Digital audio - odd center channel/no voice

[imported_Septimus]

Hi,

This is an Audigy 4 Pro with Logitech 5450 5.1 surround speakers (rear 2 are wireless) under Win XP.

Analog audio works fine. Digital audio used to work fine, but a few weeks ago, I noticed odd behavior whenever I was on digital (optical) input. In a film, I'd hear all the sound and music but the speech would be very, very low. In a game, all the 'surround' stuff would sound fine, but the actual things the character was doing (say, firing a gun in Call of Duty 2) would be highly muted. The center speaker has plenty coming out of it (they all do) but it seems to me something with the center channel somehow. I've never heard of this happening before.

Anybody recognize this behavior?

Thanks!

 

[YOyoYOhowsDAjello]

Are you passing AC3 / SPDIF to the speakers or are you passing PCM and having it apply PLII to it?

For games, stick with analog. The A4 can't encode surround to digital.

 

[imported_Septimus]

This is encroaching a little on my ignorance of this sort of thing, but in the Creative Audio Console, there's a choice to use built-in encoding or use passthrough to the speakers. I currently have it set to use built-in encoding.

I think both the speakers and the card are capable of it - what's the difference?

I don't mind so much for games where I prefer using analog anyway, but for movies, it's a little odd.

 

[DaveSimmons]

Most games can't send surround sound over a digital connection with a Creative card. Only cards with Dolby Digital Live can do that.

Switch back to using an analog connection and be happy.

 

[imported_Septimus]

I'm okay with not having digital on games - my question, though, is why the change? When I first got the card, I got a fine digital signal in games. Analog sounded better (to me) so I used that.I listened to movies all the time in digital.

Now when I use digital for anything, it's like part of the sound is missing.

 

[DaveSimmons]

A few games have their own software encoder for dolby digital, you might have played one of those, or you might have had the game set to 2-channel stereo.

Also, you might have changed from passthrough to built-in encoding at some point.

 

[DaveSimmons]

( DP - mouse is extra clicky today )

 

[YOyoYOhowsDAjello]

Something that might have happened is you changed speaker settings in your game from stereo to 5.1
That might have screwed things up.

If your game was set to stereo before, then it would have sent all info as stereo and your card would have no problem outputting a pcm stream with that info. Then your speakers might have used PLII to send it to all speakers and it would have been decent.

If you set your game to 5.1, that might have screwed things up where the "center" and "surround" info would have gotten lost leaving you with the L/R signal to be played on 5.1 speakers (With PLII). You would have been left without the center info and just a hint of the center sound with whatever spilled over onto the L/R channels.

Just a guess.

Short version: Use analog for everything and don't worry about it. It's not like the decoder / DACs in your z-5450s are worth the trouble over what your A4 can do.

Also I guess I just don't understand why someone would get the z-5450s vs the z-5500s considering it's basically a $125 z-5300 set with "wireless" speakers and digital inputs. I don't see why someone wouldn't want to just run some small speaker wires to the surrounds vs. plugging two speakers into outlets. But whatever

 

[imported_Septimus]

I live in an apartment in Manhattan and it was worth it for the wireless-ness of it. Otherwise you're absolutely right, I would have gone for the 5500.

I'm curious, though, when you say 'the trouble over what your A4 can do' -- are you saying that the A4 is poorly matched with these speakers because it's capable of much more, or that the A4 sucks?

All my audio knowledge is in the land of synth, I don't know too much about this stuff. When and why would you use a built-in (en/de)coder versus passthrough?

 

[PurdueRy]

Originally posted by: Septimus
I live in an apartment in Manhattan and it was worth it for the wireless-ness of it. Otherwise you're absolutely right, I would have gone for the 5500.

I'm curious, though, when you say 'the trouble over what your A4 can do' -- are you saying that the A4 is poorly matched with these speakers because it's capable of much more, or that the A4 sucks?

All my audio knowledge is in the land of synth, I don't know too much about this stuff. When and why would you use a built-in (en/de)coder versus passthrough?

if you enable passthrough and/or use digital you will be using the DAC's in your speaker "receiver". If you allow decoding to be done in your hardware and use analog connection you will use your A4's DACs which will be much higher quality resulting in higher fidelity sound.

 

[imported_Septimus]

Aaaah, okay. I had no idea about any of these. I guess I shouldn't be trusted to make audio hardware purchases.

Thanks for the help!

 

[Auric]

YOyoYOhowsDAjello prolly hit on it with the speaker setting. 2.1 would be correct if using 2ch PCM output without affecting the ability to stream pre-encoded surround. Setting to more channels would cause sounds to drop out. Games do not universally offer configuration though in which case it would depend upon the Audio Console setting.

As said, all this can be rendered irrelevant and you can prolly enjoy better sound quality and effects by just using analog output in which case the AC can be set to 5.1 or whatever is appropriate for the PC speaker kit.