Vacuum Tube Amplifier Basics

There is a growing number of audio enthusiasts and hobbyist interested in creating their own vacuum tube amplifiers. If one has the necessary technical information, high quality tube amplifiers can be assembled. Although it is true that accurately calculating electronic circuits can involve complicated formulas, for the electronic hobbyist it is not necessary to perform at the level of an electrical engineer. With some basic knowledge, it is possible for the hobbyist to design and build vacuum tube audio amplifiers that perform well. For the novice not versed in electronics, several sections of the book cover electronic basics that pertain to vacuum tube circuits. Includes Ohms law, voltage, current, power and watts. Explains capacitors, series circuits, parallel circuits, voltage dividers, reading circuit drawings plus other related information. Principles of vacuum tube operation voltage amplifiers and power output are explained. Includes function of grids, effect of tube capacitance, tube resistance, heat dissipation, bias, miller effect and calculating voltage gain. A table of component values for the popular 12AX7 in various operating parameters simplifies pre-amplifier stage design. Power supply sections cover vacuum tube and solid state rectifier conversion of AC to DC and DC filtering. Amplifier design example takes you through the steps of designing a single ended ten watt amplifier with volume and tone controls. Working with electronics and vacuum tube circuits requires some math. Circuit calculations in this book use various forms of addition, subtraction, multiplication and division. Formulas are all solvable using a standard 12 digit calculator (requires a square root key). Calculations are presented with examples. Project layout circuits include a line amplifier with 25db gain, triode balanced-unbalanced input stage, tone control stage, turntable pre-amplifier, 6V6SE Class A stereo amplifier, 6V6SE Class A monoblock amplifier, 30 watt monoblock amplifier and a basic 5 watt guitar amplifier. The 30 watt monoblock amplifier is designed for tube rolling using various type output tubes.