7.1 vs 7.2 Surround Sound
Having a surround sound system gives you the best aural experience with your movies or video games. There are a number of surround sound specifications, but at the very top of the list are 7.1 and 7.2 systems. The main difference between 7.1 and 7.2 surround systems is that the latter has an additional sub that should give more oomph to the sound. But you should not be fooled. A true 7.2 systems should have two separate channels for the subs, so that the two subs may not be outputting the same signal. Some 7.1 systems may seem like 7.2 systems because they have two subs. But the truth is, the two subs get the same signal from a single channel via a Y splitter. This is not true 7.2, although it might seem so at first glance.
Having two separate sub channels should give you directionality when it comes to the low frequency sounds. This can be achieved by altering volume levels of the individual subs so that it seems like it is coming from a certain spot and not dead center. If you used a 7.1 system with a splutter for two subs, the sound would always seem dead center since the two will always have the same intensity and volume.
The main drawback for 7.2 systems, and even 7.1 systems, is that there is very little support for them in modern media. These systems are not that common place and supporting them does not give much return to media makers. Currently, most DVD systems only support 5.1 systems while others can extrapolate up to 7.1. You only get 7.1 sound on Blu-ray hardware, and the content needs to be meant for 7.1 systems. 7.2 systems are even worse off since virtually no media does 7.2. Using it with modern systems, mean that you would still get 7.1 sound since there is no other resort other than replicating the same sound in both subs; pretty much just like using a Y splitter on a single sub channel.
Summary:
- A 7.2 system has an additional sub that is not available on the 7.1
- A 7.2 system should give you better directionality when it comes to low frequency sounds
- Few systems support 7.1 while even fewer support 7.2