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Realtek 5.1 to stereo downmix = center and LFE in mutual exclusion

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Dec 19, 2007
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Hi.
I'm using this really convenient Realtek repackaged driver: https://github.com/pal1000/Realtek-UAD-generic/releases
Windows 10 x64, 1903, lastest updates installed.

I have only ONE problem so I ask for your help to solve it.
With my old X-Fi there's no problem at all, so it's something about Realtek hidden configuration/management of the audio channels downmix.

I always downmix a 5.1 configuration (enabled in Windows to achieve compatibility with 5.1 games audio) to my stereo headphones so I untick in the Windows Mixer all the missing speakers (rear/side speakers, center and the subwoofer) and force a full range output through the front left and right.

Doing so I loose the LFE/subwoofer signal in the windows test (and other self made test with OcenAudio), there's no audio at all and the volume meter too is dead: NO SOUND is routed from the LFE channel to the front L+R but Center is routed right.

Enabling in the Realtek Console the Center/LFE swapping gives me back the LFE signal AND sound.....but I loose the Center (no meter, no audio).

How can I have both? Thanks!

Using "Spatial Sound Card" ( https://spatialsoundcard.com/ ) I can bypass the problem but still I would prefer to use only the Realtek package to obtain the right downmix.
Thanks.

Anybody? Must be a really common issue in downmixing Realtek 5.1/7.1
 
Last edited:
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System Name Dell Inspiron 7375
Processor AMD Ryzen™ 7 2700U Mobile Processor with Radeon™ RX Vega 10 Graphics
Memory 16GB (total) 2400MHz DDR4 SODIMM
Video Card(s) Radeon™ RX Vega 10 Graphics
Storage SanDisk X600 SATA SSD 512GB
Display(s) BOE NV13FHM
Audio Device(s) Realtek ALC3253 (Dell Labelling) ALC255 (Real name)
A standard downmix always remove LFE channel. Both Dolby and DTS require so, and their downmixers also do so. LFE= Low Frequency EFFECTS.
LFE channel's purpose is for feeling the sound. By default, LFE signal was for bass that rattles. This signal is dedicated to the LFE speaker. Other channels are called full range audio, meaning that bass meant to be mainly heard was allowed in any channel.
On downmixing, the LFE channel is removed as there is no special LFE speaker in Stereo.
Thus the action you see is by design.
 

FordGT90Concept

"I go fast!1!11!1!"
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"Full range speaker" always disables LFE.

Make sure the orange cable is plugged in to the *correct* orange port on the motherboard (not digital). Usually it's Green/Black/Orange on one row. Digital is usually on the second or third row.
 
Joined
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I'm using stereo headphones to downmix to, not a 5.1 system (so not a cable problem).
"5.1" is needed in Windows Mixer to avoid incompatibility with recent (>2010) games, it's why I do NOT choose "stereo" as defaul setting.

Creative X-Fi LFE/subwoofer is routed to the stereo headphones with full or not full range speaker.
Just run the speaker test and here it is.
Maybe not by design as CityCultivator says but I really enjoy the solution and I would reproduce it on a Realtek.
 

FordGT90Concept

"I go fast!1!11!1!"
Joined
Oct 13, 2008
Messages
26,259 (4.63/day)
Location
IA, USA
System Name BY-2021
Processor AMD Ryzen 7 5800X (65w eco profile)
Motherboard MSI B550 Gaming Plus
Cooling Scythe Mugen (rev 5)
Memory 2 x Kingston HyperX DDR4-3200 32 GiB
Video Card(s) AMD Radeon RX 7900 XT
Storage Samsung 980 Pro, Seagate Exos X20 TB 7200 RPM
Display(s) Nixeus NX-EDG274K (3840x2160@144 DP) + Samsung SyncMaster 906BW (1440x900@60 HDMI-DVI)
Case Coolermaster HAF 932 w/ USB 3.0 5.25" bay + USB 3.2 (A+C) 3.5" bay
Audio Device(s) Realtek ALC1150, Micca OriGen+
Power Supply Enermax Platimax 850w
Mouse Nixeus REVEL-X
Keyboard Tesoro Excalibur
Software Windows 10 Home 64-bit
Benchmark Scores Faster than the tortoise; slower than the hare.
Games downmix automatically (positional sound effects) and most games do a fantastic job at it.

If you're on Windows 10, you can also enable spatial sound:
 
Joined
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Messages
818 (0.39/day)
System Name Dell Inspiron 7375
Processor AMD Ryzen™ 7 2700U Mobile Processor with Radeon™ RX Vega 10 Graphics
Memory 16GB (total) 2400MHz DDR4 SODIMM
Video Card(s) Radeon™ RX Vega 10 Graphics
Storage SanDisk X600 SATA SSD 512GB
Display(s) BOE NV13FHM
Audio Device(s) Realtek ALC3253 (Dell Labelling) ALC255 (Real name)
I'm using stereo headphones to downmix to, not a 5.1 system (so not a cable problem).
"5.1" is needed in Windows Mixer to avoid incompatibility with recent (>2010) games, it's why I do NOT choose "stereo" as defaul setting.

Creative X-Fi LFE/subwoofer is routed to the stereo headphones with full or not full range speaker.
Just run the speaker test and here it is.
Maybe not by design as CityCultivator says but I really enjoy the solution and I would reproduce it on a Realtek.
You are downmixing surround audio to STEREO headphones. Standard behavior: remove LFE.
Audio enhancer behavior: varies. Most do insert the LFE channel.
Check audio enhancers on this forum. You could use Creative software on whatever hardware you currently have.
 
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