It’s no secret that Tannoy is one of the oldest and most prestigious audio brands in the world. Having been in the spotlight for decades, Tannoy has become synonymous with “speakers” in the UK, with the phrase “will be heard through the Tannoys” being used in reference to an announcement over the loudspeakers. The company’s Scottish factory is located near Glasgow, where it has been based for the last 35 years. Tannoy is also a major player in the United States, primarily for its beam-steering loudspeakers for concerts and stadiums. Its impact on the high-end scene is basically due to its Dual Concentric speaker, similar to a radiator of direct origin. The majority of Tannoy speakers, including high-end residential, traditional Prestige and professional audio models are made in Scotland. However, in order to maintain reasonable prices, entry-level residential speakers (the Mercury, Revolution and Precision lines) are manufactured in China. These days, the “designed in the West, made in the East” paradigm can be applied to any product with mass-market aspirations, including the HP laptop I’m writing this on.
The Revolution XT line represents a significant upgrade from the Revolution series. The trapezoidal chassis has been maintained, but the internal changes are far-reaching. The top-of-the-range model 8F, as well as the smaller 6F, are floorstanding speakers with bases with integrated decoupling spikes. The numerical designation refers to the diameter of the cone, and in both cases the design can be characterized as two and a half way. In the 8F, the coaxial woofer can work on the bass while being supported below 250Hz by an 8-inch woofer, with the filter being low-pass and second order. The coaxial tweeter and woofer are cut at 1.8 kHz using asymmetric filters: first-order high-pass for the tweeter and second-order low-pass for the woofer.
The woofers are powered by two chambers connected by an internal port. The lower chamber is smaller in volume and has air outlet to the outside through a channel facing downwards in the lower part of the chassis. This type of dual-chamber bass reflex alignment was already described in 1961 by George Augspurger in an article in Electronics World, but it has not had much commercial application since then. Compared to a conventional bass reflex, the dual-chamber design is tuned to two frequencies, usually an octave apart. As a consequence, compared to a conventional bass reflex, the double bass reflex is capable of controlling the excursion of the woofer over a greater range, up to a very deep bass. This was evident in the impedance graph which showed resonance peaks of a well-damped woofer. The minimum upper bass impedance kicks in at about 3 ohms while the maximum is about 40 ohms in the upper midrange.
The star feature is, of course, the new coaxial cone, said to be Tannoy’s new interpretation of its localized cone philosophy – and a huge milestone in the company’s more than 65 years of research and development. If you think you find some arrogance in that statement, think again. My own listening and measurements have convinced me that it really is a great success. There was a time when designers cluttered the front baffle with many cones, without regard for the potential resulting acoustic interference effects. And before Siegfried Linkwitz in the mid-1970s, filter design was merely an exercise in electrical engineering, without taking into account path length differences between individual acoustic centers. The published frequency response specifications for these multi-way loudspeakers appeared to be based on a single microphone position in which the cones integrated reasonably well. If the microphone was moved a few centimeters, the integration collapsed and there were serious response drops.
I have long been a fan of coax; They act as wide-range cones and can be considered improved versions of the 1930s dual-cone, full-range transducers such as the Lowther range. The first coaxial design, the Duplex 601, was unveiled in the 1940s by Altec Lansing. An improved version, the Altec 604, was introduced around 1945 and quickly became the standard studio monitor in the United States. A few years later Tannoy’s Dual Concentric design arrived and became the leading studio monitor in the UK and throughout Europe. Both designs used high-frequency waveguides, but the unique aspect of the Tannoy was that the woofer provided the final driver for the tweeter.
The ideal model of a focused coaxial cone, in which the acoustic centers of the tweeter and woofer are almost spatially coincident, has been difficult to implement in practice without having serious side effects. The tweeter usually sits on the magnet pole of the woofer. Cavity resonances and horn loading caused by the waveguide and woofer cone can color the response in the transition region between the two cones – a “cupped hands” coloration could be a common denominator for Tannoy coaxials. previous. In the new cone, a single magnet, dubbed the “Omnimagnet” by marketing folks, powers the tweeter and woofer, improving timing alignment and phase coherence. The tweeter diaphragm has a 1-inch diameter and is formed from polyetherimide, also known as PEI, a high-performance thermoplastic whose characteristics include great strength and rigidity at elevated temperatures. This is no ordinary dome; it is actually shaped like a donut or, if you insist on a precise geometric description, a torus, associated with an ogival phase connector. The phase connector is wrapped by a waveguide that goes further into the woofer cone. The waveguide is designed with an aggressive propagation rate that results in a shallower profile to improve high frequency dispersion through the mouth of the bass cone.
The end result of these innovations is a superb mid-range. I have not been able to detect any obvious coloration in the media. In fact, the vocal range is reproduced with exceptional timbral fidelity. My own personal experience, David Manley’s Lesley album, has never sounded so close to the original recording master. This is high praise, as very few speakers achieve this, regardless of their price. The voice is, harmonically, too fine or too coarse. Compared to its competitors, the Tannoy 8F hits the harmonic zone of the blonde and sounds good. The range from 300 Hz to 10 kHz left little to be desired when it came to textural purity, microdynamic integrity, and tonal accuracy.
The main reason for choosing a matching cone is coherence – the fundamentals of the music and its harmony originate from the same spatial location. So it shouldn’t surprise you when I tell you that the 8F generates a colossal soundstage, populated by a focused and well-defined image. The “sweet spot” was huge, much wider than that produced by a typical two-way design, extending it at least 15 degrees off-axis. The tonal balance and focus of the image remain stable even when you move your head considerably in the listening position; With the Tannoy you won’t need to bolt your head to the back of the seat. In particular, image stability was a real joy. This is not something that is often mentioned, but it reduces the mental energy required to accept the illusion of a believable soundstage. The 8F manages to effortlessly introduce you virtually into the acoustic space of the recording.
The most surprising thing was the transient speed, at the level of Formula 1. I did not expect it in a speaker of this price and the same goes for the transparency of its sound scene. For example, powered by the Perla Audio Signature 50 integrated amplifier, the combination achieved a very clean soundstage, eliminating what could have obscured the contours of the image. Associated with the unbalanced First Watt SIT-1 monophonic, the mids sounded sweet, with all the purity of expression that these reference stages are capable of. The musical lines soared effortlessly with dynamic conviction and minimal electronic intrusion. Again, the 8F is capable of decisively revealing differences between amplifiers, a testament to its resolving power. For the record, it offers a better image associated with valves, with which it also managed to embody a very convincing spatial impression.
At this price level you shouldn’t expect perfection. The fault is its performance at the extremes of the frequencies. I don’t mind the slight emphasis on the lower treble, but the real problem is in the mid-bass. At least in my living room, there was too much. In-room measurements showed a peak of about 7dB relative to the upper bass and lower mids about the octave from 50 to 100 Hz. Of course, the resonances were more noticeable below 300 Hz, so I was careful to average the bass response in different positions. It seemed logical that although the dual cavity and bass reflex alignment exerted firm control over the woofers, the port output was excessive. To test this theory, I placed a one-inch-thick wedge of acoustic foam in the space between the base and the bottom opening. The result was a 4dB attenuation of the peak and a much more satisfactory overall bass balance. When I reported my findings to Tannoy, they told me that they had concluded that for some stays, a foam plug should be placed in the port, and this would be included with future shipments. It is really a welcome evolution, as the user will be able to adjust the output according to his own room.
The Tannoy Revolution The price of the Revolution XT turned out to be $2,600.” Having lived happily with the Tannoy for several months, he was prepared to declare it a sensational entry-level speaker. But now I see that I need to correct that statement slightly – the only entry-level thing about it is its price. The wood veneer and level of finish does not speak of an entry-level product and, sonically, it works at a much higher level. I totally agree with Robert: The Tannoy achieves a virtuoso midrange that can compete with speakers priced around $10,000. I’m in no rush to get the Tannoy XT 8F out of my living room. And that’s a real compliment coming from someone who owns much more expensive speakers. Do yourself a favor and listen to the Tannoy – you’ll be glad you did.
