This is
a DIY Signal Isolation/Unbalanced to Balanced Converter Box.
I'm using high-quality MADE IN USA Audio Output transformers
to create this SI/UnBalanced-to-Balanced (or Balanced-to-Unbalanced)
Converter Box. In addition, a Ground Lift switch is provided.
On this
picture, you can see the 4 TRS jacks (2 per channel x 2 = 4),
the 2 large audio output transformers, and the ground lift switch
in the middle.
And this is the picture of the finished project. The switch on top
is the GND LIFT switch.
The jacks from left to right, are Unbalanced in/out, Balanced in/out
(for Channel 1), Unbalanced in/out, Balanced in/out (for Channel
2).
The unit can perform as a Unbalanced to Balanced converter, or as
a Balanced to Unbalanced converter.