The Importance of Surround and Height Speakers for Atmos Music

Installing an immersive audio system for Atmos music can certainly be done on the cheap, but members of the Audiophile Style community are usually willing to spend a bit more to get better sound quality, as long as it makes sense. When it comes to Atmos music, finding what makes sense is the hard part. One of my goals with my Atmos music system, is to educate people and give them information they can use to decide for themselves. 

I absolutely think every speaker in my 7.1.4 system matters immensely. I'd previously thought about installing speakers much less capable than the Wilson Audio Alidas, at least for height channels, but I'm thrilled I elected to go with my gut on this one, and install the best speakers I could for all the surround and height channels. Members of this community can take my word for it, or listen to excerpts below, that provide examples of why I think every surround and height channel is critical for Atmos music. 

Key Questions

As audiophiles think about Atmos music, trying to create a hierarchy of component importance, and figure out what really matters to us, a couple questions seem to be the most critical. First, does it makes sense to install high end speakers for surround channels? Second, are the height channels really important or even used very much? 

The answer everyone wants to hear is, of course one can use inexpensive "acoustic wallpaper" for surrounds, throw a few Monoprice satellites up on the ceiling, and call it a day. Unfortunately, the laws of physics still apply to even the most nonconformist of audiophiles. Speaker design, drivers, enclosures and product support, all matter. To show people that this all matters, at least to me and likely to most audiophiles, I've created some videos. The videos are simple illustrations, that both show visually and audibly, the importance (or lack there of for some people), of surround and height channels in an Atmos music system. 

In an unscientific fashion, I setup my iPhone 12 Pro to record video of my Merging technologies Anubis Premium, while recording the sounds from my 7.1.4 Atmos music system. To see how the system performs objectively and subjectively, here's a detailed article (link). Both the iPhone and Anubis were on a table immediately next to my listening chair. The iPhone 12 Pro's internal microphone was used because this exercise isn't about absolutely fidelity. The only way to really experience this system's potential is to sit in the chair and press play. 

The video of my Merging Anubis is nice because it displays the music in each channel, relative to the other channels. What I mean by this is, if I only showed the audio in surround and height channels, but not in the main or center channel, it could be very misleading. If the surround and height channel audio is present, but down by 50 dB from the main speakers, it's far less critical than if it's around the same volume level. 

My Merging Anubis screen displays both a CAPS 20 (Windows 11 PC) and MacBook Pro as sources. Under the Monitors section, my Atmos system is listed as the output. The MacBook is highlighted because that's the source I used for playback. In very small letters, above the word MacBook, one can see L R C LFE Sl Sr Ls Rs Tl Tr Trl Trr for the 12 channels in my Atmos music system. Above each letter(s) is the musical content being sent from the MacBook to the Anubis. Above the corresponding letters over the Atmos output on the right, is the same musical content, but at a lower volume because I like to save my ears and turn the volume down a bit. 

Speaking of volume, -15 dB is a pretty "normal" level in my system, I often listen low and higher, depending n the content. I selected this level as a happy medium.

Last, I could've spent much less time by just extracting the audio from the surround and height channels, and posting them as WAV files, but that would've provide the entire picture. Or at least, not the picture I believe will help people on their way to Atmos music or not. 

Technical note: The videos below were created by combining two separate video and audio captures. This is because convolution filters cause the Anubis to display the audio correctly, but with dB subtracted here and there. The audio captured when using the convolution filter is correct, as it's what I hear at the listening position, but the Anubis display isn't accurate because it doesn't display what's heard in this case. So, I captured the Anubis video without using convolution, then added the audio with convolution, to show what it looks and sounds like accurately. The convolution filter enables the listener to hear the album as it was intended by the "artist" which is what is shown on the display when you see it without the filter. 

Perhaps an example is helpful: If the front channels are reduced by 25 dB (example only) in a convolution filter, they will appear 25 dB down on the Anubis display. However, they would be reduced by 25 dB only to correct for an issue. Once corrected by 25 dB, the audio would sound just like the actual album because without the filter, there'd be a 25 dB boost caused by at the room, that wasn't in the album.

Sounds convoluted I know, but this is how it works. I can explain more in the comments if needed. 

Let The Show Begin

Here we go with the first portion of a track. I only recorded partial tracks because that's all that's really necessary to show what I'm talking about and I like to stay within the bounds of copyright law, whatever that means.

Elton John - Rocket Man (Surround and Height Channels Only)

Here is the first couple minutes of the track that has everyone in the music business talking. However, I muted the front Left, Center, and Right channels for this recording. What's on the video is only the surround, LFE, and height channels. Even I was surprised to hear all the content that's in the surrounds and heights, in the first minute of the track. At about 58 seconds into the track, the mix turns legendary. Side and rear channels are used even more, to great effect. Have a look and listen. Remember, this is only the surround, height, and LFE channels in the audio recording. Nothing from the front left, right, or center. 

Aretha Franklin - Amazing Grace (Live 1972) (Surround and Height Channels Only)

This is a fantastic album, recorded live at the New Temple Missionary Baptist Church, Los Angeles 01/13/1972. With the front left, center, and right channels muted, one can really hear the audience and Aretha's voice as it was reverberating around the church. One important item here is how close in volume many of the channels are, according to the Anubis display. The center (muted) and top left and top right are definitely used in this mix, more than many of the other speakers. This is a fantastic track that I wish everyone could hear in its entirety. 

Beatles - Come Together (Surround and Height Channels Only)

I know many people have never heard this track. Only kidding. Giles Martin mixed this one really well, using all the channels. The front right, center, and left are more present in much of the mix, but the surround and heights are absolutely critical. Have a listen to what's in the surround, height, and LFE channels only. It isn't just a little reverb. 

Billie Eilish - Bad Guy (Surround and Height Channels Only)

Here's a pop song that I really like. The Atmos mix uses all the channels, while focusing mostly on the front right and left (as seen on the Anubis display). I'd say much of the audio in the surrounds and heights is fill-in, that ads to the immersive presentation. 

Fleetwood Mac - Gold Dust Woman (Surround and Height Channels Only)

Another classic we've all heard a million times. I never get sick of this track. While Stevie's vocal is mainly in the front channels (muted), she can be heard in the other channels. Other audio is much more apparent in the surrounds, especially at 1:20 into the video when Christine McVie's vocals are in the height channels. This really solidifies the importance of good height channels.