User manual FOCAL UTOPIA BERYLLIUM LINE

[. . . ] We are pleased to share with you our philosophy : "the Spirit of Sound". These high-performance speakers feature the latest technical developments from Focal-JMlab in terms of speaker design, whether it is for high fidelity or home theater systems. In order to make the most of these speakers and enjoy the maximum of their performance, we advise you to read this user manual. However, due to its nature, certain special precautions should be observed to avoid exposure to unnecessary risk. [. . . ] But the utilisation of large pole parts generates a problem of flatness. The bonding beetween pole piece and magnet is not consistent and generate magnetic losses. â· Polypropylene/Plastics a material relatively heavy, but with good internal damping properties. Not especially stiff and the sound tends to lack detail and precision. â· 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. 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. 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 "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. Creating a special virtual source capable of delivering a coherent sound without any loss of audio quality over space. the scale of the audio spectrum to be reproduced imposes unavoidable physical constraints. To appreciate this, you only need to consider the wavelengths to be produced. V is the speed of sound in air (340m/s) f is the frequency of the signal to be reproduced Therefore at 100Hz the wavelength = 3. [. . . ] In addition to the constraints imposed on the tweeter at low frequencies, there is also another very critical aspect: the phase behavior of the loudspeaker and crossover combination in this critical region. The ear and the auditive system are extremely sensitive in the zone 2-2. The midrange drive unit and its crossover must display an amplitude response that is "the exact mirror image" of that of the tweeter and its crossover. For this criterion to be met, the phase between the midrange and tweeter must be perfectly matched for the two to overlap and sum perfectly and create a balanced tonality. [. . . ]