Unbalanced Output To Balanced Input Cable

The structure of a balanced audio cable is similar to an unbalanced cable with one addition.

Unbalanced output to balanced input cable.

At the balanced input do not connect the screen wire to anything. Having cables with this kind of output makes it easy to directly connect unbalanced sources such as guitar effects directly into recording gear daws and signal processors with balanced inputs. Not only that it s possible that connecting a balanced output to an unbalanced input might be detrimental to the signal depending on the design of the balanced output stage. You can with some caveats.

A high quality isolator using an input transformer with an internal faraday shield increases rejection to almost 100 db at 60 hz and about 65 db at 3 khz. These are most commonly used with electric guitars which often output to an amplifier. At the unbalanced output connect the screen wire to the input ground pin together with the cold wire. In many cases you can reverse the process when feeding a balanced output signal to an unbalanced input.

Quarter inch ts tip sleeve cables are generally used for unbalanced signals. Unbalanced line level connections are usually implemented with rca jacks for audio while balanced line level connections typically utilize dual 3 pin xlr jacks for both the input and output. It can also be used to feed a balanced cable and input via a trs plug. The unbalanced gear will get it s ground via the mains so you want to separate the ground loop.

This produces an unbalanced output that can be used to feed an unbalanced input via either a ts or trs plug. The advantage of using balanced cables to connect between balanced outputs and balanced inputs is that balanced connections have better noise rejection thanks to a second inverted signal that has equal resistance to ground as the initial signal this inverted or reverse polarity signal is used to cancel noise and to make the signal more robust. The diagram above shows how the cable works. I ve read online that the best way to convert balanced xlr to unbalanced 1 4 mono is to buy a cheap passive di box and run it backwards xlr as input 1 4 ts as output.

For the best possible noise rejection use a 3 conductor cable wired as in figure 2 from the unbalanced output to the isolator input. Connecting mains powered unbalanced outputs to balanced inputs. In both cases one jack is normally used for each audio channel left and right. In most cases the negative output of a balanced output can be connected to ground but in some cases it should be left disconnected.

The impedance balancing means that the balanced interference rejection on that circuit is retained.