Newie Saying Hello ;)

Hello Everyone🖐️ ... this is HappyDoer here ... a complete Newbie to this amazing community!!! ☺️
I'm a DIY hobbyist hoping to gain some amazing insights and inspirations from many of the seniors here! 😚

My interest includes ...
(1) Zero feedback I/V output R2R DAC design
(2) DHT preamp tubes design
(3) Class A and Class D amp design
(4) DSP active X-Over design
(5) OB and TL speaker design