The 4020 Retro EQ is a four-band equalizer combined with complementary high-pass and low-pass filters designed to deliver a smooth, vintage character. Its high-frequency and low-frequency bands feature shelving EQs, while the mid-frequency bands provide parametric EQ control. Each band employs a gain-dependent variable slope and Q system, enhancing frequency selectivity during boost or cut for a refined sound. The filters utilize a split-octave design, offering slopes that range up to 24 dB per octave, allowing precise shaping of the audio signal.

This EQ is part of a collection of plug-ins that incorporate a unique output stage designed by McDSP, which adds a subtle transformer-like coloration to the audio. Alongside analog saturation modeling, this feature enriches the sound with analog warmth without directly emulating any specific classic hardware. The 4020 Retro EQ’s transparent yet vintage tone makes it suitable for enhancing various elements in a mix, such as adding fullness to drum tracks, adding depth and weight to bass lines, or polishing vocals to help them stand out.

The 4020 Retro EQ offers zero-latency processing with double precision, supporting both mono and stereo operation. Its flexible filter designs and unique algorithms provide precise control while maintaining musicality and warmth. With a range of presets developed by experienced mix engineers, this EQ is crafted to meet professional mixing needs across multiple genres, delivering character and clarity to any audio source.