Equalizer APO

Equalizer APO is a parametric / graphic equalizer for Windows. It is implemented
as an Audio Processing Object (APO) for the system effect infrastructure
introduced with Windows Vista.

Requirements:
- Windows Vista or later (Windows 7 - 11 have been tested)
- CPU architecture x64 (64 bit), x86 (32 bit) or ARM64 (on Windows 10/11)
- applications must not bypass the system effect infrastructure
(APIs like ASIO or WASAPI exclusive mode can't be used)

Equalizer APO can be used in conjunction with Room EQ Wizard (http://www.roomeqwizard.com/), because it can read its filter text file format.

Please have a look at the Wiki (http://sourceforge.net/p/equalizerapo/wiki/) for instructions on installation and configuration

Features

virtually unlimited number of filters
works on any number of channels
very low latency, which makes it suited for interactive applications
low CPU usage
modular graphical user interface
VST plugin support
integrates into Voicemeeter (http://www.voicemeeter.com/)

Project Samples

New graphical user interface added in version 1.0

The frequency response of the filter can be edited precisely and can have arbitrary shape

Project Activity

See All Activity >

License

GNU General Public License version 2.0 (GPLv2)

Follow Equalizer APO

Equalizer APO Web Site

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User Reviews

Filter Reviews:

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mjatanim Edited 2026-07-20

Awesome! Equalizer APO + Peace Equalizer + AutoEq (website for confiqs) is all you need for music listening at PC! 😄
m3thfac3 Edited 2026-06-28

Awsome for FPS Gamers! And the support is also amazing!!!

1 user found this review helpful.
filipe1607 Posted 2026-06-10

Best noise cancelling free software by FAR.
darthvegemite Posted 2026-06-03

Love APO EQ

1 user found this review helpful.
astonrs Posted 2026-05-14

Don't listen to the 1* reviews. The software is brilliant, works perfectly. I was using AudioEqualizer EQ on chrome and was temperamental at best. This is the nuts. bass is super clean and powerful with literally no distortion. 5 stars

1 user found this review helpful.

Additional Project Details

Operating Systems

Windows

Languages

English, German

Intended Audience

Advanced End Users, End Users/Desktop

User Interface

Non-interactive (Daemon), Qt

Programming Language

C++

Related Categories

C++ Sound Audio, C++ Home Theater PC Software

Registered

2012-09-13

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