The Equalizers submenu contains three standard multi-band equalizers (they work in exactly the same way as the graphic equalizers on your hifi equipment), as well as a collection of specialized equalizers aimed at the restoration of old vinyl recordings. These specialized equalizers are described in this section.
The RIAA Reproduction filter allows you to compensate for the standard RIAA filter usually applied on vinyl recordings. See for example http://www.bonavolta.ch/hobby/en/audio/riaa.htm for more information. In general, vinyl recordings are engraved with reduced bass levels and increased treble levels. In 1954, the RIAA (Recording Industry Association of America) introduced a standard filter that was used on nearly all phonograph recordings since then. The RIAA Reproduction filter allows you to apply the RIAA curve to a recording. This is usually done by the turntable preamplifier. It may however be useful if you connect a turntable directly to your computer or use a normal preamplifier.
The Inverse RIAA Reproduction filter applies the inverse of the RIAA curve to a recording. This is useful for undoing the effect of a turntable preamplifier on acoustic LP recordings that were not engraved with the RIAA curve.
The RIAA/IEC Reproduction and Inverse RIAA/IEC Reproduction filters work in a similar way, except that they use a modification of the original RIAA curve that was introduced around 1976 but is not as widespread.
The LP / 78rpm Equalizer is a parametric equalizer that is designed to allow the reproduction of old vinyl recordings. It contains a number of presets for leading manufacturers. More information can be found for example at
If the recording is made through a standard turntable preamplifier, RIAA de-emphasis should be enabled in order to compensate for the RIAA curve.
