Grounding for multiple transformers

[jetbat]

Hi. I want to have two transformers powering two groups of circuits in one amplifier. One transformer will be 36VCT and the other will be 300V (no center tap). The audio signal will be passing back and forth between the two groups. Do I want to have the grounds remain separate or should they be tied together.

Thanks
Scott

 

[jetbat]

Here is what I was thinking. The audio signal passes between the circuits on a single wire. It needs a ground connecting the circuits too. So I attached a schematic of how I think they might be connected. The red resistors are added and the red grounds are connected. Does anyone see a problem with this?

Scott

 

[sinuhe97]

Do not attach the red resistors and ground in that area. It could cause problems. Instead, ground the center tap of that 36V PS along with the negative connection of that 300V PS. You should be fine with this configuration.

 

[Bakmeel]

For minimal ground loops, attach the ground of the 300V circuit physically close to the negative terminal of the capacitor bank.
Then attach the CT circuit to ground physically close to the Center (0V) connection of that capacitor bank.
If possible, minimize the distance between the two capacitor banks, or at least try to keep impedance as low as possible (use bigger wires)

 

[jetbat]

I originally thought to connect the CT to the negative of the 300V, but I was not sure if it would work. I will connect them that way. The two filter banks are going to be on the same board so I can make the connection short and I'll use a thick wire.

Thanks
Scott