Audio Engineering

682 Chapter 23 The term Ka has special signifi cance: it relates the diaphragm radius to the wavelength of sound at any particul ...

Loudspeakers 683 mass of gas contained in a constriction that is short enough so that all particles are assumed to move in phase ...

684 Chapter 23 The beauty of the analogue method of analysis is that it is possible, by using various transformation equations, ...

Loudspeakers 685 23.8 Diaphragm/Suspension Assembly ........................................................................ Ass ...

686 Chapter 23 Figure 23.8 shows the necessary peak amplitude of a piston mounted in an infi nite baffl e to radiate one acousti ...

Loudspeakers 687 over wavelength. This shows the degrees off the normal axis at which the attenuation is 3, 6, 10, and 20 dB (as ...

688 Chapter 23 If instead of a straight-sided cone, the profi le is curved, the “ smoothness ” of the overall response can be im ...

Loudspeakers 689 The conical diaphragm also has radial or “ bell ” modes of fl exure. These are similar to the resonances in a b ...

690 Chapter 23 modes and decrease stiffness for the concentric modes. By correctly proportioning the number, width, and wall thi ...

Loudspeakers 691 interference patterns that result in some cancellation of the emitted sound in the mid upper frequencies, say 8 ...

692 Chapter 23 23.14 Suspensions The purpose of suspensions is to provide a known restoring force to the diaphragm/voice coil as ...

Loudspeakers 693 woven materials, these must be sealed and the sealant is usually used to provide some mechanical termination of ...

694 Chapter 23 Fortunately, there is in-built semiprotection for the assembly, namely temperature coeffi cient of resistance of ...

Loudspeakers 695 either inward or outward depending on the direction of the current. The magnitude of this force is FBli Newton ...

696 Chapter 23 This represents a simple series resonant circuit shown in Figure 23.15. While one can predict resonant frequency ...

Loudspeakers 697 23.17 Motional Impedance ...................................................................................... ...

698 Chapter 23 where Yem is electrical admittance due to mechanical circuit G R B em em em electrical conductance electrical s  ...

Loudspeakers 699 and the mechanical impedance Zm will have a minimum value  Rm. The velocity will be maximum, thus the back EMF ...

700 Chapter 23 Figure 23.17 shows that the inductance of the voice coil is refl ected into the mechanical circuit as a complianc ...

Loudspeakers 701 LCBlcm md^22 Henries (23.41) R Bl em Rem  Ohms 22 (23.42) Rc and Lc are the “ blocked ” impedance values and ...