5.1 Surround Sound
What exactly is surround sound? What do the numbers in 5.1 stand for? What's the difference between Dolby Digital and DTS? Now that I have all these speakers, how do I properly set up 5.1 surround sound?
This section will help explain the differences from stereo sound to 5.1 surround sound. VXP will further explain the differences between the two major 5.1 decoders on the market which are Dolby Digital surround sound and DTS. VXP is here to educate our customers why 5.1 surround sound can enhance your outdoor movie experience. To better understand 5.1 surround sound VXP will first discuss stereo sound.
What is a stereo sound?
Stereo sound is basically like natural human hearing. There is right side and a left side of the sound spectrum. The idea of stereo sound is to create atmosphere where the sounds of the actions that you see are congruent of with what you hear on your right and left side. For instance you see a ambulance on the screen traveling from the right to the left of the screen. You would hear the sound of the ambulance through a stereo sound system start from the right speaker and eventually grow lounder in left speaker as the ambulance travels in that direction.
Basic Stereo Sound System
How is this possible? Audio can be sepearted onto different audio tracks. A stereo sound sytem in its simplest form has a right audio track and a left audio track. It's like taking two microphones and setting them on oposite sides of the same room at a party. You record the different conversations in the room. The recording would pickup different dialogues from the right mic than the left mic. During playback of that recording you would hear the different converstaions coming from the right and others from the left. If there was only one mic in the room you would here everything at once but no separation. This would be a one track recording or "mono" audio track. So two audio tracks is the magic number to make it stereo.
You are not limited to just two speakers in a stereo setup. For larger audiences, more sound reinforcement is required. That is why for larger movie screen systems more speakers are set up to distribute the sound to the entire audience. After setting up your first two speakers on the right and left side. Additional speakers can easliy be linked together like the photo below.
Stereo Sound System For Larger Audience
What is 5.1 surround sound?
The concept of surround sound is "surrounding" the audience with multi channel audio. Sound is essentially reaching the audience from all directions like a audio hologram. Every speaker in a basic 5.1 setup has its own audio track. It differs from a stereo setup because a stereo setup is two separate outputs for its audio track and 5.1 surround sound is six separate outputs for its audio track.
Basic 5.1 Surround Sound System
Lets define the meaning of the numbers in "5.1". The "5" represents five speakers. These speakers are the right front, center, left front, right rear, and left rear. The ".1" is the subwoofer. So it's a minimum of six speakers in a 5.1 surround sound setup. Each of these speakers has a separate audio track. The two major competing compaines that VXP's 5.1 Decoder Workstation work with is Dobly Labortories and DTS or "Digital Theater Systems."
Delivers 5 discrete audio channels and 1 LFE channel from a 6 channel source:
- Two channels for speakers at the front - left (L) and right (R).
- One channel for speaker at the center - center (C). Note: This speaker is where most of the dialogue comes from.
- Two channels for surround speakers at the rear - surround left (LS) and surround right (RS).
- One low-frequency effects channel (LFE). All of the very low bass in an audio track such as earthquakes, planes flying over, and car chases
- Describes the Dolby Digital, and Digital Theater Systems (DTS). Source media, usually DVD and sometimes Laser Disc or satellite/digital cable is often branded with "Dolby Digital" and/or DTS logos.
- DTS uses a higher sampling rate than Dolby Digital, thus DTS uses less compression and achieves higher fidelity than Dolby Digital.
- Surround Sound speaker placement: (6 speaker channels in total)
Setting Up 5.1 Surround Sound
For movie surround, the front speakers should be placed at the edges of the screen, toed in to face the central listening location, and the tweeters should be ear height. The center speaker should be placed at the center of the screen and as close to ear height as possible. Rear channel speakers should be placed high, slightly behind the listening position. The subwoofer can be placed anywhere betweem the front channel speakers.