How to convert an unbalanced sound line to a balanced sound line

By | April 8, 2021


Connect the unbalanced cable to the impedance matching transformer, in the socket marked ‘high-z’ or ‘input.’ You can use an adapter adapter in the high z-end if the cable connector does not match the transformer connector.


Connect the balanced cable to the impedance of the transformer, the plug marked ‘low-z’ or ‘output’.


Connect the other end of the balanced cable to the input of the audio component.


Switch on all equipment and tests for operation.

Tips and warnings

  • It is physically possible to convert 2-wire components to 3-wire components using custom cables and ground cable terminals, but the impedance of the component does not change. Balanced components are low impedance (low z) and unbalanced components are high impedance (high z), and are not compatible in many cases. Use an impedance matching transformer to effectively change the impedance of the audio signal and to provide the correct connection type.
  • When using unbalanced connection adapters, make sure they are 2-wire adapters. In general, 3-core adapters are not compatible with unbalanced cables.
  • Some modern components make it possible to use both cables with high and low impedance cables and do not need transformers, but for best soundless performance with long cable lengths, use low impedance cables.
  • A direct box, also called DI-box (Direct input), is another type of impedance matching transformer that you can use. DI boxes are mainly used to connect unbalanced musical instruments and microphones to balanced sound mixers and other components.
  • Creating your own cables without a complete understanding of high and low impedance connections will cause poor audio output or no output at all. An audio workshop can create the right cables for you.
  • Plugging direct-connect transformers directly into components can damage the contacts of the transformer or component due to the weight of the auxiliary transformer. Always use a short extension cable to connect the transformer to components.
  • Always use shielded audio cables for all audio connections except speakers, as speakers need unshielded cable with a thicker diameter than shielded cables. Using shielded cables for speakers or unshielded cables for connections without speakers will cause interference and possible damage to the device.
  • The most reliable way to convert an unbalanced sound line to a balanced sound line is with an impedance matching transformer, also called a line matching transformer. Many modern professional audio components require the use of balanced audio lines due to the benefits of longer cable lengths and quieter operation. However, some older components, or those intended for consumer use, use unbalanced lines. A ‘line’ is a term that means a cable connection between components. Balanced articulated cables use 3-wire connectors, while unbalanced articulated cables use 2-wire connectors.