Dolby Pro Logic II and Surround Sound Headphones

[Luminoth Prime]

So I own a Logitech G933 7.1 Surround Sound headset, and was wondering how best to use it with the Dolby Pro Logic II decoder. From my understanding, the decoder isn't true 5.1, but rather more of a digital 5.1 that's stereo, but sounds like surround. Which I think is exactly what my 7.1 headset does when the surround sound is turned on, so would it be best to turn the decoder on (for supported games) and turn off my headset's surround sound? Otherwise it seems like it's a stereo signal mixed like 5.1, which then goes through my headset and is mixed to sound like 7.1. I imagine that extra step just causes more problems and messes up both effects.

[Franpa]

It's a stereo signal containing additional information that a decoder can utilize to split the audio in a fancy way to achieve independent audio out of more than 2 speakers. It's not as effective as outputting each speaker signal on its own wire though (I forget the technical reasons why Dolby Digital is inferior to discrete 5.1 audio).

Wouldn't turning off the surround mode make your headphones output stereo audio? Or is the surround mode a "enhancement" specifically for upmixing low channel audio and isn't required if surround sound audio is outputted to them?

[mstreurman]

(08-15-2017, 02:02 PM)Luminoth Prime Wrote: So I own a Logitech G933 7.1 Surround Sound headset, and was wondering how best to use it with the Dolby Pro Logic II decoder. From my understanding, the decoder isn't true 5.1, but rather more of a digital 5.1 that's stereo, but sounds like surround. Which I think is exactly what my 7.1 headset does when the surround sound is turned on, so would it be best to turn the decoder on (for supported games) and turn off my headset's surround sound? Otherwise it seems like it's a stereo signal mixed like 5.1, which then goes through my headset and is mixed to sound like 7.1. I imagine that extra step just causes more problems and messes up both effects.

Your headphones use virtual or software surround, which means that you only have 2 speakers (drivers) in your headset as opposed to 8 for real 7.1 (actually 9 because the subwooferchannel will need a driver on both ears).

So outputting DPL2 wouldn't do anything since it splits up stereo sound though a matrix into 4 seperate speakers thanks to an extra (inaudible) signal in the output-sound. Worst case scenario it would make it sound much worse because if the decoder expects the extra speakers to output sound to but they arent there, you would not get the sound that would be coming from the rear speakers.

[Franpa]

Did you look up the specs on his headphones? I think it's been possible for a while now to get headphones with multiple physical speakers on each side of the headphones. They're usually $300+ AUD. Maybe I misunderstood the technology and it IS just software surround.

[skid]

I looked up the specs and the G933 has two physical drivers.  The 7.1 enhancement is simulated surround.  This means that the Dolphin's Dolby Pro Logic II decoder should be disabled for this headset.

[mstreurman]

I did too, so... yeah...

[Luminoth Prime]

(08-18-2017, 09:34 PM)mstreurman Wrote: Your headphones use virtual or software surround, which means that you only have 2 speakers (drivers) in your headset as opposed to 8 for real 7.1 (actually 9 because the subwooferchannel will need a driver on both ears).

So outputting DPL2 wouldn't do anything since it splits up stereo sound though a matrix into 4 seperate speakers thanks to an extra (inaudible) signal in the output-sound. Worst case scenario it would make it sound much worse because if the decoder expects the extra speakers to output sound to but they arent there, you would not get the sound that would be coming from the rear speakers.

(08-19-2017, 08:13 AM)skid Wrote: I looked up the specs and the G933 has two physical drivers.  The 7.1 enhancement is simulated surround.  This means that the Dolphin's Dolby Pro Logic II decoder should be disabled for this headset.

All right, then I'll just disable both DPL2 and the headset surround sound. The latter only makes sense in games that support surround sound, such as Titanfall 2, which recognizes my headset as 7.1, so it outputs audio accordingly. I was just wondering if the same logic applied here, and that by enabling DPL2 I might be able to take advantage of my headset's surround sound.

Thanks for the help!

[Franpa]

I configure my soundcard to 7.1 channel mode and disable all the channels except the Front Speakers, forcing it to downmix the audio in to stereo. Then I can use whatever sound mode sounds best in each game with my stereo headphones. This setup is great for programs that stubbornly output in a surround sound mode, like Dragon's Dogma and Dark Souls. Some games may have extra audio when utilizing a surround sound mode or different audio mixing that can sound significantly different to the stereo mix.