Speaker cones vary in size and shape as well as the material they are made of. They range from original Rice and Kellog design-paper cone, through Kevlar and carbon fibre, metal (aluminium) and a variety of composites, each manufacturer employing different materials suited to providing the best efficiency and linearity. First of all they wanted to achieve manufacturing consistency since wood is not a homogenous substance and tends to vary from one form of timber to another, even one batch of the same timber to another. At this point it is worth mentioning the phenomenon of wood pulp cones. Even though it seems hard to keep manufacturing consistency “a lot of experienced guitar players claim to hear their instruments more clearly through paper cones in contrary to plastic ones”( Holland, Newell, 2007, p.28)
Organic cones have another great advantage over other types – they maintain high rigidity and high damping factor which is impossible with synthetic cones – one tends to reduce the …show more content…
The chassis
The prime function of the chassis is to provide a frame so magnet and suspension systems can be attached. Whether this is made of plastic or metal is a decision strictly limited by the RMS power that the speaker can handle. High power performance can create heat of around 250°C(Langford-Smith, 1957, p. 835) hence the need for a metal chassis. It helps to dissipate heat and is sufficiently stiff. Another choice has to be made in choosing a stamped or cast metal basket. The latter tends to be more precise and maintains its stability. Aluminium cast frames are usually chosen for large woofer cones which have to deal with heavy magnets.
On the one hand, the chassis has to be as strong as possible but on the other hand it must not influence speaker cone movement. Therefore it needs to be as open and durable as possible. Well-vented design assures heat radiates away from the voice coil. The last factor is self-resonance. To counter this the chassis has to be acoustically dampened.
1.6. Voice coil …show more content…
The front and rear part of a cone are totally out of phase to each other. Without an enclosure they would cancel one another out greatly, especially lower frequencies which are more omnidirectional. Hence we need to make sure that waves created from behind won't interfere with those at the front. How can this problem be solved? The perfect solution is to place the speaker in a large rigid board or a wall. In an ideal world it would be infinitely large to avoid front-to-back cancellation. Practically, this is obviously quite hard to achieve here on earth so we tend to put a driver in a sealed box