THE TECH INSIDE
The transmission line systems based on the classic theory are quite simple to imagine: the low-end driver produces a front emission in the environment and a back emission in a duct uniformy stuffed with a fibrous material. The emission of the line port should combine with front one in such a way to extend and regularize bass range.
Starting to compare the theoretical predictions with the laboratory measurements, the result is that between theory and measurements there are substantial differences. For this reason, we use an our own simulation program, able to compute the response of real TL system.
In some models, a preliminary damping of unwanted resonances is obtained by covering the walls of the duct. using a suitable porous material. In this way it is possible to minimize acoustic losses reducing at the same time the counter-phase interference. When needed we use a special open cell polyurethane that well matches simulations, laboratory measurements and acoustic needs.
However this is still not enough, because dips in response curve due to main interference and its higher-order harmonics, would be still quite deep. The Helmholine System is one of the most original peculiarities of the Albedo projects, removing unwanted frequencies by means of a selective acoustic filtering provided by tuned Helmholtz resonators.The most attractive aspect of using these resonators is that, in addition to substantially reducing non-linearities, it contributes to regolarize acoustic load on the driver.
Even assuming to have the best available speaker, linear and extended in frequency and optimally matched to crossover filter, we will still have alterations in the frequency response (and time) due to a phenomenon always present: diffraction. The problem lies in the fact that our sound sources (speakers), have to be placed on cabinet baffle. The sound reaches the edges of this structure and, because of solid angle change, is diffracted, that is reradiated with a certain angle and changed in the phase. The edges of the cabinet thus become new virtual sources of sound with different phases with respect to the direct main emission. The sum of the refracted components with the direct emission, produces a number of modifications of the global emission given by the cancellations and reinforcements which gradually occur in frequency.
This behavior is more obvious with tweeters because of dimensions of panel. Generally, front panel of the speaker has a high aesthetic role and its shape must meet other needs than those strictly dictated by the acoustics.
The idea behind the DSD (Diffraction Shaping Device) is to weaken the wave energy in the pathway between the source and the edge of the panel and have a diffraction the most modest possible. It is a kind of micro perforated panel, back filled with absorbing material. At the resonance frequency, the system captures the sound wave and disperses into heat, reducing diffraction and improve tweeter response.
Concerning the pure mechanical point of view, the target of a perfect working of drivers is achieved by means of an ideal driver-cabinet coupling and cabinet-support-environment chain and by suppressing the bad effects due to the modes of resonance of the whole mechanical system. In addition to these design criteria, we adopted the transducers that better enjoy these features.
In 1984 the Backes & Müller production engineer Bernhard Thiel invented an electrochemical process to produce very thin sheets of extremely hard corundum (Al2O3) out of shaped aluminum foil. This patented procedure allowed the manufacturing of very stiff, light weighted and highly damped loudspeaker membranes, features impossible to find at the same time in traditional materials used for this purpose.
Accuton loudspeakers have ceramic, ultra stiff diaphragms able to produce excellent transient response and very low distortion. They are in matched pairs to warrant the smallest deviation from nominal specifics contributing to a firm soundstage.
A thin dome of diamond is ideal for a tweeter because the stiffness to weight ratio of this material is really unsurpassed. A concave dome is used because the moving assembly is more rigid and better damped than convex domes, and it also shows a better dispersion.
For this reason, the sonic character of diamond tweeters is not what you could expect, an overly “brilliant” sound, but it is just the opposite. The diamonds simply disappear, only music remains.
To reach best performance ever, we use advanced technologies available. Last updated digital measurement devices, precision microphones, displacement lasers, computer aided design and simulation software packages. Each component is carefully examined, tuned and controlled before shipping. Our quality control is derived from a total control for every step of manufacturing.
A lot of CAD
Any speaker is an original synthesis between design and tradition, where details match perfectly the unique Albedo view with the old tradition of the Marche region woodworking. What defines and makes us who we are is our passion, creativity, ingenuity and a sense of belonging to our country, Italy. A little piece of art in so much technology.