Book excerpt: Most musicians would like to understand how their amplifiers work. For reason to either get a better tone, explain that tone to their serviceman, prevent an amplifier from failing on stage, perform a quick-fix on the job, do their own maintenance, maybe even start their own repair or custom amp business. This book is intended to provide an actual Workbook that can be opened up on your workbench and used to study, service, or modify tube amps. The book is laid out in a "cadence" of schematic on top, with the appropriate layout underneath. This allows you to see both drawings at the same time. It also means that some pages are intentionally left blank, so as to not break the "cadence." These pages can be used for note taking. After all, this book is meant to be used. Contained in the chapters are reference pages for Jensen Speakers, Fender Transformers, and Accutronics Reverbs.