Index – Small Signal Audio Design, 3rd Edition

Index

Note: Page numbers in italic indicate a figure and page numbers in bold indicate a table on the corresponding page.

1/f noise (flicker noise) 2021, 2526

2N4403 transistor 288

2N5457 transistor 686

2N5459 transistor 686

2SB737 transistor 28, 28; moving-magnet inputs 258260, 258, 266267, 266; tape replay 303304, 303

3.3 V single-rail operation 176178

4x gain 39, 39, 516519

+5 V supply rail 167176, 176, 178

±15 V power supply 720722

±17 V power supply 723

+48 V phantom power supplies 731732

4000 series analogue gates 580, 580

4016 analogue gates 579583, 581582, 590593, 591593, 653, 685

4066 analogue gates 581585, 583, 585, 587, 587, 591593, 593

7824/7924 integrated circuits 272

AC 8183, 284287, 292293, 721723; MM cartridge DC and AC coupling 255

active balance controls 386387; and Baxandall stage 409

active clipping: feedforward 711713; with opamps 706; transistors 703705

active filters 180, 205

active gain controls 196197; plus passive attenuators 197

active panpot 625627, 626627, 630, 633

active preamplifiers 194, 386, 483

active volume controls 339343

AD797 opamp 128130, 129130, 151, 152, 531, 531532

AD1854 DAC 738

AD1871 ADC 735

AD1974 ADC 735736

AD8022 168; in +5 V operation 171172, 171, 178

AD8397 177178, 177178: in +5 V operation 172176, 176

AFL systems 658

all-pass filters 182

ALPS SPUN switch 575, 630

Ambler concept 424

amplification: moving-coil head amplifiers 281, 283; and the gain-distribution problem 195; quiet 34; strategies 281; see also amplifiers

amplifiers 2; amplifying stages 199204, 206210; CA3080E 688689; component mismatch effects 497500; current 2; dual-gain pot 203204, 209210; an effective MC amplifier configuration 285286; guitar 322; hybrid MM amplifiers 262; hybrid summing 646650; instrumentation 514521, 514, 516, 518, 520521; Johnson noise 1718; limitations 224; line inputs 482; LM13600 689; MM amplifier configurations 227228; moving-coil input amplifiers 283284; multiple 40; Neumann SAL 74B; noise 2223, 280, 572; post-fade 617618; a practical MM amplifier 273278; Radford HD250 196; single-gain pot 199202, 206208; stereo power 52; summing 115116, 643651; switched-gain 211214; tape replay 300301; transconductance 2; transimpedance 3; voltage 2; see also headphone amplifiers; opamps; summing amplifiers

analogue-to-digital converters (ADCs) 733737

attack artefacts 695

attenuation: then amplification 15, 15; quiet 3233

attenuator volume controls 362371

Audio Note cartridge 279

Audio Precision (AP) SYS-2702 measuring system 32, 93, 102, 120121, 138, 149, 351

Augustadt, Herbert 189

auxiliary sends: mixer sub-systems 634

A-weighting 17, 217, 256, 265

bainter filters 190191, 190, 272

balance controls: active 386387; combining balance controls with other stages 388; ideal balance law 381383; mono/stereo switches 391; passive 383385; switched 388390; width controls 392394

balanced cables 487488

balanced connectors 489

balanced-feedback hybrid microphone preamplifier (BFMA) 469

balanced headphone amplifiers 572574

balanced hybrid summing amplifiers 649

balanced inputs: cables and interference 487488; combined line input and balance control stage with low noise 509; combined unbalanced/balanced 504; connectors 489; ground-cancelling outputs 547; high input-impedance balanced inputs 511512; instrumentation amplifier 514522; interconnections 485490; inverting two-opamp 513; MM 263264; practical 501503; self variable-gain line input 510; signal levels 489; superbal input 505; switched-gain 506; variable-gain 507508

balanced interconnections 485; advantages of 486; disadvantages of 487

balanced line outputs 549551

balanced signal levels 489

balanced summing systems 637

band-pass filters 181; multiple-feedback 188

bar-graph metering 678682

Bateman, Cyril 75, 7880

Baxandall, Peter 246, 251253, 253, 344

Baxandall active volume control 344; improved volume stage with lower noise 352353; loading effects 350351; low-noise Baxandall active volume stages 347349; passive control 354355; a practical Baxandall active volume stage 345346; volume control law 344

Baxandall tone controls: combining a Baxandall stage with an active balance control 409; fixed frequency middle controls 425427; impedance and noise 406408; one-LF-capacitor tone control 397402; switched-HF-frequency 410411; three-banded EQ in one stage 428429; two-HF-capacitor tone control 404405; two-LF-capacitor tone control 403

BBC 292, 362, 392, 505, 678, 696

belt-ganged volume controls 359

Benet, Stephen Vincent 719

Bessel filters 179, 182185, 183184, 184, 739

beta (hfe) ratio 88

bias current 131132, 132, 484485

bipolar input opamps 137140

bipolar junction transistors (BJTs) 86, 144; +48 V phantom power supplies 731732

bipolar transistors: current noise 2528; and FETs 86; noise 24; voltage noise 25

Blackmer, David 690

blue noise 17

Boctor filter 191

bootstrapping: collector 106107, 107, 112114, 124125, 124; junction field-effect transistors 476, 593598, 594; supply rail 113

braided screen cables 487488

bridged-differentiator notch filter 190191, 190

bridging impedance 455

broadcast consoles 450451, 652, 698

Brownian motion 17, 478

bus: residual 115116, 115, 636, 645646, 645; trim control 453, 462, 464

Butterworth filters 268269

C1 237245

CA3080E amplifier 688689

cables: balanced 487488; braided screen 487488; mercury 4546; overlapping foil screen 487; ribbon 611613, 635, 649, 658; wiring resistance 46

Cambridge Audio 388; 840A integrated amplifier 371; 840E preamplifier 363, 371; 840W power amplifier 530; P50 integrated amplifier 255, 343

cancellation 272

capacitance: impedance and crosstalk 5253; Johnson noise 1718; PCB track-to-track crosstalk 4952, 4950; resistors 5253, 7375, 499501, 633634

capacitors 7382; blocking 7475, 229230, 502504; capacitor microphone head amplifiers 476477; ceramic 74, 734; decoupling 74, 157, 647, 667, 680, 720724; electrolytic capacitor non-linearity 8082; input sampling 736; leakage 73; non-electrolytic capacitor non-linearity 7579; non-linearity 75; polyester 7679, 76, 77, 187188, 188; polyethylene terephthalate (PET) 75; polypropylene 7475, 270272; polystyrene 7475; properties 7374; reservoir 721727; series 74; tan-δδ (tan-delta) 73

carbon composition resistors 53, 65

carbon-film resistors 53, 6770, 69

cartridges: cartridge–preamplifier interaction 254; cartridge types 215; DC/AC coupling 255; frequency response 253; impedances 226229, 254260, 279282, 285287, 316318; loading 253; load synthesis for lower noise 266267; moving-coil cartridge characteristics 279; sensitivities 223

CAST see Current Audio Signal Transmission

CBS (broadcaster) 676

CD players 191, 195, 217

ceramic capacitors 74, 734

channel modules: group module circuit blocks 634635; in-line 462464; routing 462, 653; split-format 455461

Chebyshev (elliptical) filter 179, 182

circuit block 1516, 614, 634, 674675, 675

clamping 706707

clamping diodes 524, 536, 737

clipping: active clipping with opamps 706; active clipping with transistors 703705; biased diode 702; by clamping 706707; diode 700702, 702; feedforward 711713; negative-feedback 708711; opamps 481482, 518519, 669670, 700701, 706713; soft 322, 662; transistors 9091, 714715

CMOS analogue gates 580; control voltage feedthrough 590; costs 592; current mode 588; at higher voltages 591; at low voltages 591; series-shunt current mode 589; voltage mode 581587

CMRR 545546

collector bootstrapping 125

Colpitts oscillator 9596, 96

Columbia (record label) 215

combined LED indicators 676

combined low-pass/high pass filters 181

combined unbalanced/balanced inputs 504

common-mode (CM) distortion 136142; bipolar input opamps 137140; JFET opamps 141142

common mode (CM) range for opamps 130

common-mode rejection 490492; basic balanced input and opamp effects 495; basic electronic balanced input 493494; line inputs 490495; opamps 495

complementary feedback pair (CFP): configuration 88, 9596, 98, 117; constant-current 88, 9697, 99; emitter-followers 9698, 9697; parametric middle EQs 441; two-transistor series feedback gain 117

component lifetimes in mixer subsystems 666668

components see specific components

compressors 687688

compressors/limiters 691694; attack artefacts 695; combination; decay artefacts 696; subtractive VCA control 697

conductors 4348; cables 46; copper 4345; gold 46; PCB track resistance 4748; properties 44, 44; silver 44, 44; wire resistance 46

Connor, Gareth 649650

consoles: broadcast 450451, 652, 698; cooling in mixer subsystems 666668

constantan 44

control interaction 397, 410, 413, 428, 433

control law: balance controls 389; gain 196197, 201, 209; level control and special circuits 686, 691; microphone preamplifiers 467, 475; mixer sub-systems 617; tone controls and equalisers 409; volume controls 325331, 334339, 341345, 352, 354, 357, 379

control-room monitor (CRM) 452453, 460

cooling: electronic 666; fan 729

copper: balanced cables and interference 488; conductors 45; metallurgy 4546; mixing bus systems 51, 612; moving-coil transformers 44; PCB track resistance 4748; properties 44, 44

correlated noise 531

cost of opamps 132

crosstalk 52; balancing tracks 650651; impedances 52; inductors 83, 488; input-select switching 575577; inter-bus 116, 636

current amplifiers 23

Current Audio Signal Transmission (CAST) 1

current-carrying capacity 46

current feedback amplifiers (CFAs) 2

current-mode connections 1

current-sharing 283, 288

current source: Johnson noise 1718; transconductance amplifiers 117, 689

DC: discrete JFET switching 607; drain resistors 230, 484485, 503, 510; MM cartridge DC and AC coupling 255; potentiometers 359; see also DC blocking capacitors

DC blocking capacitors 74; line inputs 504, 510; line outputs 535; microphone preamplifiers 469, 471, 475; mixer sub-systems 617, 646; moving-magnet inputs 255256, 275; opamps for low voltages 168; signal switching 607; tone controls and equalisers 422; variable gain stages 206

decay artefacts 696

decoupling capacitors 74, 157, 647, 667, 680, 720724

“destructive solo” 660

differential amplifier array 528, 530, 532

differential filters 191

digital domain interface: analogue-to-digital converters 733; interfacing with ADC inputs 735737; interfacing with DAC outputs 738739; interfacing with microcontrollers 740743; nominal levels and ADCs 734; PCB layout considerations 733; typical ADCs 735; typical DACs 738

digital-to-analogue converters (DACs) 23, 180, 191, 733734, 738740

DIN interconnection standard 1, 485, 489490, 494, 547

diode clipping 700702

direct injection 323324

direct outputs in mixer subsystems 619

discrete circuitry and power supplies 727

discrete class-A headphone amplifiers 570

discrete class-AB headphone amplifiers 566569

discrete JFET switching: advantages 593; control voltage feedthrough in 609610; current mode 600602; DC conditions 607; drive circuitry 605; physical layout and offness 606; reducing distortion by biasing 603604; series JFET switch in voltage mode 593598; shunt JFET switch in voltage mode 599; soft changeover circuit 608; voltage mode 593599

discrete opamp design 117121

discrete transistor circuitry 85; beta 88; bipolars/FETs 86; bipolar junction transistors 86; discrete opamp design 117121; high-input-impedance bipolar stages 122125; reasons for use 123; transistor equation 87; see also discrete transistor circuitry (gain stages); discrete transistor circuitry (unity-gain buffer stages)

discrete transistor circuitry (gain stages) 103; one-transistor series-feedback gain stages 103104; one-transistor shunt-feedback gain stages 103; two-transistor series-feedback gain stages 117; two-transistor shunt-feedback gain stages 105116

discrete transistor circuitry (unity-gain buffer stages) 88; CFP emitter-followers 9697; constant-current emitter-follower 92; emitter-follower stability 95; improved unity-gain buffers 98102; push-pull emitter-follower 9394; simple emitter-follower 8891

distortion 555560; biasing 603604; bipolar input opamps 137140; common-mode distortion 136142; JFET opamps 141142; loading 136; opamp internal distortion 135; opamps 133142; operational transconductance amplifiers 688689; Sallen-and-Key filters 187; slew-rate limiting distortion 135; thermal distortion 136

distributed gain control 196, 331

distributed peak detection 674675

distributed summing systems 640642

Dolby HX-Pro 307310

dominant-pole compensation 254, 263

dual-action volume controls 331333

dual-gain pot 203204, 209210

dual supplies from a single winding (power) 726

dynamic range 46

dynamics section 457, 614, 700

E3 capacitor 745

E6 capacitor 237, 745

E12 resistor 745

E24 resistor 745746

E96 resistor 745746

Early, Jim 87

Early Effect 87, 118, 125, 141

Ebers-Moll transistor equation 87

effects return (split-format) 464

efficient LED bar-graph architecture 680682

Einstein, Albert 19

electric guitar see guitar preamplifiers

electrolytic capacitors 910, 7576, 76, 8083, 8082

electrolytic tough pitch (ETP) copper 45

electronic balanced line inputs 490

electronic cooling 666

electronic switching 579

electronic versus transformer balanced inputs 490

electrostatic coupling 488, 670, 730

elliptical filters 270271

emitter-follower (EF) circuits 89; CFP 95101; constant-current 88, 92, 94, 9697, 99, 102; push-pull 88, 9397, 100, 122, 224; simple 8891; stability 95

endstop resistor see under resistors

equalisation 225; mixer sub-systems 612; tape replay 297299

equalisers (EQs): graphic 443448; new type of switched-frequency LF EQ 415; parametric middle EQ 440442; single-gang variable-frequency middle EQ 435438; switchable peak/shelving LF/HF EQ 439; switched-Q variable-frequency Wien middle EQ 438; three-band Baxandall EQ in one stage 428429; variable-frequency HF EQ 412413; variable-frequency HF and LF EQ in one stage 416421; variable-frequency LF EQ 414; variable-frequency middle EQ 433434; Wien fixed middle EQ 430432

equivalent input noise (EIN) 24; discrete transistor circuitry 109, 112; guitar preamplifiers 317321; headphone amplifiers 566, 572; line inputs 515, 522; microphone preamplifiers 468, 475; moving-coil head amplifiers 288; moving-magnet inputs 256261, 265266; tape replay 303; variable gain stages 200

equivalent series resistance (ESR) 73, 283, 667

evaluation boards 734

excess resistor noise 6869, 69

external signal levels 481

fader flip 455

faders 615617; mixer sub-systems 616; linear 361, 457458, 690; short 454, 464; slide 336338, 615, 672

fader-start switches 338

Fairchild μA709 opamp 127

fan cooling 729

feedforward 307, 616, 616, 694696, 696; clipping 711713

field-effect transistors (FETs): balanced summing systems 638; CMOS analogue gates 580, 586, 591, 600; control voltage feedthrough 591; noise gates 698700, 699; see also junction field-effect transistors (JFETs)

filters 179; active 180; all-pass 182; Bainter 190, 190, 272; band-pass 181; Bessel 179, 182195, 739; Boctor 191; Butterworth 182186, 268272; characteristics 182; Chebyshev (elliptical) 179, 182; combined low-pass/high pass 181; differential 191; high-pass 180, 185186; low-pass 180, 182184; multiple-feedback 188; notch 181, 189190; passive 179; pinkening 715717; radio frequency 273; roofing 179180, 482; Sallen-and-Key 182187; state variable 442; subsonic 233234, 268275; subsonic/ultrasonic combination 181, 273; third order 186187, 269270, 374, 455

First Age of Vinyl 180181

First Law of Thermodynamics 19

fixed frequency Baxandall middle controls 425427

flash bus 664665

flicker noise see 1/f noise

foldback 451452, 457, 459, 461

four-layer summing 643

frequency response 610, 554; all-pass filters 182, 395; Bessel filters 182184, 184, 184; Butterworth filters 182184, 183184, 184, 227, 269, 271, 271; cascaded stages 610; electrolytic capacitors 74, 81, 81, 187, 422; equalisation 225227, 303304; high-pass filters 182, 187, 187; MM cartridge 253; moving-coil transformers 281; negative feedback 409410; non-electrolytic capacitors 10, 187; notch filters 189; opamps 182183, 312313, 443445, 496; output transformer 554; RIAA amplifiers 74; Sallen-and-Key filters 182183, 187, 189; ultrasonic filters 184; vinyl 219; violet noise 17

front-of-house (FOH) mixer 451

gain-control elements: history 685; junction field-effect transistors (JFETs) 685687; operational transconductance amplifiers (OTAs) 688; voltage controlled amplifiers (VCAs) 689691

gain-distribution problem 195

gain law: variable gain stages 199203, 201, 203, 206207, 207, 210, 212; volume controls 346, 356

gain stages 199214; one-transistor series-feedback gain stages 103104; one-transistor shunt-feedback 103; opamps 103, 147148, 199200; two-transistor series-feedback gain stages 117; two-transistor shunt-feedback 105116

gain structures 1416; active gain controls 16; amplification then attenuation 14; attenuation then amplification 15; raising the input signal to the nominal level 15

galvanic isolation 84, 487, 489490, 553, 579

Gaumont, Leon 620

Gershwin’s Law (“it ain’t necessarily so”) 43, 91

Gilbert, Barrie 88

gold 4446, 44, 362363

gold plating 46

graphic equalisers 443448; constant-Q 445; LCR filters 83; proportional-Q 445

grey noise 17

green noise 17

groove curvature 220221

ground-canceling outputs 543549

ground-canceling summing systems 638639

ground plane 5051, 611, 634, 734

ground voltages 494, 543544, 548, 638, 642

group modules: circuit blocks 634; split-format 458

guitar preamplifiers: electric guitar technology 311; guitar amplifiers 322; guitar direct injection 323324; guitar effects 322; guitar leads 314; guitar pickups 311; guitar preamplifiers 315321; guitar wiring 313; pickup characteristics 312

headphone amplifiers: balanced 572574; discrete class-A 570572; discrete class-AB 566569; driving headphones 561; driving heavy loads 561; multiple opamps 562563; opamp-transistor hybrid 564565; special opamps 562

heat sinks 25, 54, 566, 570, 722, 729730

heavy loads 40, 155, 283, 407, 520, 554, 561

hi-fi preamplifiers xxv, 325, 395, 599, 621623

high frequency (HF) correction pole 224225, 228, 231233, 232, 236238, 237238, 246248, 273275, 274

high-input impedance amplifiers 122

high-input-impedance bipolar stages 122125

high-impedance inputs 1, 124, 156

high-pass filters 180; Sallen and Key 185186

Hitachi Cable company 45

Hofer, Bruce 180, 560

Holman, Tomlinson 218, 221, 225226, 254, 373374, 379

hybrid microphone preamplifier 468469

hybrid MM amplifiers 262

hybrid summing amplifiers 646648

hysteresis 669

ideal balance law 381383

IEC 98 standard 226

IEC 60098 standard 226

IEC Amendment 226; implementing 233

impedances 52; bridging 455, 512; crosstalk 484485, 536537, 575579, 635639, 650651

in-line channel module (mixer architectures) 462464

in-line mixing architectures 453454

inductance 6567; guitar preamplifiers 311314, 317321; line outputs 554556; moving-coil head amplifiers 279281; moving-magnet inputs 228229, 253257; tape replay 292297, 303305

inductors 8384, 179180, 444445

input: amplifier functions 482; bias current 131; and ground-cancelling outputs 548; high-input-impedance bipolar stages 122125; input-select switching 575576; interfacing with ADC inputs 735737; microphone and line input pads 470; mixer sub-systems 612; moving-coil input amplifiers 383384; offset voltage 131; opamps 118119, 131, 137140, 144, 156165, 229, 495, 513; overvoltage protection 524; sampling capacitors 736738; selector switch 193194, 325, 483; signal and nominal level 15; transformer microphone inputs 466467; see also line inputs; moving-magnet (MM) inputs

input-select switching: mechanical 575576

insert: points 612614, 457, 464; return 458; send 458459, 613614, 619, 643644, 644

integrated circuit volume controls 372

interference 487488

internal signal levels 481

instrumentation amplifier 514522

insulation-displacement connectors (IDCs) 611, 636, 665, 720

integrated circuits (ICs) 21, 32, 360362, 372; volume controls 372

inter-bus crosstalk 116, 636

interfacing with digital domain: interfacing with ADC inputs 735737; interfacing with DAC outputs 738739; interfacing with microcontrollers 740744; nominal levels and ADCs 734; PCB layout considerations 733; typical ADCs 735; typical DACs 738

internal signal levels 5, 450, 481, 490

intrinsic emitter resistance 2425, 89

inversion, quiet 35

inverting two-opamp input 513

I-V converters 3, 738739, 739

JFETs see junction field-effect transistors (JFETs)

Johnson, John B. 17

Johnson noise 1620, 6768; guitar preamplifiers 316317; how to amplify quietly 34; how to attenuate quietly 3233, 33; how to invert quietly 35; line inputs 484485, 505506, 511514; microphone preamplifiers 473475; mixer sub-systems 63637, 639640; moving-coil head amplifiers 282283; moving-magnet inputs 227230, 232233, 256259, 266267; noise in amplifiers 24; noise in bipolar transistors 2528, 27; noise gain 31; noise in JFETs 2930; noise measurements 32; opamps and their properties 131132, 141143; preamplifier architectures 194195; tape replay 300303; ultra-low-noise design with multi-path amplifiers 36, 38, 40

junction field-effect transistors (JFETs) 28, 258; common-mode distortion 141142; control voltage feedthrough in 609610; in current mode 600602; drive circuitry 605; gain-control elements 685687; input types 156165; mixer sub-systems 663664; noise in 2931; opamps and their properties 127129, 129, 143144, 147148; series JFET switch in voltage mode 593598; shunt JFET switch in voltage mode 599; signal switching 603604, 606608; tape replay 305306

larger power supplies 728

Late Effect 87

laws: ideal balance law 381382; sine/sine squared 620621, 620; thermodynamics 19; volume controls 325327

LCD meter displays 683684

leads 314

leakage from capacitors 18, 73, 168

Left-Center-Right (LCR): filters 83, 179180; graphic equalizers 83, 443444; panpots 628629

level control and gain-control elements 685691, 694695

level control and special circuits: active clipping with opamps 706; active clipping with transistors 703705; clipping by clamping 706707; compressors and limiters 692697; diode clipping 700702; feedforward clipping 711713; gain-control elements 685691; negative-feedback clipping 708710; noise gates 698699; noise generators 714; pinkening filters 715717

level indication: combined LED indicators 676; distributed peak detection 674675; LED bar-graph metering 678679; liquid crystal displays 684; Log Law Level LED (LLLL) 213, 672673; a more efficient LED bar-graph architecture 680682; peak indication 670671; plasma displays 683; PPMs 678; signal-present indication 669; vacuum fluorescent displays 683; VU meters 676677

light emitting diodes (LEDs) 653656, 664666, 669671; bar-graph metering 678679; combined LED indicators 676; Log Law Level LED (LLLL) 672673; more efficient bar-graph architecture 680682

limiters 686688, 691700

linear faders 361, 457458, 690

linearity 5354; discrete transistor circuitry 8586, 8891, 9398, 101103, 111112, 121122; level control and special circuits 685, 688690, 709710; line outputs 554555, 564565; opamps and their properties 146147; signal switching 587591; two-transistor shunt-feedback stages 109111

line inputs: amplifier component mismatch effects 497500; balanced cables and interference 487488; balanced connectors 489; balanced interconnections 485487; balanced signal levels 489; combined line input and balance control stage with low noise 509; combined unbalanced and balanced inputs 504; common mode rejection 490495; electronic balanced 493494; electronic v. transformer balanced inputs 490; external signal levels 481; high input-impedance balanced inputs 511512; input amplifier functions 482; input overvoltage protection 524; instrumentation amplifier 514522; internal signal levels 481; inverting two-opamp input 513; low-noise balanced 525530; microphone and line input pads 470; opamp CMRR effects 497; opamp frequency response effects 496; a practical balanced input 501503; self variable-gain line input 510; superbal input 505; switched-gain balanced inputs 506; transformer balanced 523; ultra-low-noise balanced 530534; unbalanced 482484; variable-gain balanced inputs 507508

line outputs: balanced 549551; ground-canceling 543549; heavy loads 523; output transformer distortion 555560; output transformer frequency response 554; quasi-floating 552; transformer balanced 553; unbalanced 535; zero-impedance 536542

line-up oscillators 661663

Linkwitz-Riley electronic crossover 182

Lipshitz, Stanley 13, 230231, 234237

liquid crystal displays 683684

“Listen” facility 461

LM317/337 variable-voltage IC regulators 724

LM338K variable-voltage regulator 728

LM741 opamp 144

LM833 opamp 129, 130, 133

LM3914 integrated circuit 680

LM4562 opamp 148150, 170

LM7815 fixed IC regulator 720, 723

LM7815/7915 fixed IC regulator 720, 723

LM7824 fixed IC regulator 727

LM7924 fixed IC regulator 727

LM13600 amplifier 689

LM13700 amplifier 689

loaded linear pots (volume controls) 328330

loading 136

load synthesis 305

Log Law Level LED (LLLL) 672673

loudness controls 373376

low-impedance design xxvi, 37, 40, 80; filters 182; line inputs 509; line outputs 547; tone controls and equalisers 406, 416, 419; volume controls 325, 356, 379

low-noise: balanced line inputs 525530; Baxandall active volume stages 347349; operational amplifier circuitry 31

low-pass filters 180; Sallen and Key 182184

low voltages: AD8022 in +5 V operation 171; AD8397 in +5 V operation 172175; high fidelity from 167; LM4562 in +5 V operation 170; NE5532 in +5 V operation 169; opamps for 3.3 V single-rail operation 176178; opamps for 5 V operation 169; running opamps from a single +5 V supply rail 167168

LP records 215216

LT1028 opamp 31, 128130, 129130, 133, 498, 531532, 531

LT1083CK variable-voltage regulator 728

magnetic conductors 43

magnetic coupling 263, 486, 488489

MAGNOISE model 317; MAGNOISE2 256, 258, 266

manganin 44

master module (split-format) 459461

master section 451, 453, 455, 653654, 658

Math CAD software 256

MC33078 opamp 129, 130, 133

mechanical switches 575

mercury: cables 4546; properties 44, 44

Metal Electrode Face-Bonded (MELF) resistors 54

metal oxide semiconductor field-effect gates (MOSFETs) 685

metal-film resistors 5354, 57, 65, 70

metering: combined LED indicators 676; distributed peak detection 674675; LED bar-graph metering 678679; LCD meter displays 6836843; Log Law Level LED (LLLL) 672673; a more efficient LED bar-graph architecture 680682; peak indication 670671; plasma displays 683; PPMs 678; signal-present indication 669; vacuum fluorescent displays 683; VU meters 676677

mic/line switch 455, 471

microcontroller and relay supplies (power) 730

microgroove technology 215216, 255

microphone capsules 24, 466, 476

microphone preamplifiers: balanced-feedback hybrid microphone preamplifier (BFMA) 469; capacitor head 476477; microphone and line input pads 470; microphone types 465; padless 471475; requirements 465; ribbon 478480; simple hybrid 468; transformer microphone inputs 466467

microphone transformer 468

middle controls (tone) 424; fixed frequency Baxandall middle controls 425427; single-gang variable-frequency middle EQ 435437; switched-Q variable-frequency Wien middle EQ 438; three-band Baxandall EQ in one stage 428429; variable-frequency middle EQ 433434; Wien fixed middle EQ 430432

Miller compensation 144, 147

mixer architecture 449451; in-line 453454; in-line channel 462464; internal levels 450; performance factors 449; split mixing 452; split-format modules 455461

mixer bus systems 611

mixer sub-systems: active panpot 625627; AFL systems 658; auxiliary sends 634; balancing tracks to reduce crosstalk 650; circuit block 614; component lifetimes 666668; console cooling 666668; direct outputs 619; equalisation 612; faders 615616; flash bus 664665; group module circuit blocks 634; inputs 612; insert points 612613; LCR panpots 628629; line-up oscillators 661663; mixer bus 611; panpots 619629; passive panpots 621624; PFL systems 652657; post-fade amplifiers 617618; power supply protection 666; routing systems 630633; solo-in-place systems 658659; summing amplifiers 643649, 651; summing systems 635642; talkback microphone amplifiers 660

Molly guard 660

monitor mix 451452, 454, 458459, 464

monitor mixer 451

mono/stereo switches 391

motorised potentiometers 360361

moving-coil (MC) head amplifiers: amplification strategies 281; cartridges 279; complete circuit 287; effective MC amplifier configuration 285286; input amplifiers 283284; limits MC noise performance 280; performance 288290; transformers 281282

moving-magnet (MM) inputs: amplifier configurations 227228; balanced MM inputs 263; calculating the RIAA equalisation components 230; cartridge load synthesis for lower noise 266267; cartridge sensitivities 223; cartridge types 215; equalisation 225; hybrid MM amplifiers 262; IEC Amendment 226; implementing the IEC Amendment 233; implementing RIAA equalisation 230232; maximum signal levels from vinyl 219222; MM cartridge DC and AC coupling 255; MM cartridge-preamplifier interaction 254; “Neumann Pole” 227; noise in balanced MM inputs 263264; noise measurements 265; noise in MM RIAA preamplifiers 255261; noise weighting 265; opamp input stages 229; open-loop gain and RIAA accuracy 249; overload margins and amplifier limitations 224; passive and semi-passive RIAA equalisation 249252; a practical MM amplifier 273278; RIAA optimisation 237245; RIAA series-feedback network configurations 234236; spurious signals 216217; subsonic filters 268272; switched-gain MM/MC RIAA amplifiers 248; switched-gain MM RIAA amplifiers 246247; ultrasonic filters 273; vinyl medium 215; vinyl problems 218

Mr Spock (Star Trek) 50

multi-function summing amplifier 651

multi-path amplifiers and ultra-low-noise 3639

multiple amplifiers 40

multiple-feedback band-pass filters 188189, 189, 662, 665

multiple-feedback filters 190191, 739740

multiple voltage controlled amplifiers (VCAs) 691692, 692

multi-track recording 294

mu-metal 181, 281

mute bloc 602607, 602606

mutual shutdown circuitry and power supplies 729

mutual-shutdown facility 728, 728

NBC (broadcaster) 676

NE5532/5334 opamp 144155, 169; AD797 151; LM4562 148150; OP27 151152; OP270 153154; OP275 155

negative feedback (NFB) 24; clipping 708710; discrete transistor circuitry 117121; level control and special circuits 710711; line inputs 494495; line outputs 536537, 541542, 558559; microphone preamplifiers 469; mixer sub-systems 656657; opamps and their properties 141142

negative-impedance-converter 625

“Neumann pole” 227

Neumann SAL 74B amplifier 227

Newcomb and Young loudness control 377380

nickel 46, 55, 68

NJM4556 opamp 129130

NJM4556A opamp 562

noise: a-weighting 17, 217, 256, 265; active gain control 196198, 339, 347, 353356; amplifiers 2223, 3639; in balanced MM inputs 263624; bipolar transistors 24; blue 17; cartridge load synthesis for lower noise 266267; correlated 531; description 16; discrete class-AB headphone amplifiers 572; excess resistor 6869; flicker 20; gates 698699; generators 714; green 17; grey 17; improved Baxandall active volume stage with lower noise 352353; junction field-effect transistors 2930; limits on MC noise performance 280; measurements 265; in MM RIAA preamplifiers 255261; opamps 2930; pink 17, 714716, 716; red 1617, 714, 717; replay noise 302304; resistor excess noise 6769; routing systems 631633, 631, 633; send amplifier 547; summing systems 619, 637638, 640, 642; violet 17; weighting 265; white 1619, 714717, 715716; see also Johnson noise; noise (gain)

noise (gain) 16, 31; in amplifiers 2223; balanced output 551; bipolar transistor current noise 2528; in bipolar transistors 24; bipolar transistor voltage noise 25; in JFETs 29; noise reductions systems 305306; opamps 29, 128

noise figure (NF) 24, 2728, 28, 7480; filters 187188; moving-coil head amplifiers 287288; moving-magnet inputs 237246, 238, 242, 242, 243, 244245, 261262; tape replay 303304

noise gates 698699

noise measurements 32

nominal levels and ADCs 734

nominal signal levels 46

non-conductors 44

non-electrolytic capacitor non-linearity 7579

non-linearity: capacitor 75; electrolytic capacitor 8082; non-electrolytic capacitor 7579; resistor 7072

normalling contacts 316, 455, 464, 612

notch filters 181, 189190

offness: discrete JFET switching 606; faders 616617; level control and special circuits 698699; mixer sub-systems 624627, 630634, 638639; signal switching 575577, 583588, 590591, 599602, 604605; volume controls 327328, 338339

Ohm, George Simon 43

Ohm’s Law 13, 43, 55, 70, 499

one-capacitor LF control (Baxandall tone controls) 397402

one-ounce copper 47

one-transistor: hybrid summing amplifiers 646; series-feedback gain stages 103104; shunt-feedback gain stages 103

OP27 opamp 151152

OP270 153154

OP275 155

OPA604 162

OPA627 163166

OPA2134 160161

opamps (operational amplifiers) 127; for 3.3 V single-rail operation 176178; for 5 V operation 169175; active clipping 706; AD797 151; AD8022 171; AD8397 172175; bias current 131; BJT input 144; CMRR effects 497; common mode range 130; common mode rejection 495; cost 132; discrete 117121; distortion 133142; frequency response effects 496; high fidelity from low voltages 167; history 127; input 118119; input offset voltage 131; JFET input 156166; Johnson noise 1718; line inputs 495497; LM741 144; LM4562 148150, 170; MM input stages 229; multiple 562563; NE5532/5534 144155, 169; noise 128; OP27 151152; OP270 153154; OP275 155; OPA2134 160161; OPA604 162; OPA627 163166; opamp-transistor hybrid amplifiers 564565; running opamps from a single +5 V supply rail 167168; Sallen-and-Key filters 187; selection 143; slew rate 129; special 562; supply rail voltages 719; TL052 158159; TL072 156157; see also opamps (distortion); specific opamps by name

opamps (distortion) 133134; bipolar input 137140; common-mode 136142; internal 135; JFET 141142; loading 136; slew-rate limiting 135; thermal 136

OP27 opamp 129130, 133, 151152, 152153, 497, 498

OP270 opamp 129130, 133, 153154, 154

OPA604 opamp 129130, 133, 162163, 258, 261

OPA627 opamp 129130, 132, 133, 163164, 498

OPA2134 opamp 128, 129130, 133, 143144, 160162, 164; guitar preamplifiers 317319, 318319, 321322; line inputs 496, 498; moving-magnet inputs 258, 261, 266; signal switching 586, 607; tape replay 303, 304, 305

open-loop gain: and RIAA accuracy 249

Operational transconductance amplifiers (OTAs) 2; gain-control elements 688689

oscillators 461, 661663

OTAs see Operational transconductance amplifiers (OTAs)

overlap penalty 356358

overlapping foil screen cables 487488

overload margins 224

padless microphone preamplifiers 471475

palladium/silver (PdAg) 55

panpots (panoramic potentiometers) 619620; active 625627; full-width LCR 628629, 628; half-width LCR 628629, 629; law bending 623, 625; laws 620628; Left-Center-Right (LCR) 628629; mixer sub-systems 619629; negative-impedance-converter 625626; passive 621624; sine/sine squared laws 620621, 620

parametric equalisers 440442

parametric middle EQ 440442

passive attenuators 197

passive balance controls 383385

passive control: Baxandall active volume stage 354355

passive filters 179

passive panpots 621624

passive preamplifiers 193

passive/semi passive RIAA equalization 249252

passive tone controls 396

PCB track-to-track crosstalk 4950

PCM1802 stereo ADC 735

PCM1794A stereo audio DAC 738

peak detection, distributed 674675

peak indication 670671

peak program meters (PPMs) 678

performance: discrete class-AB headphone amplifiers 572; MC head amplifiers 280, 288290; mixer architecture 449; ripple 725

Perpetual Motion Machine of the Second kind 19

PFL systems 652657

PGA2310 integrated circuit 372

phantom power 731732

phase perception 1113

phono connectors 486, 489

pickups 311; characteristics 312

pinkening filters 715717

pink noise 17, 714716, 716

plasma displays 683

platinum 4445, 44

polyester capacitors 78, 187188, 188

polyethylene terephthalate (PET) capacitors 75

polypropylene capacitors 79, 79, 188, 270272, 422

polystyrene capacitors 78, 78, 241, 275

popcorn noise 20

post-fade amplifiers 457458, 674; mixer sub-systems 616618

post-fade sends 452, 457, 617, 619

potentiometers: DC 359; motorised 360; see also panpots

power consumption: discrete class-AB headphone amplifiers 572

power supplies: ±15 V 720722; ±17 V 723;+48 V phantom 731732; discrete circuitry 727; dual supplies from a single winding 726; larger 728; microcontroller and relays 730; mutual shutdown circuitry 729; opamp supply rail voltages 719; protection 666; ripple performance 725; variable-voltage regulators 724; very large 729; “wall-wart” 726

power supply rejection ratio (PSRR) 719720, 720

PPMs see peak program meters (PPMs)

practical balanced inputs 501503

practical MM amplifier 273278

preamplifiers 193198; active 194; active gain control 196197; amplification 195; architecture 193198; evolution 194, 195; gain-distribution 195; hybrid microphone 468469; LM7824 727; microphone 465, 468469, 471475; MM cartridge–preamplifier interaction 254; noise in MM RIAA preamplifiers 255261; padless microphone 471475; passive 193; passive attenuators 197; recording 197; tone controls 197198; tone-control stage 180; see also guitar preamplifiers; microphone preamplifiers

Precision Preamplifier 225, 236, 246, 346347, 346, 409, 416

pre-fade listen (PFL): AFL 658660; channel module (split format) 653654, 658, 666; detection 654, 656657; master module 452, 457, 459, 461, 660; peak indication 670672; simple 656; split mixing 452; summing 654; switching 654; systems 652657; virtual-earth detection 656657

prefade sends 457

printed-circuit boards (PCBs): digital domain interface 733; layout 733; mixer bus systems 611; Signal Transfer Company 275; three-layer 51; track current capacity 48; track resistance 4748; track-to-track crosstalk 4950

Progressive Electronics 440

protection diodes 584, 722723, 722

psychoacoustic weighting 265

public address (PA) 180, 451452, 468, 552, 660, 667, 729

push-pull: CFP emitter-follower 9697, 100; CFP follower 100; emitter-follower 9394

quasi-floating line outputs 552

quiet amplification 34

quiet attenuation 3233

quiet balance 36

quiet inversion 35

Radford HD250 amplifier 196

radio frequency (RF): field strengths 554; filters 179180, 193, 227, 483

rail bootstrapping 106109, 107109, 113116, 123125, 584

RCA connectors 486, 489

RCA Victor (record label) 215

recording facilities 197

Recording Industry Association of America/RIAA: accuracy 249; amplifiers 246248; differential amplifiers 527; moving-magnet input stages 229; noise in preamplifiers 255261; overload margins 224225; preamplifiers 255261; series-feedback network configurations 234236; signal levels from vinyl 216217, 219222; see also Recording Industry Association of America/RIAA (equalisation)

Recording Industry Association of America/RIAA (equalisation): amplification 15, 224, 250, 281; Audio Note cartridge 279280; cartridge–preamplifier interaction 254; components 230; curve 219, 226227, 231, 250; implementing 230232; input signals 15, 229; inverse 221, 250, 270; noise in preamplifiers 255261; non-electrolytic capacitors 7475, 233, 270; optimisation 237245; passive/semi passive 249252; subsonic filters 270

red noise 1617, 714, 717

relay supplies 730

relay-switched volume controls 371

relay switching 579

reservoir capacitors 696, 721724, 726

resistances and Johnson noise 1619, 2434, 6768; guitar preamplifiers 316317; line inputs 505506, 511512; moving-coil head amplifiers 282283; moving-magnet inputs 256257; preamplifier architectures 194195

resistors 5372; accuracy 5762; carbon composition 53, 53, 65, 6970; carbon-film resistors 5354, 53, 65, 6770, 337; combinations 5763; common-mode rejection ratio 485, 492, 495, 497, 535, 650; end stop 399400, 418, 433, 508509; excess noise 6769; imperfections 67; MELF 54; metal-film 5355, 53, 57, 65, 68, 7071, 634; metal oxide 5354, 53, 68; noise 6769; non-linearity 7072; series 56; surface-mount 5455; switched attenuators 362; temperature coefficient 53, 53, 55; thick-film 5455, 6872, 499; thin-film 5355, 65, 68, 7273; three-resistor combinations 62; through-hole 54; tolerances 5966, 7374, 238244, 342343, 362364, 491492, 498500, 507508; two-resistor combinations 5761; uniform distribution 66; value distributions 6465; voltage coefficients 5355, 65, 7071, 73; wirewound 5354, 56, 68, 70

return-to-flat (RTF) tone-control 416, 418, 440

RF filtering 180, 482483, 487, 502, 517

ribbon cable 611, 613, 635, 639, 658

ribbon microphone amplifiers 478480

ripple performance (power supplies) 725

roofing filters 179180, 482

routing systems: back grounding 630631; matrix 633; mixer sub-systems 630633; offness 630633; panpots 630

rumble 181, 217, 226, 271272

ruthenium oxide 55

safe-operating-area (SOA) 731

Sallen and Key filters: capacitor microphones 476; distortion 187188; high-pass 185186; low-pass 182184; subsonic filters 268, 273

Schlotzaur configuration 88, 98, 101

screening 281282, 487488

‘sea of micro-diodes’ 43

Second Law of Thermodynamics 19

series-feedback: one-transistor 103104; two-transistor 117; RIAA 234236; see also individual circuits

servo integrator 470, 699

short fader 454, 464

shot noise 19

shunt-feedback: one-transistor 103; two-transistor 105116; see also individual circuits

Shure M75ED 2 cartridge 256, 265, 267

sidechain 693697

signal-present indication 669

signals 1; balanced signal levels 489; external signal levels 481; internal signal levels 481; maximum signal levels from vinyl 219222; nominal signal levels and dynamic range 45; raising the input signal level to the nominal level 15; signal-present indication 669; spurious 216217; warping 216217; see also signal switching

signal switching: electronic switching 579; input-select switching 575576; mechanical switches 575; offness 606; relay switching 579; virtual contact 577578; see also CMOS analogue gates; discrete JFET switching

signal-to-noise 45, 3233

Signal Transfer Company 273, 275, 277, 288, 530

silver 4344, 44, 362363

simple emitter-follower (EF) discrete circuit-block 8893, 9698, 123124

simple hybrid microphone preamplifier 468

sine laws 389, 389, 625

sine-squared laws 620

sine/cosine characteristic 381382, 385, 620621

single-gain pot 199202, 206208

single-gang sweep middle tone controls 435

single-gang variable-frequency middle EQ 435437

single-jack insert 612613, 613

“slate” facility 461

slew limiting 130, 135, 144145, 179, 217, 250

slew rate 129; slew-rate limiting distortion 135

slide faders 336338

soft clipping 322, 662

solo-in-place systems (SIP) 658659

Soundcraft 3200 recording console 458, 650

SPICE simulation 91, 9798, 248249

splitter box 451, 554

split-format modules: channel 455457; effect return 458; group 458; master 459460; oscillators 461; talkback 461

split mixing (mixer architecture) 452

spurious signals 216217

Star Trek 50

state-variable filters 181, 191

stepped volume controls 361

stereo image 325, 327, 381, 392, 452

stereo power amplifiers 52

stylus acceleration 220221

subsonic filters/filtering 268272

subsonic/ultrasonic filters combination 181, 273

subtractive VCA control 697

summing amplifiers 643645; balanced hybrid 649; hybrid 646648; multi-function 651; two-transistor shunt-feedback stages as 115116

summing noise sources 21

summing systems: balanced 637; bus residual 636, 645; distributed 640642; four-layer 643; ground-canceling 638639; noise; three-layer 611, 642643, 643; two-layer 640643; virtual-earth summing 635636; voltage summing 635, 636; see also summing amplifiers

superbal input 505

supply-rail voltages and opamps 8586, 167169, 591593

surface-mount (SM) resistors 5456, 7072, 132, 682

sweep middles tone controls 425

switchable peak/shelving LF/HF EQ 439

switched attenuator: resistors 362371; volume controls 362370

switched balance controls 388390

switched-frequency LF EQ 415

switched-HF-frequency Baxandall controls 410411

switched-gain balanced inputs 506

switched-Q variable-frequency Wien middle EQ 438

symmetrical clipping 662

switched-gain amplifiers 211214; MM/MC RIAA 248; MM RIAA 246247

Szilaki configuration 96

talkback: microphone amplifiers 660; split-format modules 461

tan-δ δ (tan-delta in capacitors) 73

tape replay: basics of tape recording 292293; Dolby HX-Pro 307; history of tape recording 292; load synthesis 305; multi-track recording 294; noise reduction systems 305306; the return of tape 291; tape heads 294295; tape replay 296304

tapped volume controls 334336

temperature coefficient 44, 53, 55

thermal distortion 136

thermodynamics laws 19

Thevenin-Norton transformation 19

thick-film resistors 5455, 6872, 499

thin-film 5355, 65, 68, 7273

third-order filters 181, 183, 186, 268275, 321, 739

three-band Baxandall EQ 428429

three-layer PCB 51

three-layer summing 611, 642643, 643

through-hole (TH) resistors 54, 56, 7071, 634

TID 194; see also slew limiting

time-constants 7475, 230231, 250251, 695696

TL052 opamp 133, 158160

TL072 opamp 127131, 129130, 133, 135136, 141145, 156162; guitar preamplifiers 317318; headphone amplifiers 565566, 566; line inputs 495496, 498; line outputs 538539; moving-magnet inputs 258, 261, 265266, 266; power supplies 719720, 720; signal switching 586, 607608; tape replay 303305, 303, 305

TL783C high-voltage regulator 731, 731

tolerances of resistors see under resistors

tone-balance controls 422423

tone controls 395; Ambler concept 423; graphic equalisers 443448; parametric middle EQs 440442; passive 396; preamplifier architectures 197198; return-to-flat (RTF) 416, 418; single-gang sweep middle 435437; sweep middles 425, 433, 435; switchable peak/shelving LF/HF EQ 439; switched-frequency LF EQ 415; tilt 422423; tone-balance 422423; variable frequency LF/HF EQs 412414, 416421; Wien fixed middle EQ 430; see also Baxandall tone controls; middle controls

tone-cancel switch 412, 416

total harmonic distortion (THD) 70, 70, 7281, 72, 7879; discrete transistor circuitry 102, 110114, 110, 112, 114, 116, 123; headphone amplifiers 563564, 566; level control and special circuits 689690; opamps for low voltages 169177, 173178; opamps and their properties 134, 144146, 145, 149, 149, 152156, 152155; signal switching 582584, 591592, 591, 601, 603; volume controls 351352

track current capacity 48

track resistance in printed-circuit boards 4749

track-return/group switch 452455, 457458, 462, 464

track-to-track crosstalk 4940

transformer balanced line inputs 490, 523

transformer balanced line outputs 553

transformer microphone inputs 466467

transformers, moving-coil 281282

transformer-tap volume controls 371

transimpedance amplifiers 24

transistor equation 87

transmission gates 580

Twin-T notch filter 189190, 190

two-layer summing 640643

two-ounce copper 47

two-transistor hybrid summing amplifier 647648, 647648

two-transistor series-feedback gain stages 117

two-transistor shunt-feedback gain stages 105108; bootstrapping 112114; improving linearity 109111; noise 112; as summing amplifiers 115116

ultra-low-noise: amplifiers 3839; balanced line inputs 530534; multipath amplifiers 3639; voltage buffers 37

ultrasonic filters 273

unbalanced line inputs 482484, 535

uncorrelated noise 2122, 21, 283

unipolar peak detector 671

unity 199204

unity gain 520

unity-gain buffer stages 88; CFP emitter-followers 9697; constant-current emitter-follower 92; emitter-follower stability 95; improved unity-gain buffers 98102; push-pull emitter-follower 9394; simple emitter-follower 8891

vacuum fluorescent displays 683

variable-frequency LF/HF EQs 412414, 416421

variable-frequency middle EQ 433434

variable-gain balanced inputs 507508

variable gain stages 199214; and active filters 205; dual-gain pot 203204, 209210; single-gain pot 199202, 206208; switched-gain amplifiers 211214

variable-voltage regulators 724

varigroove technology 215216

VCAs see voltage controlled amplifiers (VCAs)

very large power supplies 729

vinyl 215216, 297, 449; maximum signal levels from 219222, 220; problems 218

violet noise 17

virtual contact (signal switching): mechanical 577578

virtual-earth PFL detection 656657

virtual-earth summing 635636

Vogel, Burkhard 216, 288289

voltage coefficient 5355, 53, 7071, 70, 71, 73

voltage controlled amplifiers (VCAs): gain-control elements 689691; subtractive control 697

voltage doubler 731732, 732

voltage-followers 175, 526, 537, 564, 578

voltage noise 20, 2331, 128129; guitar preamplifiers 316317; line inputs 530531; moving-magnet inputs 255256; tape replay 303304; volume controls 352355

volume controls 325; active 339343; attenuator volume controls 362370; Baxandall active 344355; belt-ganged 359; DC 359; dual-action 331333; integrated circuit 372; laws 325327, 344; loaded linear pots 328330; loudness controls 373376; motorised 360; Newcomb and Young loudness control 377380; overlap penalty 356358; potentiometers 359; relay-switched 371; slide faders 337338; stepped 361; switched attenuator 362370; tapped 334336; transformer-tap 371

VU meters 676677

Walker, HP 229

“wall-art” power supplies 726

warp signals 180, 216217

wet monitoring 464

white cathode-follower 9394

White, Eric 94

white noise 1617, 714717, 715716

Whitlock bootstrap 522523, 522

Widlar, Bob 127

width controls (balance) 392394

Wien bridge configuration 663

Wien fixed middle EQ 430432

Willmann Tables 62, 241243

wirewound resistors 54

wiring 313

wiring resistance and cables 4647

WM8726 stereo DAC 740

WM8740 stereo audio DAC 738

WM8782 stereo ADC 735736

X2 capacitors 80

XLR connectors 466, 486, 488489, 525, 535536, 572

zero 206210

zero-impedance outputs 536542, 545

Zobel networks 282, 282, 523524, 523524, 553, 555, 562