The Twin6 Be is an active, 3 way, professional nearfield/midfield speaker (3 built-in amplifiers – 2×150 +100W rms), comprised of two 6.5 inch (16.5cm) “W” cone sandwich composite drivers, loaded by two large section laminar bass ports and a Focal inverted dome pure Beryllium tweeter. Both 6.5” drivers handle low frequencies but only one of the two (selectable) is passing lo-mid frequencies.
The reversed dome tweeter is a hallmak of Focal. As a result of more than twenty years of development into a tweeter that could produce a high output, but without requiring high energy input and without increasing directivity. And now the company is ready to make a major leap forward with the introduction of the pure Beryllium version.
SM6 line tweeter
The main advantage of the inverted dome tweeter or the full range tweeter…
The experience acquired over the last twenty years has allowed Focal-JMlab to push back the limits of reversed dome technology and the work on the suspension, driver shape, adhesives and materials have at each stage produced an improvement in linearity and bandwidth.
The research began by testing fibre domes, as a simple and less sensitive way to validate the advantages of the reversed dome with regards to energy response. Then the company introduced more rigid metal domes to extend the response in high frequencies, and with Titanium producing the most impressive results it has proved to be the most relevant choice. Today to exceed these limits and particularly to extend the response to nearly 40kHz, we need to move towards a material even lighter and more rigid. Already competitors have moved to introduce super tweeters to satisfy the extreme requirements of the new high-bandwidth sources. However, Focal-JMlab does not believe the adoption of the super tweeter is to be a satisfactory solution.
First of all, the distance between the tweeters, for frequencies where the wavelength is of the order of cm, poses serious problems of coherence. A filtering is imposed which destroys, by the losses and distortion of phase, the benefits introduced by extending the frequency response. So it is advisable to point out that simply extending the high frequency response is not an end in itself, as the ear is most sensitive to transients. The improvement with regards to the impulse response is only perceptible at a tweeter output far beyond the 20Khz, limit and to far beyond the perception of human hearing. We should not forget that Focal-JMlabÕs first objective was to design tweeters offering an optimum coupling, being able to integrate with the mid-range at sufficiently low frequencies and before the output of the mid- range begins to tighten or beam. Thus the only successful solution is, therefore, to produce a tweeter with an extended response that covers more than five octaves from 1 000Hz to 40 000Hz.
Beryllium – The ideal material for a dome. An ideal dome must combine lightness, rigidity and damping. Currently, only one material offers the possibility of a significant improvement. Beryllium. BerylliumÕs density is 2.5 times lower than Titanium and 1.5 times lower than Aluminium while its rigidity is 3 times higher than Titanium and 5 times superior to Aluminium. Which means that for a dome of identical mass, a Beryllium version is 7 times more rigid than one made of Titanium or Aluminium – which have similar rigidity for a given mass. Moreover, the velocity of sound in a Beryllium dome is 3 times faster than a Titanium version and 2.5 times faster than Aluminium. However, the manufacturing of Beryllium remains very difficult and its production has been limited to just three countries: the United States, France and Russia. To date, Great Britain, Germany and Japan do not manufacture pure Beryllium, rather using it in the form of an alloy. Beryllium is an excellent high-tech metal – the only metal able to scratch glass – it is only used in strategic applications in the aeronautical and military industries and consequently, its unique characteristics make it extraordinarily expensive, much more than gold and nearly 100 times that of Titanium.
The only solution for Focal-JMlab – Control the manufactruing process. The analysis of the mechanical characteristics inevitably leads to BerylliumÕs choice as the ideal material for a tweeter dome. However, a major problem exists because no company has been able to manufacture such a dome. To arrive at a solution, required Focal-JMlab to conceive a process for forming a pure Beryllium dome*. And after two years research and investment, the company now posses a machine to carry out what was considered as utopia. Technological it is a world’s first and certainly exceeds anything currently found in the audio field.
And the result is in line with the company’s hopes and expectations of an outstandingly detailed loudspeaker which extends to nearly 40 Khz while maintaining a perfect impulse response. Beryllium tweeter The reversed dome tweeter is a hallmak of Focal-JMlab. As a result of more than twenty years of development into a tweeter that could produce a high output, but without requiring high energy input and without increasing directivity. And now the company is ready to make a major leap forward with the introduction of the pure Beryllium version.
* In the past certain manufacturers have attempted to use Beryllium for the construction of a direct radiating tweeter dome. However, they have actually only used Beryllium as a surface coating on a dome structure leading to different characteristics to anything achieved with pure Beryllium.
New audio formats have considerably risen expectations as far as amplification is concerned, in terms of frequency response and energy supply in the bass end. BASH® technology is a unique class of amplification capable of meeting these requirements simultaneously thanks to a wide frequency range and an efficiency reaching 85%.
Keeping the best of class AB, while allowing the efficiency of class D; BASH® technology makes the most of both worlds to achieve an amplification with no qualitative compromise.
The audio performance of class AB.
BASH® technology contains a class AB amplification stage combining very wide frequency extension and remarkable sonic quality (after class A, class AB is known to give the highest level of quality in audio amplification). The obtained performance greatly helps precision in the adjustement process during the mixing stage, as well as easy and predictable transfer outside the studio thanks to even spectral balance. BASH® was chosen to power the SM6 line as a perfect match with Focal Profressional philosophy : develop working tools offering outstanding sonic neutrality.
With a three times higher efficiency
The poor efficiency of class AB (10 to 30% in musical programs) makes it far from ideal to drive low frequency transducers demanding a high level of energy, in a compact format and limited space. To overcome this, BASH® technology includes a switching section, similar to class D, which is used to modulate the supply voltage depending on the amplitude of the audio signal. Thus the class AB output stage has its supply rails continuously kept to a minimum voltage, and minimal energy is wasted inside the output transistors.
While the benefits of class AB are preserved, this process brings efficiency up to 85%, in the same order as class D (90%). As a result of losses reduction, the dissipated heat is significantly lowered.
This translates into a minimal space required by the amplifier for an impressive output power, making it possible to keep the sizes of the cabinets compatible with dimensions of small or mid size control rooms.
The AB class amplification technology uses a stable supply voltage. Losses are directly proportional to this high supply voltage. The BASH® technology uses a “by request” fluctuating supply voltage. As the power input of the amplifier is seldom implicated, this voltage remains quite low on average or even very low at low level. The AB class amplification technology uses a stable supply voltage. Losses are directly proportional to this high supply voltage. The BASH® technology uses a “by request” fluctuating supply voltage. As the power input of the amplifier is seldom implicated, this voltage remains quite low on average or even very low at low level.
Bash® Technology Amplifier have sound quality of AB class and efficiency of D class.
Composite Membrane Technology
For more than 15 years the composite cone sandwich technology is a Focal-JMlab exclusivity. The “W” process, first initiated in 1995 with the Grande Utopia, provides now a true optimisation of the frequency response.
Properties of a drive unit membrane
Three parameters are of prime importance: mass, internal damping and stiffness.
• Stiffness allows the cone to behave as a piston over a wide range of frequencies, especially important at bass frequencies for low distortion.
• Low mass delivers maximum acceleration on transients for the best reproduction of fine detail.
• Internal Damping damps out any ringing or vibrations in the cone structure that would otherwise color the sound.
• Paper a light material, though not very rigid, but with reasonable internal damping. Sound often suffers from a “cardboard” coloration.
• Polypropylene/Plastics a material relatively heavy, but with good internal damping properties. Not especially stiff and the sound tends to lack detail and precision.
• A simple woven aramid fibres cone (not a sandwich type construction) uses a resin to seal the cone and bring about the rigidity required, but this tends to lead to a dull plastiky coloration.
The sandwich structure Focal-JMlab
During the mid 1980s, a new type of cone was developed and patented by Focal JMlab which combined low mass, stiffness and high internal damping; the “Poly-K sandwich”.
Using woven aramid fibres tissue skins and a core of hollow microspheres of glass mixed with a resin, this structure exhibited extremely high rigidity and low mass. The damping could be controlled by the properties of the core.
Since this original construction, the process has been refined and developed to produce a new generation of aramid fibres sandwich. The major advance in the construction of this cone is the use of a special structural foam in place of the resin + microballs. This foam is used primarily in the Aerospace industry; no other foam offers the same high ratio of stiffness/mass.
The name “W” is derived from Verre-Verre (Verre = Glass). The “W” cone uses two very fine tissues of woven glass that are lighter and thinner than aramid fibres. In addition, the molecular bond between the foam and the glass tissue is far superior to that of the aramid fibres. This results in a cone structure which is mechanically more stable and with superior stiffness. This construction allows us to further optimize the transmission speed of the sound wave in the cone. This new construction process allows the amount of internal damping in the structure to be very accurately controlled by varying the thickness of the foam: the thicker the foam, the higher the damping factor.
The relationship between the thickness of the glass tissues and the foam core allows us to finely optimize the cone structure depending on the particular application and the frequency area to reproduce.
The “W” cone produces an extremely transparent and neutral sound free from coloration and distortions normally associated with loudspeakers. Its only limitation, the price; more than ten times the price of a quality paper cone. System
Frequency response 40Hz-40kHz
Maximum SPL 115dB SPL (peak@1m)
Type/impedance Electronically balanced / 10kOhms
Sensitivity Adjustable, +4dBu ou -10dBV
LF/MF amplifier stage
LF amplifier stage 150W rms, BASH® technology
LF/MF amplifier stage 150W rms, BASH® technology
HF amplifier stage 100W rms, class AB
Mains voltage 230V (1.6A fuse rating), 115V (3.15A fuse rating)
Connection IEC inlet and detachable power cord
Input level switch
Speaker (left/right) switch
LF and HF contours (potentiometers)
Power ON/OFF switch, mains voltage selector
Indicator Power on LED
Woofer 2x”W” composite sandwich cone, Focal 6W4370B 6.5″ drive unit
High frequency Focal TB871 Beryllium inverted dome tweeter
Shielding Integral through cancellation magnets or by magnet design
Construction 19mm MDF panels with internal braces
Finish Real red veneer sides – Black on body
Dimensions (HxWxD) 250mmx500mmx340mm (9.8″x19.7″x13.4″)
All specifications are subject to change