I’ve been planning to upgrade my surround sound system to Dolby Atmos ever since the format was first announced for home use. Due to a variety of delays, some financial and some personal, I put off the installation of an Atmos-capable A/V receiver until after Christmas this year. Now, finally, the time has come to connect the new equipment and step up to the next generation of home theater audio!
I’ve explained the concept of Dolby Atmos in previous articles (here, here and here). For home theater purposes, the main takeaway is that Atmos fills your room with sound from two auditory planes. The format is built off a traditional base of 5.1 or 7.1 speakers at ear level, and then adds a second layer of sound from overhead. This can be achieved either by mounting additional speakers high in your room, or by using special “upfiring” Atmos-enabled speakers (or speaker modules) that project sounds from ground level to bounce off your ceiling.
The home theater version of Atmos is a flexible format that can accommodate a number of different configurations, from a minimum 5.1.2 layout (that’s 5.1 channels on the ground and 2 height channels) to a theoretical 24.1.10 discrete speakers. For both practical and financial reasons, support for really high speaker counts will be the domain of high-end, extremely expensive boutique products. The majority of current-generation Atmos receivers top out at 7.1.4. Realistically, that should be plenty, even for large home theater rooms.
Because I’m coming from a 7.1 system, I chose to go for a full 7.1.4 Atmos configuration. To do that, I needed two new pieces of gear (in addition to the new speakers, which I’ll get to shortly).
I’ve been a loyal Denon customer for many years, so the Denon AVR-X5200W receiver was a natural upgrade path. However, although it can decode up to 7.1.4 channels for Atmos, the receiver only has nine channels of built-in amplification. In order to power all eleven speakers, I also needed a separate two-channel external amp. For that, I went with the Emotiva UPA-200. Admittedly, that particular model is probably overkill just to drive a pair of height speakers. (The AudioSource AMP-100 is a popular, inexpensive alternative for that.) As such, I’ve decided to use the Emotiva amp to power my main front left and right speakers, while the amps in the receiver will handle everything else.
Honestly, buying a new receiver and amp was the easy part. Upgrading my speakers was more complicated for me. I’ve been pretty happy with the speakers that were already in my system, and had neither the desire nor the budget to replace all of them. Unfortunately, the manufacturer, Cambridge Soundworks, has suffered a downturn in recent years and exited the home theater market a while back. Because the company doesn’t make HT speakers at all anymore, it’s not possible for me to buy matching Atmos-enabled upfiring modules from the same brand. While I could just add new speakers or modules from a different company, I prefer not to mix-and-match speakers across separate brands, because I worry about timbre mismatching and don’t entirely trust EQ manipulation in the receiver to guarantee a consistent sound.
After thinking this over, I found that my best solution was to monitor Craiglist and eBay for used Soundworks speakers that could complement what I already have. Eventually, I acquired a set for a fairly reasonable price, which worked out nicely.
That wasn’t quite the end of the hassles, though. I agonized over speaker placement for a long time. Because my room was only wired for 7.1 when I built the home theater, and because my Surround and Surround Back speakers were already mounted in place and unmovable, I had to work around my former layout when planning the new one. This resulted in some compromises.
The height channels in an Atmos system offer the following options for placement:
- Front Height – High on the wall directly above the main left and right front speakers.
- Top Front – Mounted to the ceiling forward of the main speakers, between the front soundstage and the listening position.
- Top Middle – Ceiling mounted slightly in front of the listening position.
- Top Rear – Ceiling mounted behind the listening position, between the seats and the Surround Back speakers.
- Rear Height – High on the wall directly above the Surround Back speakers.
Further, when configuring for four heights, my new Denon receiver prohibits the two pairs from being directly adjacent to one another. They must be staggered with spacing between them. Therefore, you cannot install Front Height and Top Front simultaneously, or Top Middle and Top rear. There must always be an unused position or more between each pair.
As I mentioned earlier, Atmos is designed to have a base layer of 5.1 or 7.1 speakers at ground level and additional channels above. This proved problematic for me, because my Left and Right Surround speakers had been mounted high on the side walls, and my Surround Back speakers are on the ceiling.
When I brought in my electrician, we determined that it would be fairly easy to snake new speaker wire behind the front and left side wall of the home theater, but very difficult (and expensive) to run any above the ceiling. This effectively ruled out mounting new speakers to the ceiling unless I wanted visible wiring across it, which I certainly didn’t.
Ultimately, I came to the conclusion that my best option was to configure the height channels as Front Height and Top Middle.
I mounted the Front Height channels high on the left side wall and the support beam soffit on the right.
Next, I rewired my former Left and Right Surround speakers, which were already up near the ceiling, to become the new Top Middle channels. I then added new speakers on stands below them at ear level, which will be the new main Surrounds. My Surround Back speakers will remain where they were, on the ceiling.
This is not ideal for a few reasons. The Surround Back speakers should be at ground level, not up high. I suppose I could have reconfigured those speakers to be Top Rear or Rear Height channels, which would leave me with a 5.1 base and no Surround Backs, but I didn’t want to give up the Surround Backs. Also, the receiver is not capable of doing six height channels. Since the high speakers to the sides of the seats were already fixed to those positions, this would have forced me to use Top Middle and Rear Height, leaving me without any height channels in the front of the room. That seemed like a bad idea. The way it is now, the Surround Backs are far enough away from the seats that I expect the height level won’t really be too critical for those channels.
More concerning is the fact that the Surrounds and Top Middle speakers are too close together without enough separation, and the Top Middles really should be on the ceiling. I fear that this may leave me with a gap in the soundstage above the seats, but I’ll need to do a lot of testing to see if that’s really a problem.
Life is a game of many compromises, and this was the best compromise I could come up with given the limitations I faced.
What’s interesting is that this speaker layout is actually quite close to being in line with recommendations for the competing Auro-3D sound format. Denon offers an Auro firmware upgrade for the X5200W receiver that I may check out in the future. (There is a fee for that update, unfortunately.)
Wiring It Together
The two speakers that are currently my Top Middles on the left and right were previously wired before the walls or ceiling in the room were built. For the new equipment, my electrician was able to run speaker wire behind the walls in the front and to the left of the room, so the speakers on that side came out very neatly.
We were not able to get any wire through the support beam soffit on the right, however. For that side, I had to sneak some wire up the back of one support pole near the receiver, run it on the other side of the soffit, and then drop it down behind another support pole. Fortunately, this is mostly hidden out of sight and shouldn’t draw attention to the wires.
Here’s a peek at the jungle of wiring behind my equipment rack, also hidden from view.
With the physical labor out of the way, I spent a lot of time last night programming the receiver and running an Audyssey MultEQ XT32 calibration. I was then able to play some Dolby trailers from a demonstration disc provided by Dolby Labs to confirm that everything is working and sounds are coming from where they’re supposed to. Initial results sounded very good, but it got to be very late and I haven’t done much critical listening yet. Beyond the test disc, I also have the Atmos Blu-ray for ‘Transformers: Age of Extinction’. I look forward to watching that, as well as testing out the Dolby Surround upmixing of standard Blu-ray 5.1 and 7.1 soundtracks. I’ve been told that the receiver does a very good job with that.
This should be the fun part. More to come!