The woofer is a special type of speaker who can play low-mid frequencies of the audio range and is always accompanied by other speakers capable of reproducing the remaining frequencies. Along with the woofer is usually at least a tweeter with the first from a two-way speaker system, capable of reproducing high frequencies and low-mid range acoustics. There are also more complex speaker systems, such as three-way where in addition to the woofer and tweeter are also a midrange able to reproduce the midrange frequencies.
Woofer – Features
Typically, the different speakers are assembled and wired within a single case that takes the name of the speaker. The most popular methods to make best use a woofer in a speaker are the air suspension, the reflex and passive bass reflex, but there are also different.
The woofer has weight and usually larger than the other two transducers. It is of conical shape with a large diameter and, from the point of view electromechanical, is quite robust, provided by a coil, integral with the cone, and of a magnet, capable of ensuring an adequate magnetic flux during the rapid and large axial movements made by the coil itself. The larger sizes of the woofer are easily explained if we consider that a low-frequency range requires a considerable amount of energy in order to get the same sound intensity; think in fact, that in a plant, high fidelity the woofer arrives to dissipate, albeit for brief moments, even kilowatts of energy during rapid transient sound.
The cone of which is composed of this transducer is generally made of paper, carbon alloys, plastic resins or metal alloys. Like all the woofer, transducer also has a very light and very rigid membrane and considering the large size of the cone will be evident how difficult it is to get this feature. In the woofer cone rigidity of the best quality is achieved by building the cast-aluminum basket getting a transducer weighing ten kilograms.
Type of Woofer Speaker
There are particular types of such as full-range woofer because axially incorporate a midrange and a tweeter, are best known by those of English Tannoy. Since there are no regulatory or standards for the classification of these speakers, woofers are defined, improperly, even small transducers such as those contained in the coffers of mp3 players and computers.
Not all woofers on the market have a conical shape, such as the American Magnepan speakers and for its type, isodynamic uses transducers (woofers and midrange, in particular) to flat sheet membranes made of mylar (plastic). On these through a process of metallization is realized the coil. The transducers are placed between the permanent magnets and have a function similar to that of a classic configuration with speaker cone.