battery powered power amps

[hahfran]

Some yaers back an extremely expensive battery powered power amp gained tons of superb reviews. Of course !
Thinking about a way to combine battery powering with inexpensive switching PSU.
Accu packs for DIY home improvement tools such as drilling machines are relatively cheap they come with for ex. 10.2 Volts capacity 1.5 Ah.
So how to combine battery powered preamp with switching PSu powered power amp?
The obvious difficulty is the VAS. A first idea is attached here intended for
Thermal Track power BJTs. It should be noted the output configuration is just a current mirror.

 

[iaxxaxxai]

Interesting idea. Any chance the Dynaudio amplifier from the 90's is the inspiration? 😉

 

[hahfran]

No its an idea once published by Philips Netherlands lab. Around 1978 or so.
Thermal instability was a major issue.