LFE Downmix into 2.0 on Ultra

tabata

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Hi @WiiM Team and @WiiM Support ,

I’m trying to create interest for a feature that:

1) isn’t provided elsewhere
2) would be super valuable to many users, even many who don’t even know it yet
3) that WiiM is uniquely capable of providing on existing hardware, and given their engineering talent
4) is actually about providing audio features and performance (rather than, say, all of the attention on the VU meters lately)

Please, please, please offer the ability to downmix LFE from multichannel sources into 2.0 output on the Ultra.

Before anyone goes any further, if you have a very bass-capable system that currently does not receive LFE: 1) Stream the Severance opening title theme on Spotify or Tidal Connect, 2) go onto your TV or streaming player and play the same theme by watching the start of an episode. The Spotify/Tidal version has the LFE mixed into the 2 channels, and it is incredible. It makes the hair on the back of my neck stand up. The video streaming version is very meh. Convinced? I certainly am.

Currently, anyone without a full-sized AVR cannot get a downmix of LFE into 2.0. AVRs are very expensive, large, and completely overkill for this task.

The Wiim Ultra no doubt has the processing power and the app control ability to offer the option of taking a 5.1 signal via HDMI, break it down, and add LFE to the L+R.

Before anyone starts saying, “but Dolby white papers say the LFE channel should be ditched in a 2.0 downmix.” Great, thanks, but that’s dumb! There are many full range speakers or sat+sub combos that would benefit by this, and that’s why so many AVRs offer downmixing the LFE into the 2.0. My system is a perfect example, and there are many others like it, and I don’t think people know how much information they’re missing on the LFE. WiiM would be heroes.

Or maybe the counter-argument is, “but you have to understand the LFE is a bass-boosted signal, often 10db higher than the mains, and that creates issues for combining them into one output.” Ok, but that’s completely surmountable. The Ultra has very powerful digital signal processing to manage that and prevent clipping. It could even offer a slider in the app for users to attenuate the LFE signal in relative terms to the mains so that we could fine tune the signal for the next device in the chain.

To be clear, I do not want the LFE broken out and put on the subwoofer output of the Ultra. That would completely defeat the purpose for me. I have a miniDSP SHD 2x4 processor that is vital to my system that would be downstream of the Ultra. In my 2.2 system, the SHD handles independent stereo time-alignment for my two subs, my HPF and LPF crossovers, gain structure for my power amp, delays, Dirac Live correction, etc. It can only take a 2 channel input. The downmixed 2.0 with LFE needs to be available on the digital optical and coax outputs of the Ultra (huge, huge preference for digital output here), or on the two channel RCA outputs if for some reason that is the only workable method.

I already own the Ultra in a different 2.1 music-only system where it is my sole preamp (and where I’m using the Ultra’s sub output), but I would absolutely 100% buy another Ultra for my 2.2 home theater system simply for it to perform a single task: taking a multichannel source and adding LFE to the 2.0 output. That’s how bad I want it, and how limited the options are elsewhere.

So many people don’t know what they’re missing because they aren’t even aware of what’s being stripped out, or even if they are aware it’s happening, they downplay the difference it would make. This is a chance for WiiM to offer something unique and that opens people’s eyes. I think experiences like that are the core of WiiM’s appeal, and why I’m such a fan. Thank you!
 
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Yes, a beautiful dream. You defined the three points exactly. And maybe it won't be just a dream if Wiim seizes a great business opportunity. I agree with @Inertiaman that it's definitely not a fringe use, which to me is incomprehensibly ignored by most manufacturers and is a gap in the market.

Definitely not fringe, and call me crazy, but I think it would get a lot of attention if @WiiM Team do it, e.g Youtubers hyperventilating about how it’s a “game changer” as they like to do.

There are a ton of HDMI input equipped two channel pre-amp streamers out there (e.g. Bluesound, NAD, EverSolo, Cambridge, the list goes on and on), but none of them provide LFE downmix into 2.0. There’s a ton of audio guys now with subwoofers in their stereo systems — more than ever, it’s a huge growth area — who are using ARC downmixed into stereo for shows and movies and they aren’t getting the deep bass from LFE. If Wiim does this, it’ll be a big deal!
 
I got here googling the same requirement. I own a Mini which is great for feeding my DAC with a clean Spotify bitstream.

If WiiM Ultra could downmix LFE, I would buy it immediately. As others have noted, I too believe that there is a gap in the market, for a device that will do what the OP asks.

Movies from my 2 speakers and well integrated subwoofer sound significantly better when the downmix is not done by the TV; but instead it is done by the Jellyfin server (which gives some great options on how to downmix, too) or by the Nova player on the TV (the latter does include LFE too, as my tests have revealed).

Arguably, the TV might be botching the job of downmixing on more levels than just discarding the LFE (per the, by now and somehow, "official" guidelines). Regardless, I think it is confirmed that including LFE to a capable system does sound better.

The only hardware alternative at the moment, and only solution to e.g., enjoying Netflix's DD+ audio track - which, if nothing else, seems to have higher dynamic range than its stereo alternative - is to buy an AVR (and if you already have a better amp than it, use the AVR only and simply to achieve a hardware downmix).
 
I have given up on WiiM for subwoofer / LFE and bought an AVR. Really frustrating that this single missing feature made the WiiM Ultra unsuitable for my setup. I’ll be selling my Ultra and I’m considering getting rid of the multiple other WiiM devices throughout my house.
 
I have given up on WiiM for subwoofer / LFE and bought an AVR. Really frustrating that this single missing feature made the WiiM Ultra unsuitable for my setup. I’ll be selling my Ultra and I’m considering getting rid of the multiple other WiiM devices throughout my house.

Just keep the Wiim as a streamer. All other streamers will be the same.

Also if you don't have a subwoofer with your AVR, it'll discard the LFE signal also.
 
Just keep the Wiim as a streamer. All other streamers will be the same.

Also if you don't have a subwoofer with your AVR, it'll discard the LFE signal also.
Ultra is overkill just for a streamer, but I may stick with a few Wiim Minis or Pros for streaming and multiroom. Just a shame that the LFE can't be mixed down otherwise the Ultra would be a near perfect device for 2.1 stereo and home theatre.

I have multiple subwoofers connected to my AVR now and all LFE is being mixed down perfectly. I've gone all in with a Denon X3800H ex-demo AVR that I got for a bargain and I am in the process of building out a 7.2.4 Atmos system.
 
Ultra is overkill just for a streamer, but I may stick with a few Wiim Minis or Pros for streaming and multiroom. Just a shame that the LFE can't be mixed down otherwise the Ultra would be a near perfect device for 2.1 stereo and home theatre.

I have multiple subwoofers connected to my AVR now and all LFE is being mixed down perfectly. I've gone all in with a Denon X3800H ex-demo AVR that I got for a bargain and I am in the process of building out a 7.2.4 Atmos system.

It's pretty obvious from the outset a stereo streamer product won't offer the capabilities of a AVR.
Room correction with independent subwoofer EQ, and EQ like Dirac additional purchase
HDMI multiple input & output , with video bypass and OSD
Dolby Digital, DTS and variants decoding upmixing and downmixing
Multiple independent subwoofer outputs

So I wouldn't have bought a Wiim product hoping LFE downmixing would be added later. You should buy a product with features it has now, not hoping features you need are added later- as would be disappointed.

No issues with the Wiim Ultra I have, I use it as streamer and L/R speaker PEQ features, Squeezelite
 
It's pretty obvious from the outset a stereo streamer product won't offer the capabilities of a AVR.
Room correction with independent subwoofer EQ, and EQ like Dirac additional purchase
HDMI multiple input & output , with video bypass and OSD
Dolby Digital, DTS and variants decoding upmixing and downmixing
Multiple independent subwoofer outputs

So I wouldn't have bought a Wiim product hoping LFE downmixing would be added later. You should buy a product with features it has now, not hoping features you need are added later- as would be disappointed.

No issues with the Wiim Ultra I have, I use it as streamer and L/R speaker PEQ features, Squeezelite
Thanks champ, I never said I wanted the capabilities of an AVR, and I didn't buy the Ultra hoping LFE downmixing would be added later.

I bought the Ultra just wanting to replace the streaming capability on my KEF LS50 Wireless IIs, which is garbage. And I thought it could function for me as a pre-amp with some other useful features. Not being a home theater expert, I incorrectly assumed that the bass management feature meant that the LFE channel from 4K blu-rays would get downmixed for 2.1, rather than just being discarded.

I, like others in this thread, am simply saying that it's a shame the Ultra can't downmix the LFE channel, because it would otherwise have ticked a lot of boxes for my use case. As it stands, it doesn't, and I have replaced it with an AVR.
 
I use downmix feature in Infuse app on Apple TV and I must admit it makes difference, I even sometimes prefere to used it over official apps of major streaming platforms.

There are similar apps with such capabilities (like Kodi) but having it on wiim would make it system wide and app independent.

I assume above apps use some kind software solutions (supported by hardware of coz). If so, it should be implementable through wiim firmware development.

I agree to firstly, one should look for devices with this capabilities implemented natively but i don’t see anything wrong in proposing this as welcome and for many very useful feature as part of product development.
 
It should be noted that twith properly mixed programme material the LFE should only provide additional effects. All essential content should be included into the front channels. In particular, the front channels are not limited in frequency response. They may well contain 20 Hz (or lower) signals.

Always downmixing the LFE into a stereo output (subwoofer or not doesn't matter, it's just a matter of routing) would be wrong. The LFE was invented to add louder bass output to existing cinema systems and a stereo setup might or might not be able to cope with that. But adding the option to do so would be useful.

Downmixing does require support for the specific multi-channel format, of course. So far WiiM only support Dolby Digital (AC-3).
 
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