That is neat Raj.RSK said:This I have constructed and works very well.
No need for additional transformer.
R1 & R2 can be configured for various voltage from +25V to +70V
Includes AC detect for delay turn on and off for speaker.
RSK said:The circuit is by Siliconchip magazine issue July 2007 under 20W class A amp.
Please get it as I cannot post it here.
Carlos, I will send you the image of construction. Please post it here as I do not know how to load here. The image is too big.
Working very well. Tested with 1.5V dc input and it works good.