How would a 7.1 Dac work?

[CarzyBear]

I'm curious how a 7.1 dac would work, like the Sound BlasterX G1 or the HyperX 7.1 dac. How does it make a 2.0 headset have surround sound? 

[Bombastinator]

28 minutes ago, CarzyBear said:

I'm curious how a 7.1 dac would work, like the Sound BlasterX G1 or the HyperX 7.1 dac. How does it make a 2.0 headset have surround sound? 

This got explained to me once.  I didn’t really follow it. It has to do with a bunch of tests that were done on simulated heads.  There are different profiles or something, but it’s about echos and pitch changes and stuff and how a sound directly behind you sounds subtly different than a sound directly in front of you because of various things I don’t understand.  Or something.  The impression I got is while a lot of people fit a single profile many don’t and you have to have the right profile to make it work or it doesn’t.   

[CarzyBear]

1 minute ago, Bombastinator said:

This got explained to me once.  I didn’t really follow it. It has to do with a bunch of tests that were done on simulated heads.  There are different profiles or something, but it’s about echos and pitch changes and stuff and how a sound directly behind you sounds subtly different than a sound directly in front of you because of various things I don’t understand.  Or something.  The impression I got is while a lot of people fit a single profile many don’t and you have to have the right profile to make it work or it doesn’t.   

Oh, so it's not actual surround sound, just makes it sound like it is. Cool. Thanks!

[Bombastinator]

Just now, CarzyBear said:

Oh, so it's not actual surround sound, just makes it sound like it is. Cool. Thanks!

It sort of is in that it can create the effect.  I think.  It’s useful apparently for things like shooter games where the location of a sound can make an immense difference.  But as I said I don’t really understand.

[Eigenvektor]

4 minutes ago, CarzyBear said:

Oh, so it's not actual surround sound, just makes it sound like it is. Cool. Thanks!

Exactly. You can hear surround sound despite only having two ears. One reason is the shape of your ears. It makes noise sound slightly different depending on where it is coming from.

The other is the distance of your ears. Sound arrives at each ear at a slightly different time, depending on where it is coming from.

 

This can be used for "virtual surround" by approximating these effects in software. The effect isn't perfect, since each person's ears are slightly different, so it works best if your ears are "average" in terms of shape.