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Old 24th May 2020, 4:22 pm   #49
Craig Sawyers
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Join Date: Nov 2010
Location: Oxford, UK.
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Default Re: How much DC on your mains ?

Quote:
Originally Posted by PJL View Post
Do top end hi-fi amps still use mains transformers?
A mixture. Class D can use either a switcher (either integrated with the amp, or separate) or conventional mains transformer.

Likewise class B or AB - a mixture of both.

One of the most expensive (mono) units, long obsolete - the Halcro - used two switchers one after the other. The mains facing one was power factor corrected, and the second one derived the rails that were used by the "conventional" amp. That was a FET output with both feedback and feedforward to give sub-ppm distortion.

https://www.stereophile.com/content/...plifier-page-2

Everything in the bottom half is power supply.

Craig
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