iMac Sound Quality Driver for Windows 7

iMac Sound Quality Driver for Windows 7 Image
Improve sound quality for iMac computers under Windows 7

iMac computers, when used with Windows operating system - have very bad quality of sound playback (tube-like resonance). This is because Mac OS X operating system contains adjustment filters to compensate for speaker response, while Windows does not.

This driver aims to provide these correction curves and improve sound quality on Windows.

If somebody from either Apple or Realtek would agree to embed this technology into Windows soundcard drivers, I would gladly supply the source code and assist in all ways with the driver integration free of charge. Since Realtek drivers already have some sort of sound panel with the equalizer, which utilizes very similar principles to this correction driver, this integration should be relatively a minor task and should be a minor extension to their LFX effect code.


Before installing this driver, please check that a Microphone playback is switched off.

(If after tapping computer on the top, the tap is immediately heard back from the speakers - then it is a sure sign that the microphone is not muted and may create an unpleasant resonance in the sound.)

To switch the microphone off:

  1. Right click on the speaker icon in the system tray
  2. Select: Recording devices
  3. Right click on the Microphone, select Properties.
  4. On the Listen tab, "Listen to this device" should be unchecked.
  5. On "Levels" tab, the blue speaker button should display a small red crossed circle, signifying that it is muted.

After this is performed, please unpack the archive, run the executable from it and follow the on-screen instructions.


This driver was made using measurements taken from aluminium 24" iMac. This driver will not properly adjust the sound on MacBooks, and sound adjustments for other iMac models might not be optimal.

This driver was written only for Windows 7. Both 32-bit and 64-bit versions are supported.

The side effect of installing this driver is that:

  • All DRM audio will be disabled, such as music from Microsoft URGE store, and Blu-ray discs.
  • However Music from iTunes store will still work.
  • Standard RealTek audio effects will not be available. Settings such as environment, reverberation and equalization will disappear.
  • This fix might be incompatible with 3rd party sound changing effects software, such as pitch shifting, voice morphing, etc.

Technical information

This program will install an LFX system audio effect with a long chain of equalization and modify the  egistry to replace the standard RealTek and Microsoft driver effects.

The file MacFixAPOLFX.dll will be copied to the Windows system folder and registered as an audio object.

The technology which is used to create this driver is described on this Microsoft's page: