The Valve Wizard

Engineering mojo since 2005. Last updated: 7 June 2014

YOU'VE SEEN THE WEBSITE, NOW READ THE BOOKS!
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Click the images to find out about the books.
























News:

7 June 2014: can now buy a professional PCB for my U-Boat suboctave pedal project! The PCB is avalable from TH Custom Effects in Germany.


15 November 2013: I've been getting a lot of mail about my power supplies book. I'm sorry to say it has been removed from print because I don't like it. It contains too many mistakes and typos, and it doesn't match the style of my preamps book. Now, before you ask, I do intend to update it eventually. It may take a couple of years, however, as I am currently working on a different title. And before you ask your next question, no, it isn't about power amps. I won't be writing about those for even more years! I'm sure this is a big disappointment to many readers, but that's just the way it is. One man can only do so much! The power supply book is therefore unavailable until further notice.

On an unrelated matter, I now have some more universal output transformers for sale (UK only).

Interested in making your own ribbon microphones?
Visit: DIY Audio Components!

Introduction
Welcome to the wonderful world of valve amps! If you're here then you're probably thinking about tinkering about inside one. Building your own guitar amp is a rewarding pastime, but learning how to do it can be time consuming and frustrating sometimes. It is relatively easy to find introductory information on how to design simple amplifier stages, and it is also fairly easy to find extremely advanced information on complex circuit design, and nearly all of it is intended only for hifi! This website aims to fill the gap between the two extremes. I have also tried to remove unnecessary maths and leave only the essential formulae and rules of thumb. This should make the design process quicker and less confusing, leaving more time for the actual building. However, this site assumes that you know some basic principles already, like Ohm's law, roughly how a valve works, etc. If you don't know these things yet then I recommend you read some introductory electronics material. Even so, I have done my best to write these tutorials cook-book style so that even a layman can follow the instructions and design a working circuit without actually knowing how it works- but it certainly helps to understand first. Although aimed specifically at designing guitar amplifiers, principles of hifi have been included here so that audiophiles may find something of use too, and guitarists should be able to learn some of the science behind the mojo.

Disclaimer:
Building and modifying amplifiers is DANGEROUS (like most fun things). Valve amplifiers invariably contain both very high voltages and high currents, capable of killing you. Whilst anyone can learn the skills to build an amazing amplifier, it goes without saying that you must never work on a live amplifier! I provide the information on this site free of charge, and it is up to you to exercise caution and common sense at all times to avoid electrocuting yourself, and make your amplifiers safe to use. I am not responsible for your negligence. Building valve amplifiers is also more addictive than nicotine; you have been warned.

This site is always under construction.

Contact: Be sure to put 'valve' or 'tube' in the subject title or your message may be blocked!
Suggestions, comments, criticisms welcome.