A balanced connection sends the signal twice, once inverted, and the receiving end cancels anything picked up along the way. That is why an XLR or TRS run can cross a room without humming and an instrument cable cannot.
How the cancellation works
Two conductors carry the same signal with opposite polarity. Interference hits both equally, and flipping one back at the receiving end cancels it while the wanted signal doubles.
Where it matters most
Long runs, rooms full of power supplies and screens, and microphone level signals, which are tiny and easily swamped.
Where it does not
A guitar into an amp a meter away. That connection is unbalanced by design, and the instrument’s own output impedance matters more than the cable type.
Check your own manual before you plug anything in. Voltage, polarity and current draw differ from model to model, and the manufacturer’s figures take precedence over anything written here. A supply of the wrong polarity can damage a pedal in seconds, phantom power is safe for most microphones but not for every one, and the required voltage is printed next to the socket or stated in the manual — not inferred from a connector that happens to fit.
The questions players ask
Which cables are balanced?
XLR and TRS — two rings on the plug. TS, with one ring, is unbalanced and is what instruments use.
Does balanced sound better?
Not on its own. It rejects interference, which matters over distance and beside power cables. Over a short desk run the difference is often inaudible.
Last reviewed 2026-08-18