#### Book Description

Our new book applies 21st-Century technology to the design of guitar amplifier preamps, power amps, and power supplies. Computer-based visualization replaces the traditional litany of mathematical formulas. The book's graphing calculators, free on this website, are designed for smartphones and laptops, making them as portable as the book that uses them.

The book explains the principles of vacuum tube electronics and the design of preamp voltage amplification stages, cathode followers, tone stacks, power amps, phase inverters, negative feedback, and power supplies. An entire chapter is devoted to sculpting the dynamics of overdrive and harmonic distortion.

#### Author

Richard Kuehnel is a member of the Circuits and Systems Society of the Institute of Electrical and Electronic Engineers.

#### Introduction

**Warning: High Voltage!...1**

##### Less Math, More Understanding...1

##### Tube Amp Calculators...3

##### Acknowledgements...5

#### Chapter 1: Electronics Fundamentals

##### Electric Charge and Electric Current...6

##### Work, Voltage, and Power...7

##### AC and DC Voltages in a Guitar Amp...8

##### Ohm's Law, Resistors, and Resistance...9

##### Voltage Dividers...11

###### Potentiometer Taper...12

###### Inter-Stage Attenuation in a Preamp...14

##### Capacitors and Capacitance...15

##### Decibels and Bode Magnitude Plots...20

##### Inductors and Inductance...23

##### Ideal Transformers...26

##### Real-World Transformers...28

#### Chapter 2: Vacuum Tubes

##### The Edison Effect...32

##### Diodes...33

##### Triodes...36

###### Plate Characteristics...37

###### Transfer Characteristics...38

###### Plate Resistance, Amplification Factor, and Transconductance...39

###### Grid Current...42

##### Multi-Grid Tubes...42

###### Plate and Screen Current...44

###### Plate Characteristics...46

###### Transfer Characteristics...48

###### Drawing Plate Characteristics for Power Amp Design...49

#### Chapter 3: Preamps

##### Voltage Amplification...52

##### DC Operating Point...54

##### Cathode Bypass Capacitors...60

##### AC Load Line...64

##### Coupling Capacitors...65

##### Grid-Stopper Resistors...68

##### Bright Bypass Capacitors...71

##### Plate Bypass Capacitors...75

#### Chapter 4: Cathode Followers

##### Trading Gain for Lower Output Impedance...76

##### DC Coupling...81

#### Chapter 5: Tone Stacks

##### The Bassman 5F6-A and JMP50 Model 1987 Stack...84

###### How It Works...84

###### Modifications...88

###### Potentiometer Taper...88

###### Driving the Stack Directly from a Voltage Amplifier...89

##### The James Stack...91

###### Orange OR120 (Graphic Mk II)...91

###### Fender Twin 5D8...94

##### Tone Shaping - The Big Picture...96

#### Chapter 6: Power Amps

##### A Transformer in the Plate Circuit...98

##### Single-Ended Design...101

###### Learning from a 6L6GC Data Sheet...102

###### A 6L6 Single-Ended Design...105

##### Parallel Design...109

##### Push-Pull Design...110

###### Basic Concepts...110

###### A 6V6 Push-Pull Fixed-Bias Design...113

###### Converting to Cathode Bias...115

###### Power Supply Voltage Sag...116

###### Wrapping Up the Designs...118

##### Grid-Leak Resistors...120

#### Chapter 7: Phase Inverters

##### Paraphase...122

##### Concertina/Cathodyne/Split-Load...126

##### Long-Tailed Pair - How It Works...130

##### Long-Tailed Pair - A Design Procedure...133

#### Chapter 8: Negative Feedback

##### Generalized Concept for Guitar Amplifiers...140

##### Single-Ended Design...141

##### Long-Tailed-Pair Design...143

##### Final Comments on Negative Feedback...146

#### Chapter 9: Power Supplies

##### Transformer Considerations...148

##### Rectifiers and DC Voltage Sag...150

##### Ripple Filtering and Decoupling...154

##### Negative Bias Supplies...155

#### Chapter 10: Overdrive and Harmonic Distortion

##### Grid Current Effects...158

##### Bias Excursion...160

##### Harmonic Distortion...163

##### Mesa/Boogie Mark I Overdrive Harmonics...167

##### Push-Pull and Negative Feedback Effects...170

#### Some Final Words on Guitar Amplifier Design...172

#### Index...174