Goals:
- Uses TDA7293 integrated amp IC
- Single board per chip/channel as small as reasonable with 2 layers without compromising noise performance
- Simple interface to power and IO signals
- Combine three together sharing a toroidal and main power filter caps for stereo bookshelfs + optional sub
- Use reference schematics and layout as guides in order to minimise time to completion and effort required
- Linkwitz Riley 24db/octave two way + merge electronic crossover to handle splitting signal for sub and bookshelfs
- Internal star grounding scheme
- Add some sophistication and quality by force to the circuit
- Incorporate ground lift circuit to ensure ground-loop free operation
- Utilise clip detection feature to drive LED on front panel per channel (20mA, make it obvious)
- 3x TDA7293V
- 3x PCBs (yet to be designed)
- 3x other required components on board
- 1-3x solid heatsink(s) with lowest thermal resistance possible for space
- 2Nx big filter caps (2 or 4 or 6 or 8, whatever makes sense costwise/physically
- 1x large bridge rectifier
- 1x 250VA 30V toroidal transformer
- 1x Reused mains X cap (to kill line noise)
- 1x Reused old 70s/80s cassette deck housing including RCA jacks