Why no smps used for audio power amplifiers?

Question

Generally transformers are the power source

Answer 1

Switch-mode power supply and Class D amplification technology is moderately common these days in the consumer electronics (especially in car audio) and pro sound markets. Consumer electronics companies such Audio Research, Ayre Acoustics, Ballmann/behold, Bel Canto, Channel Islands, Chord, Halcro, Linn Products, Naim, Pioneer, Rotel, Jeff Rowland Design Group, Sony, Spectron, Tact Audio, and Yamaha, to name a few, produce (or have produced) switch-mode audio amplification products.



The following represents a very small sample of consumer electronics products that utilize switch-mode power supply technology:



Flying Mole

http://www.flyingmole.co.jp/new_en/index...



Halcro / Halcro Logic

http://www.halcro.com



Pioneer SC-09TX Elite A/V Receiver

http://www.pioneerelectronics.com/PUSA/P...



Jeff Rowland Design Group

Switch-Mode Power Supply Technology

http://www.jeffrowland.com/Technology/Sw...



Spectron Digital Audio Amplifiers

http://www.spectronav.com



################ ADDITIONAL RESOURCES ################



The Truth About Digital (Class D) Amps

http://www.bryston.ca/newsletters/74_fil...



Class ‘D’ Amplification

http://www.avreview.co.uk/news/printable...



Hypex Electronics B.V.

http://www.hypex.nl



ICEpower

Academic Publications

http://www.icepower.bang-olufsen.com/en/...



(Additional information and resources on the topic of switched-mode power supply" technology can be found on Wikipedia.)

________________________



Bruno Putzeys: The Sound Of Music (Extended Play)

http://www.spectrum.ieee.org/print/5953

 

Answer 2

Yeah, don't some high end stereos use them? If not, it's probably because they run off just one rail voltage and step up or down elsewhere in the circuit. Linear's really fine for a stereo or TV, I guess, just not a computer. There's even tricks to avoid the transformer, like stringing everything like a chrstmas tree light set. While mostly associated with tube sets and tube TVs, SS TVs and radios ran hot floating chassis into the 80's.