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Old June 9th 04, 03:18 AM posted to uk.rec.audio
Trevor Wilson
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Posts: 242
Default Anyone Got a Cheap Valve Power Amp or Integrated Amp For Sale?


"Wally" wrote in message
...
Trevor Wilson wrote:

* People who buy audio equipment, without first evaluating the
product/s deserve all the problems they are likely to encounter.


Why?


**I'd have thought that the answer was obvious.


Why should someone who elects to take a different approach from what you
advocate *deserve* problems?


**They only deserve problems, AFTER ignoring good, logical, sensible advice
(like listening/examining first). Kinda like those guys who buy the 'white
van' speakers, even after having been warned about them. Still, the 'white
van' speaker buyers, usually think they're buying stolen goods, so maybe
they do deserve what they get. :-)



**A good audio transformer is constructed using 'interleaving'. That
is: A portion of primary is overlaid with a portion of secondary,
then more primary, then more secondary and so on. Interleaves upwards
of 13 are not uncommon in high grade audio transformers. Such a
process is extremely time consuming and difficult to get right. Power
transformers (which many low end valve amp manufacturers use as
output transformers) are much cheaper to produce. One winding is
typically bunged on top of the other. End of story. They also perform
poorly.

Good audio transformers also use high grade, 'grain oriented' silicon
steel. This costs more money than the non grain-oriented stuff.


Thanks.


**My pleasure. I learned about such things many years ago. I serviced an
amplifier whose output transformer had gone belly-up. I took it to the
rewinder. He called me a few days later, uttering many profanities. It had
15 interleaves and cost a small fortune to rebuild.


--
Trevor Wilson
www.rageaudio.com.au