In article , Sala Massimo
wrote:
Still many thanks for your help.

About the A1, what can I say?

When I purchased the A1 I was 19 years old, and it seems to me to buy a
"Cadillac" (also for the efforts to save the money!). It was really a
pleasure to listen to it, with Celestion 5 speakers.

Time goes by... I come to the feeling the A1 is a myth: * I thought it
is 20 Watt class A, now I read it is only 2 Watt class A... It heats
like a true class A to tweak the listeners ?

To be fair, chances are, most users will be using only a couple of watts
most of the time, so in practical terms I'd guess it is 'more A than B'.
:-)

* The volume pot failure is a design failure.

Oversight, or perhaps a calculated risk. TBH variable pots all tend to wear
out in use, so it is perhaps hard to feel 20-odd years is not enough. It is
possible to design and choose components with a view to a longer life, but
some luck comes into this, and from the designer's POV they may feel that
by then they'll have a better design which they'd prefer you to buy! ;-

Above said, I would not personally have arranged the design as they did.
However their approach does have some advantages, so this is swings and
roundabouts.

* Some components (example the caps) are not well suited for the high
temperature inside.

This again is a trade-off problem. If you want high bias (class A) and a
small box, you end up with high temperatures. As you say, some components
do not really like this... However dealing with it puts up the
price/size/etc...

* Users report different failures.

* Musical Fidelity feedback is null...

That bit is unfortunate if representitive.


Better for your wallet, more amusing and satisfying is do some DIY
project!

I'd agree with that! :-)

Slainte,

Jim

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