Music Through Technology - Deep Bass from small Enclosures
Bass performance is determined by the parameters of the driver, the crossover, the volume of the cabinet, and, if it is not a closed cabinet, the system of cabinet support for the woofer (for example, bass reflex, horn-loading, transmission line, and so on). Throughout our years of experience, we've noted the superiority of the Helmholtz resonator (known as bass reflex) compared to the other systems, if all influences are exerted according to an exact methodology. A perfectly tuned bass-reflex system with complementary designed drivers not only enables fast, solid bass foundation and slam; interestingly, it also affects the midrange, allowing the driver to breathe and sounding more natural and more free, compared to a closed cabinet.
Also, it was the best system for our quest to create relatively compact speakers that fit nicely – like furniture – into your living room, rather than dominating it. The bass performance we've developed exhibits such true deep bass that most listeners wonder how it's possible. One answer, besides the exact tuning of all parameters, lies in the choice of drivers and their cones; their quality and development really make the difference. To cope with the demands of handling high power and achieving fast and deep bass response, we have chosen long throw units: the wire on the voice coil layer is wound higher over a long distance, so that even at long strokes the voice coil is always totally within the magnetic gap. This enables very deep, undistorted bass. We compensate for the subsequent loss in efficiency with bigger magnets, an easy solution well worth its expense.
Our innovative technology for creating deep bass out of compact enclosures is the result of extensive research undertaken in the development of small-volume, flat cabinets dedicated to near-wall application. The task was to create new drivers with bass-function components that are externalised to the crossover and capable of creating a perfect bass response. Please read about this sound technology in our crossover technology page and in the description of the individual models of the WALTZ and SCHÖNBERG series.
The pressure within the speaker cabinet is extremely high. It´s indispensable for the Helmholtz resonator to work effectively that the cabinet be massive and absolutely airtight, with the obvious exception of the tuned port. Not only the cabinet needs to be built accordingly, but also, the reflex ports need two reinforcements. (1) We developed port tubes with a wall thickness so massive that it is not possible to twist or otherwise distort them with bare hands alone. (2) We screw the port tubes to the cabinet, absolutely the only way to ensure the solidity required. You'll find both methods of reinforcement on Vienna Acoustics speakers, and, as you may have realised, another result of our sound testings is that we do not favour rounded or tapered ends of port tubes, neither in terms of air movement noise, nor in terms of efficient and precise Helmholtz resonator tuning. Apropos of tuning, the exact length of the ports determines the correct resonant frequency of the port-cabinet-driver system; this tuning is a matter of millimeters, so we devote much time to production of tubes of the right length.