subsequently emigrated to South Africa, he happened to meet up with a couple of guys, he knew in the hi-fi business; he discovered they had ambitions to start up their own loudspeaker manufacturing operation, and were looking for engineering assistance, so he introduced them to Dic.
Dic picks up the story: "In 2001 Robert suggested I should fly down and meet Philip (Guttentag) and Bruce and Dee (Gessner), who were based in Kloof, just outside Durban in KwaZulu-Natal. Both had worked previously in the hi-fi business but were now running a successful professional acoustic consultancy business so in a way our careers had followed similar paths. We got on well together and developed an immediate rapport. I was very impressed by the passion and enthusiasm they were bringing to the project."
"Philip and Bruce told me about their intention to build a genuine hi-fi loudspeaker in South Africa. They showed me the attractive shield-shaped enclosures they had designed - a nice touch of Zulu influence here - and said that they planned to use OEM drive units. I pointed out the drive unit designs I had been working on could well provide a basis for what was needed, and we then started looking in more detail at the engineering involved."
When Dic joined Vivid, they used a Nautilus to voice the original active B 1 so that could compare & contrast against the Nautilus. What was immediately apparent was that the new Vivid drivers that he had recently designed were substantially less coloured than those he had used in the Nautilus.
Dic set out much of his agenda as when he did that original Nautilus, and a number of the basic principles used then may be seen again here in the B1. For example, he believes in creating pistonic drive units -i.e. drive units that are able to operate in a substantially linear manner throughout their intended operational bandwidth, with mechanical breakup modes kept more than two octaves beyond the cross-over roll off frequency.
To this end the B1 uses anodised aluminium alloy diaphragm drivers throughout, in a ‘three-and-a-half-way’ configuration, with tightly defined, fourth-order crossover filtering, so that each driver is restricted to its appropriate operating band. Dic continues: "The two identical 7" bass/mid drivers with 5" alloy cones are mounted back-to-back here. They're mechanically coupled so that reaction forces cancel out, and the one facing backwards just provides additional bass - it's fed via a first-order roll-off operating above 100Hz. These drive units have a very open and unobstructive frame, so there are no cavity resonances. The short-coil/long-gap motor section has some unusual features too, building on the work I've done to improve cooling and reliability and avoid power compression with Pro Audio drivers.
We also use special radial magnets, with the field running from inside-to-outside rather than between the flat surfaces of the ring. This helps focus the magnetic field and reduces stray flux, so that additional shielding isn't needed. The air beneath the central dome (within the voice coil) is ventilated through the motor, and the tendency for this to create a Helmholtz resonator is avoided by using a heavily perforated former for the 2" voice coil."
"Besides mechanically coupling the two cone drivers to cancel out reaction forces, we also us O-rings to decouple them from the enclosure above 50KHz, to avoid exciting any panel modes. The enclosure itself is moulded from a polyester resin loaded with carbon fibres, and its curved shape has acoustic benefits inside and out.
The 7" bass drivers are loaded by twin reflex points, situated on the front and the rear (so you can look right through), again to balance out reaction forces."
"The front-facing bass/mid driver hands over to a 2" dome midrange driver at 900Hz, primary in order to ensure that even and wide dispersion is achieved throughout the critical presence band.
We actually use the same cylindrical magnet elements for this driver as we use in the bass/mid drivers, which makes life a little simpler. Inside the enclosure, a tapering tube transmission line is fitted behind this mid dome to absorb rearward radiation without creating reflections. An internal tapering tube is also used behind the 1" alloy dome tweeter, and here we've used finite element analysis to the magnetic flux. With careful magnet shaping we've managed to achieve an extremely high flux of 2.4 Tesla."
UK HiFi writer Paul Messenger queried the need for such high magnetic power (most hi-fi tweeters settling for around 1.6 Tesla), and Dic pointed to two advantages:
"The poles will always stay saturated, which reduces the effect of the steel while the high efficiency also improves headroom and hence reduces power compression. And the use of a large padding resistor also improves the stability and consistency of the effective driver load on the crossover network with different power levels", he explained.
Vivid's Aluminium Tweeter versus Diamond Tweeter
While the Vivid D26 tweeter (42 kHz break-up) is outperformed in the extreme high frequency response compared to other manufacture's Diamond tweeter (typically 60 kHz break-up); incidentally both tweeters perform well beyond human hearing. The Diamond tweeter is physically, considerably heavier than the aluminum D26, due to the thicker layers of diamond deposits that need to be laid down to achieve structural rigidity than the aluminum D26 The Vivid D26 is 9 dB more efficient than the diamond tweeter; that's eight times more efficient ! Please review Vivid's Super Flux Magnet Technology employed in the D26 tweeters.
In real life, the D26 is padded down to 89 dB in the B-1, K-1 and 91 dB in the Giya, so the tweeter's 9dB of extra headroom gives us far less power compression for the same SPL and as a result of the higher efficiency, the Vivid D26 is just ticking over compared to the others. Meanwhile the Diamond tweeter is run at or near its maximum output, so at high SPL or high transients, the diamond tweeter will perform in a non-linear fashion and sound harsh & fatiguing.
Vivid in California
Back in 2005, Philip Guttentag come to visit us here in Capistrano and played a pair of K-1 in our office. He simply plonked them down in front of our custom QUAD ESL57 electrostatic speakers (non-magnetic stainless steel frames) and they immediately threw a wide soundstage, well defined bass and the clarity that we were already so accustomed to.. Pandora was so impressed that she told me that these were the first speakers that she could live with in our office. The Quads had ruled the roost there for over a decade.
Fast forward to 2008, we have the Giyas in our living room and quite simply these are world-class speakers. In the same room over the past decade we have the good fortune to listen to:
Avalon - Edilon
B&W - Nautilus 801
Classic Audio Reproductions - T-3.1
Dunlavy - 4
Eggleston Works - Andra II
Eggleston Works - Savoy
JM Lab - Utopia Be
Lumenwhite - Silver Flame
Wilson Audio - MAXX 2
The Giyas have an accuracy in the bass unrivalled by any other speaker. They are capable of reproducing texture & subtleties, hitherto unreproduced. We use analogue 2 track, 15 ips Master Tape as our Reference and the Giyas bass definition is unparalleled.
Besides the remarkable sonics, the speakers are drop dead gorgeous - truly functional art. The fit & finish is superb; we live with what we represent and are delighted that the Giyas look so beautiful from all angles.
Below, you will find that Vivid Audio have a wide range of speakers to suit all sizes of rooms and while perfection is not inexpensive, the smaller speakers are quite affordable.
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