Thanks.. Yah, all my grounding is going back to the main system ground, just in case I want to use a ground lift circuit at some point.
Thanks.. Although on Slide 37 I think it says to basically put the 10R resistor in a different place, i.e. not between the input on the PCB and the RCA socket, but further down, towards the main ground I believe. Am I reading that wrong?
It can be done that way also, and you can try both ways to see which is best in your amplifier.
The "amplifier power ground" is the ground terminal of the single-supply big power supply capacitor (not the chassis).
The "amplifier power ground" is the ground terminal of the single-supply big power supply capacitor (not the chassis).
The idea of the resistor in a ground wire is to make the current flow somewhere else, as it likes to takes the way of least resistance, so the "bad" noise stays away.
It can only be used in low current ground wires. The input of a power amp should only carry some voltage and very minimal current, so the 10-100 Ohms in the ground line do not really matter compared to the maybe 20-47kOhm of the hot input side. These are last resort tricks you may try if a usual ground concept does not work for your build.
Make a sketch of your grounding points and lines, sometimes that way you realize where a loop is formed.
Also keep an eye on induced hum, it may enter even a shielded wire at some position you do not except at all, not only near a transformer or mains wire.
A very little change in routing may make the difference.
This chip amp can be totally quiet, it is not to blame for any hum.
It can only be used in low current ground wires. The input of a power amp should only carry some voltage and very minimal current, so the 10-100 Ohms in the ground line do not really matter compared to the maybe 20-47kOhm of the hot input side. These are last resort tricks you may try if a usual ground concept does not work for your build.
Make a sketch of your grounding points and lines, sometimes that way you realize where a loop is formed.
Also keep an eye on induced hum, it may enter even a shielded wire at some position you do not except at all, not only near a transformer or mains wire.
A very little change in routing may make the difference.
This chip amp can be totally quiet, it is not to blame for any hum.