Program Equalizer Algorithm

Featuring a unique architecture which effectively minimizes phase shift (with the capability of accurately reproducing an audio square wave, even during equalization!) and the industry's first and most appreciated "air band", the extremely rare program equalizers which are designed and manufactured in the mid 1990s have set the standard for modern program equalization. Besides being an indispensable tool for mixing and mastering (especially due to their inherent ability to transparently manipulate both the lowest and the highest ends of the frequency spectrum), the air band's smooth and breathy character has also made them the ultimate tool for equalizing vocal tracks. With its meticulously designed topology, the PEQ2 Algorithm accurately and efficiently simulates the earlier version of these units in the digital domain.

Key Features

  • Extremely High Processing Efficiency.
  • Supports sampling frequencies up to 384 kHz.
  • Clickless parameter update.
  • Proprietary topology which is optimized for low latency, low noise and high dynamic range.
  • Supports both 32 bit (single precision) and 64 bit (double precision) floating-point processing.
  • Clearly and concisely implemented in pure C++: portable to any platform that is supported by a C++ compiler.


PEQ2 Program Equalizer Algorithm features six bands. The first four peaking bands have the center frequencies 10 Hz (SUB), 40 Hz, 160 Hz and 650 Hz. Each band is 2.5 octaves wide. The fifth high frequency shelving band has a cutoff frequency of 2.5 kHz. The sixth "air" band is a -boost only- high frequency shelf with a cutoff frequency of 10 kHz. The amount of boost or attenuation is continuously variable from -15 dB to 15 dB on all bands except the air band which has an amount of boost that is continuously variable from 0 dB to 20 dB.


  • Software Plug-ins

  • Digital Audio Workstations

  • Digital Mixing Consoles

  • Hardware Effect Processors


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Copyright © 2005- Boğaç Topaktaş