[Matt Gore]

Using audio processing objects (APOs) in Windows is possible since Vista. Those provide customizable, software-based digital signal processing (DSP). A freeware called Equalizer APO makes use of that infrastructure and allows to real-time-convolve 7.1 input sounds down to binaural stereo audio for headphones.
This tool works nealy without using any CPU power, latency free and the kind of convolution you want to use is customizable. I have currently recorded or collected impulse responses of:

• Dolby Atmos Headphone
• CMSS-3D
• SBX Pro Studio Surround (formerly THX TruStudio Pro Surround)
• Dolby Headphone
• Sennheiser GSX Binaural 7.1
• DTS Headphone:X
• Windows Sonic Headphone
• Dolby Home Theater v4 Headphone Surround Virtualizer
• Razer Surround
• Out Of Your Head
• HRTFs/HRIRs from IRCAM, CIAIR, KEMAR MIT and OpenAL

Guide:

1. Download Equalizer APO.

2. The program will ask you to configure your playback device. Tick the box in front of the port where your headphones are connected to and finalize the installation. (But do not reboot.)

3. Instead of rebooting, press Win+R and paste the following into the opened window:

powershell -Command "Start-Process cmd -ArgumentList '/c "net stop Audiosrv && net start Audiosrv && mmsys.cpl"' -Verb RunAs

4. The sound preferences should open soon. First click on your device, then onto the lower right "Properties" button of the previous window and change Advanced - "Default Format" to 48000Hz. Save with "OK".

5. Click on "Configure" in the lower left of the previous window. Select "7.1 Surround" and continue till the window closes. (Skip to the last step if you could select 7.1 or continue with 5a if it didn't work [e.g. with some DACs or DP/HDMI audio].)

- 5a. Download and install Voicemeeter, reboot.

- 5b. Open Virtual IO Control Panel from your start menu and click Options - "Internal Sampling Rate: 48000Hz". Open Voicemeeter and also select 48000Hz in Menu - "System settings / Options" - "Preferred Main SampleRate".

- 5c. Open "mmsys.cpl" again (that's the sound preferences window from step 4) and change Advanced - "Default Format" to 48000Hz in the "Properties of VoiceMeeter Input" window. Open also the preferences of your speakers and tick both boxes below Advanced - "Exclusive Mode". Reboot again.

- 5d. Open EQ APO's Configurator.exe, select "Output A1" and remove the check mark you made earlier. Redo step 3.

- 5e. Launch Voicemeeter and select your output device as "Hardware Out" - "WDM: Speaker (Soundcard)". Mark Menu - "Hook Volume Keys (For Level Output A1)" and Menu - "System Tray (Run at Startup)". You can now safely close this window.

6. Download this archive and extract it into %ProgramFiles%\EqualizerAPO\config (a file called "config.txt" should be overwritten). Now you are ready to go!

Simply changing between stereo and 7.1 in Windows will de- and reactivate the sound processing.
You can use a different virtualization by replacing "hrir\atmos.wav" in line 5 of the config.txt with something else from the hrir folder (change everything to 44100Hz when using "ciair.wav", "irc.wav" or "mit.wav").

You can of course create filters and more stuff for your audio output, simply check out EQ APO's configuration reference or play around with its "Editor.exe".

Originally shared on reddit.

 

[Mr Trev]

Tried this, can't get it to work without excessive static and sound break up. If I max out the latency in Virtual IO, I can minimize the noise, but never get rid of it

Can you clarify what you mean in step 5d when you say "remove the cross"?

 

[Matt Gore]

Tried this, can't get it to work without excessive static and sound break up. If I max out the latency in Virtual IO, I can minimize the noise, but never get rid of it

Can you clarify what you mean in step 5d when you say "remove the cross"?

Equalizer APO doesn't seem to work completely flawless with Voicemeeter. But the support for it came just recently so you might want to wait for the next EQ APO update or try one of the many possible solutions on reddit. (Open the Configurator, deactivate Output A1, restart Windows Audio, reactivate it again, maybe even while playing music in the background. Or change every sampling rate to something and then back to 48kHz again.)

Oh, it is a check mark you had to make in step 2, not a cross.

 

[Mr Trev]

Been fiddling with all the latency settings, WDM/ASIO, on both the internal laptop card (cheap-ass realtek) and a USB DAC (Fiio X3). Nothing I tried could make the popping go away. The best I could do was max out the latency/buffer for both IO control panel and Voicemeeter (on board sound - nothing changed regardless of the settings using my usb dac via asio). This got the popping down to a "tolerable" level, at least enough to find out this doesn't really work for me to begin with. I was testing with Dishonored, and voices from distant people still sounded like they were right next to me. I didn't try all the filters, but the ones I tried didn't offer much of an improvement over stereo

 

[Matt Gore]

Seems like EQ APO isn't working correctly. The only option I could think of instead of waiting for an update/fix would be to not use VoiceMeeter and instead only Equalizer APO with your internal sound card. In the games you would want surround you would then have to plug your headphones into Realtek. Use your Fiio for everything else.

 

[Mr Trev]

Being a sucker for punishment, I tried doing another clean install and did manage things working for the Fiio. Didn't have to tweak anything, the only pops happen when I "test" the device, right at the beginning of the tones. The sound is fine in game. Only works for WDM though, ASIO still crackles like crazy.
Can't get the on board sound to work properly however. I really am not surprised, my laptop has an absolute s**t sound card (realtek really cheaped out on this one), and the Win 10 drivers/implementation (I'd like to ditch SST altogether and use the basic drivers) is beyond horrible - I have a feeling if I was running Win 7 it probably wouldn't be an issue. I also wouldn't be able to use Equalizer APO alone because the onboard sound is limited to stereo.
Trying some of the other filters and so far OpenAL seems to give me the best results.

 

[Lunar Eclipse]

Hey @Matt Gore Thank you for this sweet vss setup! I have been using HeSuVi for the better part of 2018 and find it absolutely indespensible. I just discovered the 44khz hrir's. These now allow me to use my Earstudio & HeSuVi together in wireless mode. For some reason w10 locks the ES aptx mode to 44. Eventually, I hope to find a solution of having to occasionally reset the audio in voicemeeter when sound sputters and drops. No biggie. I will probably use this solution with my mobius as well, just to have more surround choice. Wireless HeSuVi is truly where it's at. Thank you again