I made a post in the inFamous thread about how I was getting a deadzone in the back of my 5.1 setup even with all of the ingame and system settings set properly.
The problem is fairly easy to identify in an open world game like inFamous. The best way to tell is in segments where you have an NPC in the area with you talking to you. If you spin your camera around, you'll notice that the voice practically disappears as the source pans directly behind you, and reappears on the other side when you get there.
The solution proposed was to switch over to DTS, which has effectively solved the problem. However, I'm not one for just sweeping problems under the rug, so a friend and I ran some tests.
The problem pops up in MGSV Ground Zeroes as well. Stand with a flagpole behind your camera and move the camera around in LPCM mode. Set it to DTS and try again. It's a world of difference.
The results seem to vary depending on the game. AC4 Black Flag, for example, works just fine. I even had an NPC conveniently start to whistle for me to help me with my test. On the other hand, my friend reports that the problem is present in NFS Rivals; you don't hear the honking directly behind you in LPCM.
The best guess that I can come up with is that, in LPCM mode, the PS4 is not discerning between 7.1 and 5.1, and will output 7.1 as long as the game supports it, no matter what it's plugged into. As a result, if you have a 5.1 setup, it sounds as if you're missing two speakers behind you. With games that only support up to 5.1, it works just fine. I'm not an expert and I don't really know how these things work, so this is just a hypothesis at best. However, there definitely seems to be an issue with the output of 5.1 via LPCM for many games on the PS4.
If you have your PS4 plugged into a 5.1 setup and are running with LPCM, please try it out and report back if you have the same issues. It's a very specific problem that's hard to notice since it's so conditional based off of your setup and settings, so there hasn't been very much noise made (no pun intended) about the situation, but hopefully, assuming there really is a problem, we can raise some awareness and get Sony to do something about it.
Update for more specificity on the issue:
The problem is fairly easy to identify in an open world game like inFamous. The best way to tell is in segments where you have an NPC in the area with you talking to you. If you spin your camera around, you'll notice that the voice practically disappears as the source pans directly behind you, and reappears on the other side when you get there.
The solution proposed was to switch over to DTS, which has effectively solved the problem. However, I'm not one for just sweeping problems under the rug, so a friend and I ran some tests.
The problem pops up in MGSV Ground Zeroes as well. Stand with a flagpole behind your camera and move the camera around in LPCM mode. Set it to DTS and try again. It's a world of difference.
The results seem to vary depending on the game. AC4 Black Flag, for example, works just fine. I even had an NPC conveniently start to whistle for me to help me with my test. On the other hand, my friend reports that the problem is present in NFS Rivals; you don't hear the honking directly behind you in LPCM.
The best guess that I can come up with is that, in LPCM mode, the PS4 is not discerning between 7.1 and 5.1, and will output 7.1 as long as the game supports it, no matter what it's plugged into. As a result, if you have a 5.1 setup, it sounds as if you're missing two speakers behind you. With games that only support up to 5.1, it works just fine. I'm not an expert and I don't really know how these things work, so this is just a hypothesis at best. However, there definitely seems to be an issue with the output of 5.1 via LPCM for many games on the PS4.
If you have your PS4 plugged into a 5.1 setup and are running with LPCM, please try it out and report back if you have the same issues. It's a very specific problem that's hard to notice since it's so conditional based off of your setup and settings, so there hasn't been very much noise made (no pun intended) about the situation, but hopefully, assuming there really is a problem, we can raise some awareness and get Sony to do something about it.
Update for more specificity on the issue:
I can't imagine it being intentional. To me it seems like a major oversight in terms of the PS4-side down mixing, or lack thereof. Here are the projected scenarios:
Receiver supports 7.1, 7.1 speakers attached -> PS4 sends 7.1 signal, No problems
Receiver supports 7.1, 5.1 speakers attached -> PS4 sends 7.1 signal, receiver down mixes to 5.1. No problems
Receiver does not support 7.1 but accepts 7.1 input -> PS4 sends 7.1 signal, receiver down mixes to 5.1. No problems
Receiver does not support 7.1 and does not accept 7.1 input -> PS4 cuts off last 2 channels rather than down mixing properly, sends 5.1 signal with missing channels. Problems.