THE CHOICE
Designing a loudspeaker is the occasion to keep thinking and tracing back several aspects of the recent history of high-fidelity. The design approach of Albedo springs up from a deep analysis of two basic questions in the field of sonic reproduction: the first concerns technological development, the second refers to the actual demands of users in terms not only of pure performance but also of reliability and easiness.
Three are the main aspects of the Albedo project: acoustic phase control, equalized transmission line loading and ultra stiff mechanical coupling.
Since the beginning, these elements have been considered fundamental to accomplish specifics of any project. The phase response is necessary for an accurate transient reproduction and, as a consequence, for a correct focusing of the acoustic sources and rendering of the sound perspective. To achieve these objectives, the correct geometrical setting of the transducers must be combined with the crossover network design. It is to be remarked that, in view of recently discovered psycho-acoustic aspects of sound perception, the coherence of reproduction in the time domain plays a major role also for tonal balance, role at least as important as the linearity in the frequency response.
The choice of the transmission line system is imposed by our firm belief that it provides the best combination of a relevant bass lift together with an uncompromised quality in tonal balance and time response. Therefore, to reach this optimal behavior, a totally innovative system has been worked out, making a substantial step forward in the transmission line technology.
Concerning the pure mechanical point of view, the target of a perfect working of the drivers is achieved by means of an ideal driver-cabinet coupling and cabinet-support-environment chain and by suppressing the negative 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. Accuton loudspeakers have ceramic, ultra stiff diaphragms able to produce excellent transient response and very low distortion.
History
In the early 90s, Massimo Costa (editor in chief of DIY Italian audio magazine Costruire Hi-Fi) and Giuseppe Pucacco (PhD from Department of Physics from University of Rome) faced the general issues of transmission line loudspeaker systems, formulating for the first time a rigorous mathematical model to describe this specific acoustic configuration. The first outcome of this research was the development of proprietary software to model with great accuracy the behavior of any classical transmission line system. This work was very important as it allowed to highlight the limitations in other projects developed until then, and the inconsistency of several myths existing in the industry with respect to the very concept of transmission lines. In the end, they concluded that although the transmission line system has been the subject of studies for more than half a century, it still deserved further effort in research and understanding. Therefore, they worked at identifying the most suitable absorbing acoustic stuffing and its best disposition inside the duct, with the objective of not penalizing irrevocably the system efficiency. A long and thorough investigation on the fibrous material made available in today’s industry, enabled to eventually identify the answers they were looking for. Obviously, these basic principles were complemented with other completely original acoustic solutions like Helmholtz resonators used to equalize the duct emission. The outcome of this volume of studies gave birth in 1995 to the first Albedo project, a two-way loudspeaker system equipped with a small 4” driver, which was introduced by another company onto the Italian market. It had a good commercial success with excellent reviews on specialized hi-fi magazines. But this is just the past.
