影音快報: Accuphase A-70純甲類立體聲後級

auraheart

graffiti 發表於 2014-3-28 10:56
44.3 kg is not heavy, just right weight for a 60 watts Class A amp.
I consider it very heavy alrea ...

Many ways of building an amp.  Class D 200 watts could weight less than 20 lbs..  This is a true Class A amp where its efficiency is about 20% and rest of 80% becomes heat.  Claimed Class A never weight that much.  (Threshold 400A was the first well known claimed Class A amp in the 70s, 25kg/100 watts)  You see this is a high current Class A amp using 12 power out-put transistor per channel.  (Typical 200-300 Class AB amps use 8 power transistors)  Not often you see the transformer has heat-sink build-in as this amp.  In sum, current, heat, Class are key factors that contributed to weight. Not sure about the voltage, lack of technical data.
Btw, a true Class A is "on" at all time.  Even on standby, its power consumption is very high.  Many "dynamic" or pseudo–class-A designs has much less stand-by requirements.  Can check out link below, has a brief description on Class A amp.
http://www.stereophile.com/solidpoweramps/694krell

補充內容 (2014-3-28 14:30):
Weight thing is subjective too..  I like heavy equipment, and that is me. Others maynot feel the same.  Japanese gear is not known to be heavy either.  Must be reasons why this unit weights so much, objectively.

141Boss

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