View Single Post
Old 21st Nov 2019, 2:46 pm   #5
terrykc
Rest in Peace
 
Join Date: Nov 2010
Location: North Hykeham, Lincolnshire, UK.
Posts: 515
Default Re: Building a 5 valve A.C. amplifier from scratch

You say you have various parts available but we don't know what they are!

That is an American design which is intended as a Public Address, rather than Hi-Fi amplifier - hence the simple tone control. I assume that any valves you have are more likely to be European, rather than US types although, of course, most types have equivalents in the other range.

However, assuming the parts you have are suitable, I wonder if you would be better off building a true High Fidelity amplifier such as the Mullard 5 - 10? (Mullard being the UK subsidiary of Philips.)

I built several of these excellent amplifiers in the past and they perform very well indeed.

There is a full reprint of the original design as published here:

http://www.r-type.org/articles/art-003e.htm

I think you'll also find the circuit is drawn in a much clearer way which should make it much easier to follow.

There is a full description and a number of options for you to chose from. The version with controls offers treble and bass boost and cut adjustments - much more comprehensive that the US design.

Full constructional details are given and the tag board mounting makes for a very simple and clean layout.

Take careful note of the earth bus bar. Whatever you decide to build, you should use the same earthing arrangement. If you don't, you will live to regret it - probably as soon as you switch it on for the first time!
terrykc is offline