Lijnniveau

Line niveau, or line level, is a standard signal level used for interconnecting audio devices. It sits between microphone level and speaker or amplifier levels, enabling signals to be passed through racks, mixers, and consumer electronics without excessive gain or loss. In practice, line level refers to the nominal voltage of the signal at the output of a source and the input of a destination.

Two common reference levels are used: consumer line level at about -10 dBV (0.316 V rms) and professional line level at about +4 dBu (1.23 V rms). The dBu reference uses a 0.775 V RMS reference; dBV uses 1 V RMS. Accordingly, professional equipment expects a hotter signal than most consumer gear. Some devices specify nominal line levels in decibels relative to these references, and adapters exist to match levels.

Line connections are designed for relatively low impedance sources and high impedance inputs. Line inputs typically present high impedance (tens of kilohms or more) and accept unbalanced (RCA, 3.5 mm) or balanced (XLR, TRS) connections. Balanced lines offer better noise rejection over longer cables.

Typical use includes feeding a DAC, CD player, audio interface, mixer, or preamplifier line input from another line output. When connecting devices with incompatible levels, a pad or attenuator, or a DI/buffer might be used to prevent clipping or excessive noise.