How to stream video with Dolby 5.1 surround sound

So you’d like to have Dolby 5.1 “surround sound” in your home theater.  The first step is, of course, to purchase a “surround sound” kit.  This will include six speakers — a subwoofer, a center speaker, and four small speakers to be placed in four corners of the room.  This will also include a six-channel audio amplifier.  Housed with the audio amplifier will be a decoder that can detect and receive a Dolby 5.1 surround sound signal, and that decodes it into six audio signals to be fed into the six audio amplifiers.  (You might find that your surround-sound amplifier is so old that it does not know how to decode a Dolby 5.1 signal, in which case you will have to replace your amplifier with a newer model.)

The next challenge is to find something to watch that has a Dolby 5.1 signal.  By far the easiest way is to purchase a DVD or Blu-Ray player that can read the Dolby 5.1 audio track on a disk and can pass the Dolby 5.1 signal to the decoder mentioned above.

There are two ways that you might connect your disk player to your surround sound amplifier for purposes of Dolby 5.1 surround sound.  One way is a shielded audio cable with an RCA plug at both ends.  The other way is a so-called “SPDIF” optical cable.  (If you get stuck with a disk player with an optical output and an amplifier with an RCA input, or vice versa, there are adapters you can purchase that will convert from one kind of connection to the other.)

Related to this is that you need to find a disk to play that has a Dolby 5.1 audio track.  Most recently released movies on DVD and Blu-Ray do have a Dolby 5.1 audio track.

When you cobble all of these things together, how do you know that you succeeded?  One indication that you have succeeded is that the amplifier will probably have a light or screen legend that will appear whenever the amplifier detects that the incoming audio signal is a Dolby 5.1 signal.  It is important to learn where this light or screen legend is, as I will mention below.  A second indication that you have succeeded might be that as you watch a movie, you hear non-identical things being emitted from the various room-corner speakers.

You might think that you could buy a “test DVD” that you could put into your DVD player to test this.  The test DVD would run through each of your six speakers one by one, with a voice saying (for example) “left front” that is emitted by the left front speaker.  Indeed you might think that the company that sold you your surround sound system would provide such a disk.  But I haven’t been able to find such a test DVD.

Once you get to the point where you can consistently get surround sound to work for watching movies on disk, and once you learn to interpret the lights or screen displays on your amplifier so that you know you are actually getting Dolby 5.1 to work, can you sit back and relax?  Of course not.  If there’s anything we have learned it is that physical media are on their way out.  Some day we won’t use disks any more and we will usually stream our entertainment.

Which then raises the natural question, how may we set up our streamed entertainment so that we can somehow get a Dolby 5.1 signal and feed it to our surround sound amplifier and get six-channel surround sound from our streaming service?  And that is the point of this blog article.

First let’s talk about how we do our streamed entertainment.  There are quite a few ways to do it.

You might have a “smart television” which is a television on which you can install apps that permit you to stream various things.  A typical smart television will have a Netflix app and a Hulu app, for example.  The television connects to your Internet (maybe by wired ethernet, which is the best way, or by wifi, which is not as good as wired ethernet) and when you run your Netflix app, it connects to the Internet and streams some program from a Netflix server to your screen.  Some smart televisions are able to extract a Dolby 5.1 signal from the streamed program (if indeed the streamed program has a Dolby 5.1 signal in it) and can pass this signal to your surround-sound system.

Probably your DVD or Blu-Ray player has apps like Netflix and Hulu.  The player connects to your Internet (again wired ethernet is the best way to do this) and when you run your Hulu app, it connects to the Internet and streams some program from a Hulu server to your screen, by means of an HDMI cable.  Then if you have about five layers of good luck, you will be able to get surround sound.  For this to work, the streaming service provider has to include a Dolby 5.1 signal in the streamed program.  Then the app has to know how to pick up the Dolby 5.1 signal and pass it to the disk player hardware.  The disk player hardware has to be able to pass the Dolby 5.1 signal to the digital audio output of the disk player.  (As mentioned above this might be an RCA jack or it might be an SPDIF optical jack.) You need to have installed a cable that connects this digital audio output of the disk player to a digital audio input of your surround sound amplifier.

A problem with the smart-TV streaming approach, or the disk player streaming approach, is that likely as not you will be unable to load all of the apps that you want to load.  For example you might find that you cannot install the HBO Now app on your TV or disk player.

So the usual best practice these days for streaming is to use a streaming media stick or streaming media box.  For example you might use an Amazon Fire TV Stick or a Roku Stick.  An advantage to this is that every new app that you might care about (for example HBO Now) is available for installation on Fire TV Sticks and boxes and is available for installation on Roku sticks and boxes.

The streaming media stick has exactly one output, namely an HDMI output.  This HDMI output provides video and an audio signal to the television, all through the HDMI connector on the television.  You might then get lucky and find that you can stream a Dolby 5.1 signal through the stick to the television and from there to the surround sound amplifier.  For this to work, many things have to go right.  The streaming service provider has to include a Dolby 5.1 signal in its streamed program.  The app on the stick has to know how to pass the Dolby 5.1 signal along to the hardware of the stick.  The stick has to know how to pass the Dolby 5.1 signal into the HDMI port.  The television has to know how to extract the Dolby 5.1 signal from the HDMI port and pass it to the digital audio output of the television.  And then you need to have connected a digital audio cable from the television to the surround sound amplifier.  (Again this might be an optical cable or an electrical cable with RCA plugs.)

The main catch here is that likely as not, your television does not know how to extract the Dolby 5.1 signal from the incoming HDMI stream.  Thus it is unable to pass the Dolby 5.1 signal along to the surround sound amplifier.

You might think that what you will need to do, to successfully get surround sound working with your streaming media stick, is to junk your existing television and buy a super-expensive new television that knows how to extract the Dolby 5.1 signal from the HDMI stream from the media stick.  I am delighted to tell you that you will not have to do this.  All you need to do is spend $28 to buy a Dolby 5.1 extractor (see it here on Amazon).  You plug your streaming media stick into this box.  You run an HDMI cable from this box to your television.  And (this is the important part) this box has a digital audio output.  So you run a digital audio cable (in this case, an optical cable) from this box to an input on your surround sound amplifier.  This box extracts the Dolby 5.1 signal from the HDMI stream, and passes it to the digital audio output.

What are all of the things that have to go right for you to enjoy Dolby 5.1 surround sound with a streamed program or movie on your streaming media stick?  Lots of things have to go right.

First, the streaming service provider has to include a Dolby 5.1 signal in its streamed signal.  HBO Now includes Dolby 5.1 in some of its programs and not others.  I learned through trial and error that HBO Now includes a Dolby 5.1 signal in Game of Thrones for example but does not include a Dolby 5.1 signal in most of its on-demand television programs.  At present, in contrast, Hulu does not provide a Dolby 5.1 signal for any of its programs.

Second, the app has to pass the Dolby 5.1 signal along to the stick hardware.  The stick hardware has to pass the Dolby 5.1 signal along to the HDMI output of the stick.  The above-mentioned extractor box then extracts the Dolby 5.1 signal and passes it to your surround-sound amplifier.

What I found, through trial and error, is that for example I can watch Game of Thrones on a Roku stick and use the extractor, and I will actually get Dolby 5.1 surround sound.  This works quite well with the Battle of the Bastards episode that aired a few days ago.

Oddly, the exact same setup using a Fire TV stick does not permit me to watch Game of Thrones and get Dolby 5.1 surround sound.

As I mentioned above it is crucially important to know how to interpret the blinky lights or display of your surround sound amplifier so that you will be able to check for yourself that (for example) the Game of Thrones surround sound works on a Roku stick but does not work on a Fire TV stick.

Why does it not work on the Fire TV stick?  It could be either of two things — the HBO Now app for the Fire TV stick might be stupider than the HBO Now app for the Roku stick, so far as Dolby 5.1 is concerned.  Or it could be that the Fire TV stick is stupider than the Roku stick, so far as Dolby 5.1 is concerned.