Today the biggest buzz in the world of home theater audio is “object oriented” audio like Dolby Atmos, DTS:X, Auro3D and probably some more that I’m forgetting. This is new to most consumers but it isn’t groundbreaking technology. The underlying mathematics have been well understood since the 1870s. The first products that used this kind of technology were phased-array radars in World War II. However, only now is is coming to your living room. The big developments that have led to these technologies entering the consumer market are: improved compression algorithms which allow dozens of streams to exist on a single disc at once and cheap but powerful chips which can compute the required amplitudes and phase delays in real time. That being said, I still think it’s pretty cool. The academic term behind this is “wave field synthesis”.
What these various coding and processing schemes promise is to allow your receiver to dynamically do wave field synthesis in your living room. Your receiver will take all of the speakers in your room and all of the sources on your BluRay and do its best to recreate the sound field the sound engineer intended. Previously, this was done by the engineers at the recording company and saved in various stereo and surround formats like Dolby Digital.
This is cool, of course, but the question is: is it helpful and worth the expense? For a 5 or 7 channel surround sound setup, I would be inclined to see this as an improvement if your receiver let you specify the angles and heights of all of your speakers. The receiver would then create a custom mix that used the appropriate amount of each speaker, tailored specifically for your setup. We already have distance, why not angle as well? At this time, I have not seen any receiver with this feature.
Instead the industry has decided to try and sell more speakers and make another push at getting people to install height speakers. This is where I worry about the technology. For those of us with pretty good speakers already, the prospect of adding four more overhead speakers means a significant investment. Not just in buying good ceiling speakers, which cost more than regular speakers of similar quality, but installing and wiring them as well. Also, you probably will need a new receiver which has to further cut costs on the amplifiers in order to add support for more channels. It’s really not something that entices an enthusiast like myself. Height speakers have been tried before and did not find a place in our systems when there were only two to consider. With four, it seems to not be worth the trouble.
One solution being offered by Dolby is instead of having to buy and install ceiling speakers is to have manufacturers sell modules what clamp on top of existing speakers to bounce sound off the ceiling. Anyone who knows how speakers work knows this is a recipe for interference problems. If both the Atmos module and the main speaker are playing at the same time, they will interfere. I guess they are banking on only using the Atmos modules rarely and not in conjunction with others. This, of course, undermines the selling point. Why would you want to buy something that you don’t use much but cuts out your best speakers when you do? [EDIT: 8/16/2015] I had a chance to ask a speaker designer about this here. I think it addresses some of these points really well, especially if the signal is limited to only be above 1.3Khz.
While extra speakers seem like a non-starter to an enthusiast like myself, I really don’t see a market for them amongst the layman consumer of surround sound. That market is moving towards soundbars and other convenient and compact systems. Who wants to put 11 small speakers throughout their living room? Five is still the limit for most casual surround sound consumers.
Overall, I’m feeling bearish about this new technology. I don’t see it catching on in the mass market. I think the potential benefits for enthusiasts are overlooked, while the wrong parts are emphasized. I think these new codecs will ultimately go the way of 3DTVs. They will become standard on all receivers and left unused by enthusiasts and the mass market alike.