class A enclosure design PK V3

Patrick K. (aka EUVL) wrote an interesting article for Vol 3, "Design Considerations for a Class A Amplifier Enclosure". This is an subject that is very rarely treated at all. The article gives a complete treatment of all involved issues and can be used as a procedure to calculate the required heatsink capacity for a project, as well as selecting a suitable product to mee those requirements. Therefor, Patrick and I have agreed to place it online for further dissemination.