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Old November 26th 04, 04:14 PM posted to uk.rec.audio
Jim Lesurf
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Default Every amp in one

In article , JustMe
wrote:
"Jim Lesurf" wrote in message



Pics of the actual amps I'm using (including internals) are at the same
URL I gave previously, or via
http://www.alchemisthifi.info/ranges...aken_index.htm If by
"plastic pack" you mean they come in strips in plastic packaging, then
that rings true with what I've seen of op devices used in other
Alchemist amps. What significance would this hold?


Being able to identify the pack tells us the probably max power ratings of
the devices and the thermal conductivity between the active devices and the
heatsink. This then has implications for what current*voltage levels are
'safe' for normal operation. For simple class A, this then may indicate the
current and voltage chosen by the designer, and the implied maxium levels
available in class A. Thus can do some 'guesstimates' of these things
without actually looking up the device number. The complication is that the
safe power 'derates' with the temperature, so a good pack and heatsink
allow you to get higher powers from the same actual semiconductor device.

Given the comment you make elsewhere about the dual PSU *not* increasing
the power I am wondering if the peak current and voltage are being
deliberately limited for thermal and safety reasons. (Safe here means the
devices continue to work OK.)

Slainte,

Jim

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