Index

A.D.A.M Audio, 50, 52

ABR (Auxiliary Bass Radiator), 81

Absolute phase, 291

Acausal responses, 220, 224–5, 376

Acoustic centre, 276, 295

Acoustic impedance, 7, 99, 196

Acoustic labyrinths, 76, 77

Acoustic lenses, 117

Acoustic Research, 71

Acoustic source plots, 274, 289, 292–3, 315

Acoustic suspensions, 71

Acoustical Manufacturing Company, 271

Air conditioning, 246

Air, weight of, 1

Alnico, 22, 37

Amplifier classes, see Biasing class

Anechoic chambers, 196–7, 376

Angus, Professor James, 394

Antinode, 210, 211, 236, 303, 368

Aquaplas, 28

ATC SCM10, 252, 325

Audibility of phase (rate of change of), 155

Auditory nerves, 153

Auratone 5C, 232, 255, 297, 327, 329, 334

AX1, 112

AX2, 110, 112–13, 118, 121

Axis tilting, 128

Back-EMF, 171, 173, 377

Baffle:

finite, 65

general, 65

infinite, 65, 88

open, 65

Bailey, A. R., 78, 80

Bailey, Mark, 319

Bandpass enclosures, 82, 365–6

Bass-guitar/bass-drum balances, 279, 290, 301, 330, 339, 350

Bass management, 361, 363–4

BBC, 27, 168, 257

Belendiuk and Butler, 306

Beryllium, 43, 47, 244

Bessel filters, 137

Bextrene, 27

Bi-wiring, see Multi-cabling

Biasing class, 158

Bipolar junction transistors (BJTs), 163, 164

Bipole radiators, 355–6

Bl non-uniformity, 282–3

Blauert and Laws criteria, 295

Blumlein, Alan Dower, 216

Bookshelf loudspeakers, 92–3, 338, 377

Boyle's law, 324

Bradbury, L. J. S., 80

Break up, 24, 43, 282

Briggs, Gilbert, 3, 274

Brownian motion, 271

Butterworth filters, 68, 137

Cabinet, construction of, 87

Cabinet lining materials, 76–7, 86–7

Cabinet tuning, 72, 81

Cables, gauge of, 167

Cables, length of, 167–8

Campbell, Alex, 146

Capacitance of cables, 168

Causal responses, 225, 377

Celestion loudspeakers, 28, 267

Centre-front channels, 360–1, 372–3

Centring device, 23, 25–6

Cepstrum analysis, 118, 289, 295–7

Characteristic impedance, 101, 239

Cinema sound systems, 357–60

Class A, 159–61, 163, 180–1

Class A Sliding bias, see Sliding bias Class A

Class AB, 161, 163, 181

Class AG/AH, 163, 245

Class B, 160

Class C, 161

Class D, 161–3

Class G, 163

Class H, 163

Close-field, 13, 248–9, 258, 332, 378

Cobalt, 37

Colloms, Martin, 28, 87, 188

Colouration, 51, 56, 87, 118, 218, 263–4, 267–9, 276, 282, 304, 329, 373

Comb filtering, 99–100

Compact disc, 259

Compensation networks, 154

Compression drivers, 45, 160

Compression ratio, 45, 101

Computer aided design, 246

Concise Oxford Dictionary, 347

Cone profiles, 266–7

Cone sag, 33

Cones, solid, 25

Congo, 22, 37

Conjugate networks, 138

Constant voltage sources, 166–7, 326

Converters–D to A, A to D, 147, 149, 162, 189, 194, 223, 301–2, 377–8

Critical damping, 67

Critical distance, 249, 332

Crossover distortion, 160–1, 245, 282

Crossover points, choice of, 242

Crossovers:

active, 124, 142–3

digital, 146–7

first-order, 131, 142

fourth-order, 136, 142, 243

high-order, 136–7

inductive, 124

inductor/capacitor, 129–30

Linkwitz-Riley, 136, 142, 243

mechanical, 124

passive, 124, 142, 145, 154, 164, 173, 246–7, 335–6

phase response of, 134–7

reconstruction problems, 125, 226, 299

resistor/capacitor, 130

second-order, 133

third-order, 134

Crowhurst, N.C., 274

Current sheet, 49–50

Cut-off frequency, see Horns loudspeakers

Czerwinski, Eugene, 174, 283, 288

Damping, 70, 87, 172, 269, 378

Damping factor, 167–8

d'Appolito layout, 243

DCW (Directivity Control Waveguide), see Waveguides

Deadsheet, 87, 362, 378

Decibel, 379

Delta function, 272, 274, 278, 288–92

Deutsch, Dr Diana, 306

Diffracted waves, 90

Diffraction:

effects, 88, 262

horns, see Horns loudspeakers

sources, 88–9, 92

Diffusers (acoustic), 242, 355

Digital response correction:

of loudspeakers, 220, 301

of rooms, 226, 298–9

Dipole radiators, 59, 200, 210, 355–6, 374

Dirac function, see Delta function Dirac, Paul, 292

Directivity, 102, 241–3

Directivity factor (Q), 198

Directivity index (DI), 198

Disc cutting, 258

Distributed mode loudspeakers (DMLs), 51, 53, 55–6, 61, 355

Dither, 189

Dolby, 352–3, 363, 374

Dolby Digital (Surround), 363, 373

Dolby EX, 357

Dolby Stereo, 353

Dome loudspeakers, 40, 121

Domes:

hard, 43

rigid, 43, 248

soft, 43, 248

Doppler distortion, 107, 326

Double distance rule, 201, 207

Driver stages, 164

Drone cones, see ABR (Auxiliary Bass Radiator)

Dynamic Class A, 161, 245

Dynamic impedance, 246

Efficiency, see also Electroacoustic efficiency; Radiation efficiency

Electrical protection filters, 327–8, 342, 347

Electroacoustic efficiency, 10, 96, 101, 391

Electromagnetic interference (EMI), 162

Electrostatic loudspeakers, 58–63, 151, 200, 210

EMI (the EMI company), 216

Emilar EK175, 118

Equal loudness contours, 235

Equalisation, one-third octave band, 225, 233

Excess phase, 226, 299, 343

Fahy, Professor Frank, 1

Ferrofluids, 39, 44

Fidelity – definition of, 347

Field coil, 22

Figure-of-eight radiators, see Dipole radiators

Flare discontinuities, 104, 109, 118

Flare rate, 97, 121

Flare shape, 97

Fletcher-Munson curves, 270, 348

Flush mounting, 88, 91, 211, 233, 254, 261

FM Acoustics, 247

Fosgate, James, 355

Fourier, 292

Fourier transform, 225, 292, 381

Frequency-band splitting, 164–5, 188, 192

Frequency—definition of, 213, 382

Frequency response:

full, 157, 272, 275

magnitude of, 156, 272

plots, 275

Frindle, Paul, 189–90

Genelec, 120, 220–2, 280, 358

Gerlack, 48

Glaser, Ronald, 190

Grille losses, 92

Group delay, 128, 146–7, 220, 226, 274, 293–5, 299, 382

Guitar amplifiers, 267, 282

Haas effect, see Precedence effect

Hair cells, damage to, 250

Harmonic distortion, 157–8, 272, 281, 283

Heaviside function, see Step-function

Heaviside, Oliver, 154, 292

Height—apparent perception of, 307

Heil air-motion transformer, 50, 52

Heil, Dr Oskar, 51

Hemi-anechoic chambers, 196, 197, 382

Heron, Dr Ken, 51

Heyser, Richard, 271

Hitachi, 163

Holman, Tomlinson, 354–5, 360, 369

Hooke's Law, 34

Horns loudspeakers:

catenoidal, 121–2

conical, 97, 99

constant directivity, 104

cut-off frequency, 99–100, 108, 122

diffraction, 119

exponential, 98, 100, 103

folded, 123

general, 19, 45, 96, 243

hyperbolic, 121–2

hypex, 121

low frequency, 113, 365–7

materials of construction, 119–20

multicellular, 119–20

radial/sectoral, 103, 118–19

vestigal, 120

Human hearing system, 271

Hysteresis, 34, 43

Impedance, 7, 9, 159, 382

Impedance analogy, 13, 16

Impulse, see Delta function

Inductance of cables, 167–8

Inductive coupling, see Crossovers

Infinite baffle, see Baffle; Sealed box loudspeakers

Inner suspension, 23

Instantaneous current capacity, 158

Institute of Sound and Vibration Research (ISVR), 112, 146, 306

Intermodulation distortion, 29, 47, 157–9, 164, 192–3, 273, 283, 288

Ionic loudspeakers, 57

Isobaric loudspeakers, 84

ITU775, 358–9

JBL, 117, 221, 280, 291, 357

JBL L100, 26

JDF, 247

ka, 10

Karlson Coupler, 268

Katz, Dr Shelley, 55

KEF, 33, 55–6, 87

KEF Uni Q, 128, 131

Kellogg, E., 2, 39

Kelly, Stanley, 49

Kinoshita monitors, 145

Kinoshita, Shozo, 247

Korg, 56

Krell amplifiers, 164

Laplace, Marquis de, 292

Lateral reflexions, 304

Layered Sound, 55–6

Leslie tone-cabinet, 151

LFE, 363

Linear distortion, 157, 264, 276

Linear system, 3, 272

Lining materials, see Cabinet lining materials

Litz wire, 170, 188, 193

Live-End, Dead-End rooms, 218

Lodge, Sir Oliver, 2

Loudspeaker:

basic groupings, 229

definition of, 1

orientation of, 219

power ratings, 153

sensitivity/efficiency, 246, 330

Low frequency alignments, 68, 75, 81, 243, 263, 320, 338, 347–8

Magnetic gap and coil proportions, 265

Marginal stability, 168

Marshall amplifiers, 267

Masking of detail, 342

Mastering, 258–63, 276, 279–80, 319, 329, 339, 345, 349

Meter bridge (console top) mounting of loudspeakers, 92, 253, 334, 338

Meyer HD2, 121

Mid-field monitors, 258

Minimum audible field, 348

Minimum-phase responses, 140, 220–1, 224–6, 275, 299, 384

Mirrored room analogy, 205

Mobility analogy, 13

Mode, see Resonant mode

Modulation transfer function (MTF), 222, 297–302, 345–50

Mongoloid races, 306

Monopole sources (radiators), 210, 374

MOSFET, 163–4

Motional feedback, 226

Moulton, David, 271, 308

Moving coil cone loudspeakers, 9, 22, 39

Multi-cabling, 191, 193, 247

Multi-tone testing, 174, 286–8

Multiamplification, 192–3, 247

Mutual coupling, 205, 215, 386–7

Near-field, 12, 248–9, 387–8

Negative feedback, 170, 183, 269

Neodymium magnets, 23, 37

New Transducers Ltd, 51

Node, 210, 303

Noises:

from equipment (physical), 224

in signals, 157

Non-environment rooms, 218

Non-linear distortion, 47, 157, 162, 174, 230, 239, 264

Non-linear system, 272, 285, 323, 388

Non-minimum-phase responses, 140, 146, 220, 223–6, 384

Norcross, S. G., 223

NXT, 51

Off-axis energy, 242, 276, 296, 373

Ohm's law, 14

Olson, H. F., 49, 88

Oxygen-free copper (OFC), 180

Pan-pot, 215–16

Parasitic cones, 124, 127

Particle velocity, 7, 51

Passive radiator, see ABR (Auxiliary Bass Radiator)

PCM, 162

Pedestal mounting, 338

Pendulum, 208

Perception relative to SPL, 231, 251

Permendur, 37

Phantom images, 212, 215–17

Phase, 274, 277, 289, 297, 327, 329

Phase dispersion, 11

Phase distortion, 156, 226

Phase inverters, see Reflex enclosures

Phase shift, 156–7

Phase slope, 156

Phasing plug, 47–8, 115

Piezoelectric transducers, 57

Pink noise, 292, 390

Pinnae, 303, 305, 307, 390

Piston radiators, 99, 239, 243

Planar loudspeakers, 63

Plane wave, 7, 104

Plates, vibrations in, 282

PMC (Professional Monitor Company), 78, 260

Polyamplification, 192–3

Power amplifier, 151, 237

Power cables, 246

Power ratings of amplifiers, 154

Precedence effect, 217, 372, 390

Pressure source, 210

Progressive wave, 7, 104

Pulsating sphere, 40

PWM, 162

Pythagorus’ theorem, 17

Q (directivity factor), see Directivity factor (Q)

Q (quality factor), 65, 68–9, 73, 81, 136, 390

Quad Electrostactic Loudspeaker, 62

Quad ESL 63, 61

Quadrophonics, 352–4

Quartz cells, 57

Quested HM415, 247

Quested Loudspeakers, 358

Radiation efficiency, 96, 99, 101, 239, 325

Radiation impedance, 202, 205

Radio frequency interference (RFI), 188–9

Radiola Model 104, 3

Rare earth magnets, 22–3, 37

Rattles, 157

Reactance:

of capacitor, 12, 16

general, 7

of inductor, 12, 16

Reactive impedances, 7, 171

Reflex cabinets, 71, 200, 260, 326, 328–9

Reflex enclosures, 71

Reflex loading, 71, 239, 326

Resistance, 391

Resonance, free air, 35, 73

Resonant frequency, 87, 239, 324

Resonant mode, 209–10, 236, 303, 366–8, 384–6

Resonant systems, 18, 71, 279, 327

Reverberation chambers, 197, 199, 214, 297

RG59 cable, 174, 180

Ribbon loudspeakers, 48

Rice, C., 239

Ring radiator, 42, 44–5

Robinson-Dadson curves, 235, 270, 348

Rochelle salt, 57

Rocking motion, 44

Roederer, J.G., 308

Roll-offs:

at high frequencies, 233

orders of, 129–37, 328, 339, 341, 343, 347

phase effects, 155

Room equalisation, 298–301

Room modes, see Resonant mode

Samarium magnets, 23, 37

Schottky, 48

SDDS, 357

Sealed box loudspeakers, 65, 67, 76–7, 80, 200, 328–9, 342

Semi-anechoic chambers, 196, 391

Sensation of fidelity, 56, 267

Siemens, Werner, 2

Skin effect, 170

Slew rate, 154

Sliding Bias Class A, 160–1

SLS Loudspeakers, 50

Small, Richard, 123, 139

Solid State Logic, 189–90

Sony Oxford R3, 189–90

Sound, 1

Sound field distortion, 303

Sound fields, 238, 302, 306

Sound power, 96

Sound pressure, 1

Spaciousness, 304

Speaking tubes, 201

Specific acoustic impedance, 7

Speech transmission index (STI), 297, 342, 347

Speed of sound:

in air, 1, 105, 147

in other materials, 147

Sphere, surface area of, 197

Spider, 23, 25, 32–3, 39, 326

Standing waves, 99–100, 209, 392

Step-function, 154–5, 274, 288, 316

Step-function generator, 154, 289, 316

Step response, 128

Stereo, original patent, 216

Stretching pressure, 97–9

Strings, harmonic break-up, 282

Sub-woofers:

compound, 368–9

general, 361–8

mono, 85, 361, 365

multiple, 262, 363

stereo, 85, 361

Sum and difference tones, 273

Super Class A, 160–1

Super position, principal of, 105

Surround loudspeakers (in cinemas), 373

Surrounds (of loudspeaker diaphragms), 30–1

Suspension, inner, see Spider

Tannoy, 143, 152

Tannoy Dual Concentric loudspeakers, 45, 107, 111–12, 115, 128, 134, 244

Target functions, 139–40, 240

TD 2001, 111, 118, 174, 244

Terekhov, Alexander, 174

THD+N, 281

Theile, Neville, 139

Thermal compression, 239, 243, 246, 326

Thomas, Peter, 78

THX, 352, 374

Titanium, 43, 121

Toole, Dr Floyd, 308, 368–9

Toyashima, Sam, 358

Transient headroom, 245

Transient response, 69, 75, 154–5, 164, 225–6, 245–6, 292, 299, 327, 350, 366, 393–4

Transmission lines, 76, 200

Transparency, 286, 301

Tuning ports, 326–7

Turbulence, 116, 326

UREI 815, 252, 325

UREI horns, 128

Valve (tube) amplifiers, 151, 164, 168, 269

Velocity component, 208

Vented boxes, see Reflex enclosures Villchur, Edgar, 71

Voice coil, 22–3, 35, 147, 332

Voice coil former, 35

Voice coil temperatures, 35, 37, 39–40, 332

Voight, Paul, 3

Voishvillo, Alexander, 174, 283

Voltage-controlled amplifiers (VCAs), 189

Volume-velocity sources, 9, 210, 239, 321

Vox AC30, 28, 267

Waste heat, 30, 237, 239, 243, 252, 265, 323, 326, 332

Waterfall plots, 255, 277, 289, 315, 322–3, 332, 344, 346

Watkinson, John, 272, 301

Wattless power, 17

Waveform steepening, 105–6

Waveguides, 92, 115, 120–1, 245

Wavelength, 126, 213

Wedges, anechoic, 196

White noise, 292, 394

Work, 19

X-curve, 235, 358–9

Yamaha NS10M, 92, 164, 232, 253, 255, 279, 327, 329, 334

Zobel filter, 189