Trevor Wilson wrote:

So, it's basically the same method as the two-layer version,
repeated. Does the lay-up of the winding have to be done in some
kind of even pattern, or can it just be wound on to produce layers
of even thickness? You said that the process is difficult to get
right - what bits would be difficult to get right?

**The process is not so much difficult, as time consuming and hence,
expensive.

Does that mean that the specifics of the lay-up aren't too critical?


With valve amplifier output transformers, there is no such
thing as a 'free lunch'. You want a quality amp, you MUST spend the
Quid on decent output transformers.

Are there substantial savings to be made by winding them oneself? Any major
pitfalls?


**Low losses, high permeability, which provide better performance than
regular steel. I don't know about the cost. I would speculate that
around 300% higher than the regular stuff.

Righto.


--
Wally
www.artbywally.com
www.wally.myby.co.uk