In article , Don Pearce
wrote:

I'm just thinking of the cost of that huge mains transformer - and the
heat sinks.

Tell me about it! :-/ I had to make a +200W pc amp to meet the old IHF707
specs. Then have reviewers whine that the result was expensive. of course
it was when you added up all the heavy metel required for 1/3rd power
running for an hour before testing. Oh, and the external heatsinks weren't
allowed to exceed 60 C.

Then factor in that I was determined to have the amp happily drive loads
down to below 2 Ohms, etc. And have a transformer that didn't 'leak' too
much field and spoil the quality.

No doubt Rotel faced similar 'expectations' from reviewers and buyers. When
in reality an end user would almost never push such an amp anywhere near
its limits. If they did, their speakers and ears would probably have been
the main limit. 8-]

I have wondered since about modifying the design to run as a lower output
Class-A. In some ways it would have been simpler.

Jim

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