Dolby Digital 5.1 - No subwoofer signal

Persona Grata

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Two Sound Lite purchased and setup as Dolby Digital 5.1 with Surround Right (SR) and Left (SL) via the WiiM Ultra. Subwoofer connected to the Ultra.

Using an Apple TV 4K connected via ARC to my LG TV. Both surround back channels work fine, but there is no subwoofer (LFE) output. Zero. In 2.1 setup the sub works fine. I have tried all kinds of settings both in the TV and the Apple TV box with no luck. I’m using subwoofer crossover. Hm, may there’s something there.

Please advise.
 
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Two Sound Lite purchased and setup as Dolby Digital 5.1 with Surround Right (SR) and Left (SL) via the WiiM Ultra. Subwoofer connected to the Ultra.

Using an Apple TV 4K connected via ARC to my LG TV. Both surround back channels work fine, but there is no subwoofer (LFE) output. Zero. In 2.1 setup the sub works fine. I have tried all kinds of settings both in the TV and the Apple TV box with no luck.
Please advise.

The Wiims don't pass LFE soundtrack.

Buy a AVR.
 
That’s a big disappointment. Then the whole sale concept of support for Dolby Digital 5.1 falls apart.
One should at least be able to send the full audio signal to the sub, but even bypass mode doesn’t work.
 
That’s a big disappointment. Then the whole sale concept of support for Dolby Digital 5.1 falls apart.
One should at least be able to send the full audio signal to the sub, but even bypass mode doesn’t work.

And not even decoding and downsizing DTS or Atmos

They're stereo products which for that they are good but until they match what a avr does shouldn't really try and sell them as bodge job AV products
 
The Wiims don't pass LFE soundtrack.

Buy a AVR.
That's not correct.

See:


 
That's not correct.

See:


That’s exactly what I read too, but I get zero signal out to my sub trying all the suggestions in the online manual.
 
That’s exactly what I read too, but I get zero signal out to my sub trying all the suggestions in the online manual.
I acknowlege yor issue. I just wanted to point out what is not a reason for that.

Handling of the LFE and routing of bass frequencies to a subwoofer are two totally different subjects. In other words: Even if the LFE wasn't included in the mix you should still get output from the subwoofer, since the other channels (in particular the main channels FL and FR) do include bass information, of course.

Does your Apple TV really output Dolby Digital (AC3), not any of the unsupported newer formats?

Does it make a difference if the input is stereo or DD? Does the issue go away when you unpair the Sound Lite speakers and use the Ultra on its own?

What are your subwoofer settings as defined in the WiiM Ultra?
 
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Thanks for trying to help. I get Dolby Audio 5.1 with AC3 1536 kbps 16-bit/48 kHz from the Apple TV 4k box with both auto and Dolby Digital 5.1 settings from the Apple TV but no signal out to the sub. I have set a crossover frequency at 52 Hz for HiFi-stereo listening. When in 5.1 I try both sub bypass mode and turning sub output off (!). Same result: no sub out. I have tried changing LG TV-settings from auto to Dolby Digital with same lack of sub-signal. I can change the TV-output to PCM and get LPCM out but only in stereo and with sub signal. Same if I change to stereo out from Apple TV.
 
Thanks for trying to help. I get Dolby Audio 5.1 with AC3 1536 kbps 16-bit/48 kHz from the Apple TV 4k box with both auto and Dolby Digital 5.1 settings from the Apple TV but no signal out to the sub. I have set a crossover frequency at 52 Hz for HiFi-stereo listening. When in 5.1 I try both sub bypass mode and turning sub output off (!). Same result: no sub out. I have tried changing LG TV-settings from auto to Dolby Digital with same lack of sub-signal. I can change the TV-output to PCM and get LPCM out but only in stereo and with sub signal. Same if I change to stereo out from Apple TV.
I tested a 5.1ch group using Amp Ultra and WiiM Sound. I can hear deep bass from the subwoofer connected to Amp Ultra's Sub-out. However, the volume isn't very loud, so you might have missed it.(?)

I checked this during the fight scene starting at 6 minutes into Netflix's The Witcher Season 4, Episode 1.
1946.jpg
 
Thanks for trying to help. I get Dolby Audio 5.1 with AC3 1536 kbps 16-bit/48 kHz from the Apple TV 4k box with both auto and Dolby Digital 5.1 settings from the Apple TV but no signal out to the sub. I have set a crossover frequency at 52 Hz for HiFi-stereo listening. When in 5.1 I try both sub bypass mode and turning sub output off (!). Same result: no sub out. I have tried changing LG TV-settings from auto to Dolby Digital with same lack of sub-signal. I can change the TV-output to PCM and get LPCM out but only in stereo and with sub signal. Same if I change to stereo out from Apple TV.
1.5mb Dolby sounds like it's Atmos?

You need to disable DD+ output from your source.
 
Hi guys. Thanks for helping out. A little bit of experimentation goes a long way. The problem with no-sub seem to only affect native Apple TV content. If I set the TV to DTV Audio Setting: Auto and Digital Sound Output: Pass Through and Apple TV-setting to Sound Format: Dolby Digital 5.1 and Sound mode: 16-bit I get sub signal through both Disney+ and SkyShowtime. Interesting for sure. Hopefully Wiim and Apple will find a solution to this and also Airplay in the future.
 
Last thoughts from me. I can live with this combined home theater and hifi solution. It’s good enough for many I think.

Here’s a little tip for you if you have an Apple TV box and have initiated Dolby Digital 5.1 in sound format setting. Try some classical or jazz music from the Apple Music app marked Dolby Atmos. It used Apple Spatial Audio format (Atmos and Spatial is not the same). The two WiiM Sound as surround speakers will give you a nice acoustic room sound. Feels like you’re in the music hall. Very good.

If you have decent full ranging front speakers you’ll not miss the sub with this kind of music.
 
Hi guys. Thanks for helping out. A little bit of experimentation goes a long way. The problem with no-sub seem to only affect native Apple TV content. If I set the TV to DTV Audio Setting: Auto and Digital Sound Output: Pass Through and Apple TV-setting to Sound Format: Dolby Digital 5.1 and Sound mode: 16-bit I get sub signal through both Disney+ and SkyShowtime. Interesting for sure. Hopefully Wiim and Apple will find a solution to this and also Airplay in the future.
I'm not sure if I fully understood all the details because I neither use an Apple TV nor any of these services, but if you can reproduce the issue and there is no setting on the Apple side that would make the subwoofer play, it's probably still worth giving feedback to WiiM through the WiiM Home App.
 
Last thoughts from me. I can live with this combined home theater and hifi solution. It’s good enough for many I think.

Here’s a little tip for you if you have an Apple TV box and have initiated Dolby Digital 5.1 in sound format setting. Try some classical or jazz music from the Apple Music app marked Dolby Atmos. It used Apple Spatial Audio format (Atmos and Spatial is not the same). The two WiiM Sound as surround speakers will give you a nice acoustic room sound. Feels like you’re in the music hall. Very good.

If you have decent full ranging front speakers you’ll not miss the sub with this kind of music.

The standard AV & Stereo is

AVR with pre outs, L/R from the AVR into a stereo integrated amplifier/pre-amplifer HT Bypass input
Stereo sources connected to the stereo pre/integrated amp

Subwoofer connected to the AVR sub out.
In stereo mode, the AVR is off.
In AV mode, both are on, stereo amp is in HT bypass input, AVR controls master volume

Getting sub to work in AV & hifi is more tricky but in the above mode you'll get multi channel and hifi working, sub working in AVR mode, sub not functioning in hifi mode.
 
Yes, and then there's "non-standard AV & Stereo" where the stereo amplifier can do a better job integrating the sub for both, AV and Hi-Fi mode. A very common setup amongst users of avforums.com. :)
 
I tested a 5.1ch group using Amp Ultra and WiiM Sound. I can hear deep bass from the subwoofer connected to Amp Ultra's Sub-out. However, the volume isn't very loud, so you might have missed it.(?)

I checked this during the fight scene starting at 6 minutes into Netflix's The Witcher Season 4, Episode 1.
View attachment 32585

Need to test .1 LFE content. Probably have to use a DVD/BD test disc with specific speaker and .1 LFE tones to check nothing is being discarded.
 
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