Available for download, the AUDIFIED RZ062 is an emulation of two rare, vintage equalizers used throughout Europe in the 1960s: the Klangfilm RZ062a valve EQ, and its sibling, the RZ062b. Both EQs sport controls to adjust bass and treble, giving you the power to boost and attenuate the lows and the highs. Each plug-in also provides input and output knobs as well as a calibration section for tailoring the harmonic saturation. On stereo sources, you can stereo-link the EQ or manipulate the EQ signal in mid/side mode, which comes in handy during mastering.
Where each of the plug-ins differ, however, is in their midrange control. The midrange knob on the RZ062a pivots the entire frequency response around the preset midrange curve, which is centered on 650 Hz. As a result, this knob simultaneously lowers the bottom end as it raises the treble, and vice versa. On the RZ062b, you’ll find four selectable frequency centers, and the ability to boost or cut their presence in a smooth, pleasing manner.
As these plug-ins were modeled on two separate hardware units, they do have subtly different flavors. Even when set to unity gain, they do not pass null tests at identical settings on identical mixes. In other words, this is to your benefit. Even though these EQs ostensibly share everything besides the midrange controls, their minute differences—borne from careful modeling and sampling of independent units in their construction—essentially give you two EQs in one package. You can use this to your advantage when mixing tracks, even when you're only making use of the highs and the lows, because slight tonal variances from the circuit modeling help replicate the subtle non-linearity of analog hardware. These plug-ins are compatible with Mac and Windows operating systems. They can operate in AU, RTAS, VST, and AAX formats, and in 32- or 64-bit systems.