(This posting amended and added on 24/10/2008)
Paul

Here’s the headphone amp (picture link gone) circuit. It’s from this old ETI mag thing I’ve got. The headphone amp was used in the Crawling Chaos studios as it could drive 5 pairs of headphones connected in mono simultaneously!!!)

Also, I’ve got a little Class A amp circuit from the same source. I’ll attach that later as well! It’s not particularly good as the 741 would need changing as well as using some less noisy transistors. But it WILL sound acoustically warm and analogue… 🙄 The text has a reasonable walk through of the circuit operation with a bit of the design criteria behind it so it should give you a few more pointers for your understanding. As soon as I can be the bloomin’ scanner to work!
I’ve added a few books that might build on the knowledge for this post – SP
The amp looks like an interesting weekend project. You say it has a warm sound? Interesting…