Hello,
I have successfully build an audio pre-amplifier based on Self Douglas préAMP 2012 (2), to the exception that I removed all the TONE controls section, the MC section, the Subsonic Filter section, the IEC amendment section, as well as the variable gain section from jumpers.
Now I want to make a new guess including the MC section, the Subsonic Filter section, the IEC amendment section and the gain section. My question is regarding the ground plane. Below I share a capture of the solder side where the audio ground traces are highlighted. TP1 is my HQG (High Quality Ground) where the analog ground join the Power Supply. R717, 718, 817 and 818 are connected from the components side!
I tried to create a ground plane on the components side, excluding the digital ground traces that goes to the relay and it's transistor. You'll find below another capture, again with the ground traces and ground plane highlighted. Notice that the ground plane join the Power Supply ground at the HQG. Also of course, the R* above have their traces irrelevant with the ground plane!
We can observe that the digital ground traces are excluded from the ground plane to assure that the digital ground goes directly to the big cans of the power supply. All the donuts that are highlighted on the ground plane of the picture above are actually making a second connection to the analog ground via thermal brake (cross) like these ones here:
So my question(s) is regarding the possible ground loops that this ground plane can create.
I admit that this kind of situation has always intrigue me...
Thanks, in advance...
I have successfully build an audio pre-amplifier based on Self Douglas préAMP 2012 (2), to the exception that I removed all the TONE controls section, the MC section, the Subsonic Filter section, the IEC amendment section, as well as the variable gain section from jumpers.
Now I want to make a new guess including the MC section, the Subsonic Filter section, the IEC amendment section and the gain section. My question is regarding the ground plane. Below I share a capture of the solder side where the audio ground traces are highlighted. TP1 is my HQG (High Quality Ground) where the analog ground join the Power Supply. R717, 718, 817 and 818 are connected from the components side!
I tried to create a ground plane on the components side, excluding the digital ground traces that goes to the relay and it's transistor. You'll find below another capture, again with the ground traces and ground plane highlighted. Notice that the ground plane join the Power Supply ground at the HQG. Also of course, the R* above have their traces irrelevant with the ground plane!
We can observe that the digital ground traces are excluded from the ground plane to assure that the digital ground goes directly to the big cans of the power supply. All the donuts that are highlighted on the ground plane of the picture above are actually making a second connection to the analog ground via thermal brake (cross) like these ones here:
So my question(s) is regarding the possible ground loops that this ground plane can create.
- Should I forget the components ground plane and stick with the original analog ground solder traces?
- Or delete all the analog ground solder traces and keep the components ground plane?
- Or keep both of them without worrying?
- Or either exclude all the analog ground donuts (cross) from the ground plane to assure that the ground plane doesn't create a second electrical ground connection, i.e. a loop?
I admit that this kind of situation has always intrigue me...
Thanks, in advance...