4.4 mm Balanced Line Input
A 4.4 mm balanced line-input count states how many suitable sockets receive balanced analogue line-level audio.
The connector receives a source signal rather than driving headphones. Its direction and wiring are therefore essential parts of the specification.
4.4 mm Balanced Line Input — Headphone Amp
On a headphone amplifier, this input can connect a compatible balanced line output from a DAC or other source. The source and cable must use the supported signal assignment and provide an appropriate line level.
Compare the input requirements with the source’s actual output mode and wiring. A 4.4 mm balanced headphone output is not automatically equivalent to a balanced line output, despite the matching plug size. Keep this count separate from headphone sockets and other balanced inputs, and check signal level before assuming that physical fit establishes compatibility.