Hi
I built a DI box (BAL to UNBAL) and its inverse (BAL to UNBAL) converter, all in one box. The unit is mains powered in an old PC power supply box.
I am killing ground loop between the steel chassis/mains earth, and the signal ground by using a 100ohm//100nF cap parallel combo.
I however I can't kill a ground loop between a signal going into say the BAL input and its UNBAL output.
Where is the best place to put a ground lift switch? On the input XLR or the output TS plug?
Inversely where to put it on the UNBAL input and BAL output converter?
My thinking says put it on the XLR sockets of both sections. Any thoughts????
I will be using a 100ohm//100nF bypassed by a switch as the ground lift circuit.
I built a DI box (BAL to UNBAL) and its inverse (BAL to UNBAL) converter, all in one box. The unit is mains powered in an old PC power supply box.
I am killing ground loop between the steel chassis/mains earth, and the signal ground by using a 100ohm//100nF cap parallel combo.
I however I can't kill a ground loop between a signal going into say the BAL input and its UNBAL output.
Where is the best place to put a ground lift switch? On the input XLR or the output TS plug?
Inversely where to put it on the UNBAL input and BAL output converter?
My thinking says put it on the XLR sockets of both sections. Any thoughts????
I will be using a 100ohm//100nF bypassed by a switch as the ground lift circuit.
are you sure that the noise is indeed a ground loop?
without a schematic and more details it hard to say if your proposed solution will work.
when you say:"I built a DI box (BAL to UNBAL) and its inverse (BAL to UNBAL)" shouldn't the inverse read (UNBAL to BAL) or do you mean it's the same but with inverted signal?
also without seeing your circuit the idea of using the "lift" on a TS ouput jack would result in an open circuit would it not?
without a schematic and more details it hard to say if your proposed solution will work.
when you say:"I built a DI box (BAL to UNBAL) and its inverse (BAL to UNBAL)" shouldn't the inverse read (UNBAL to BAL) or do you mean it's the same but with inverted signal?
also without seeing your circuit the idea of using the "lift" on a TS ouput jack would result in an open circuit would it not?
Sorry for the late reply. TURK you are correct- I meant Unbal to Bal. I have decided to add 100 ohm resistors bypassed with 100nF caps on all xlr pin 1's. I then added a switch across the res/ cap network. Works great!!!
Because my unit is powered by mains, I also added a ground lift switch between mains earth(chassis) and signal ground.
I had to do this because essentially three units can be grounded at the same time with this setup, and that can cause all sorts of crap.
Because my unit is powered by mains, I also added a ground lift switch between mains earth(chassis) and signal ground.
I had to do this because essentially three units can be grounded at the same time with this setup, and that can cause all sorts of crap.
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