Greetings my good DIYers!
I am resurrecting a project using a Sure AA-AB32186, an older design using TK2050 and similar to their WONDOM amp. It will be in a cast aluminum case intended for high power electricity controls. I'm using an isolated line-in so it could be treated as balanced if I get the grounding right. My layout puts goodly distance between P/S, speaker outs, and line-in signal wiring.
If there is a generic link for nub questions on these topics, please point me there. Otherwise::
1) Do I need to worry about shielding line-in signals inside an aluminum enclosure? (I will certainly be using twisted pair.)
2) Where should my single point ground be oriented? The amp board? The P/S connector? Other?
3) Is it possible to have all signals on a single point ground referenced to the amp board, and other stuff, like LED grounds, on a generic undisciplined ground?
4) Any other advice on these topics?
I can post pics of my layout when all the parts have arrived, if that would be helpful.
I am resurrecting a project using a Sure AA-AB32186, an older design using TK2050 and similar to their WONDOM amp. It will be in a cast aluminum case intended for high power electricity controls. I'm using an isolated line-in so it could be treated as balanced if I get the grounding right. My layout puts goodly distance between P/S, speaker outs, and line-in signal wiring.
If there is a generic link for nub questions on these topics, please point me there. Otherwise::
1) Do I need to worry about shielding line-in signals inside an aluminum enclosure? (I will certainly be using twisted pair.)
2) Where should my single point ground be oriented? The amp board? The P/S connector? Other?
3) Is it possible to have all signals on a single point ground referenced to the amp board, and other stuff, like LED grounds, on a generic undisciplined ground?
4) Any other advice on these topics?
I can post pics of my layout when all the parts have arrived, if that would be helpful.
I'm gonna sort of answer my own question with this link. It mainly refers to mixed signal boards combining digital and audio frequencies. It does make references to normal audio and the special case of ADC/DAC where the digital and audio are intrinsically/physically overlapping.
It seems to me the way to go for my design is a star ground oriented to the filter cap array.
The power source is an external DC supply, so no AC enters the enclosure. I can make 18AWG Vcc and ground rails as part of the filter cap array, which will be <1" physically from the amp board power connectors. Then, all grounds, including the amp board, speaker outs, line level input signal/shield, indicator LEDs, will tie there. All signal, Vcc and ground wiring will follow physically divergent paths with no overlap.
It seems to me the way to go for my design is a star ground oriented to the filter cap array.
The power source is an external DC supply, so no AC enters the enclosure. I can make 18AWG Vcc and ground rails as part of the filter cap array, which will be <1" physically from the amp board power connectors. Then, all grounds, including the amp board, speaker outs, line level input signal/shield, indicator LEDs, will tie there. All signal, Vcc and ground wiring will follow physically divergent paths with no overlap.