Have I got this setup right?

cjard

Active Member
I have a laptop that promotes itself as having "HD audio" (caveats to the HD audio sticky I've read) it DOES have an optical digital out..

So I bought a cable that was 3.5mm jack on one end and toslink on the other, suitable for connecting to my Denon AVR2809


I connected it all up, switched the amp to the relevant input and then had the choice of Dolby PLII, DTS NEO6 or the DSP surrpound modes.. Playing a youtube clip just to test the audio worked I noticed some really nasty high frequency distortions/bursts of noise that arent there when using a normal analog link..

Edit: At this point I think something is a little wrong, because the amp display shows: Digital Connection, FL, FR - does it mean the amp has detected only a stereo source coming over the optical cable? This means it's some combination of VLC, dvd player or laptop hardware that isnt transmitting the full 5.1 sound to the amp? Is it something that is configured in software?


Switching to foobar and playing an mp3 was a better result, so I then loaded a movie (V for Vendetta) because it said it had 5.1 sound on, and played it using VLC media player..

In the movie, having made sure I chose the audio device as "5.1 surround" the audio track menu was greyed out so i guess VLC knew to just use the only 5.1 that was on the disc..


So, I'm listening to this movie in NEO6 mode and I'm painfully aware that all the speech is coming through the centre speaker, and the sourround and front left/right are pretty much playing the background music only.. There were a few explosions but completely lacking any bass (the subwoofer self-switch-on circuit wouldnt activate due to low signal level) and in only one point did I really hear a car drive from left to right across the soundstage, so I was left thinking.. "Well this is a bit.. crap"

Now, is it just a badly made disc? Does the quality of soundstage I get really ultimately depend on how the audio channels have been mastered and assembled? SHould I have tried another disc (i was short on time) ?
Have I screwed the setup up in some way? I'm using a toshiba stellite pro laptop, fairly modern thing so I'd hope it's not a hardware issue of the laptop. Is VLC doing its job correctly? Is there some magic I havent performed in relation to setting up the optical link (i.e. something beyond "plug in, choose optical in windows, set optical on amp") as regards audio stream formats, or does the amp work all that out?

I also had to turn the amp really far up to get an appreciable volume.. Setting it to 0db when playing stereo analog audio into the CD phono connector on the amp leaves me unable to *think*, it's that loud... The same computer plays the DVDs, and all the necessary and relevant volumes are turned up so i dont think it's a "quiet source because of incorrect volume settings" issue (though I know DVD audio is quite quiet as standard)

I guess I was just hoping to be slightly more wowed with explosions and things coming from left and right.. rather than hearing what I thought was a lot of hiss in the sound of the movie, where it sounded like everyone was speaking directly in front of me.. (because it was turned up far.. I note that the fluorescent display of the amp makes quite an audible buzz if there is no music playing, so I set that to display off after a few seconds)

Thanks in advance for anything I should check or other movies you can recommend that might be a more wowing experience.. I'll have to also investigate why the sub doesnt turn on; when I previously had the sub running on the line out of a stereo amp, with each of the amp and sub's volumes fixed to a good level (then controlling volume from the source) I had a serious and appreciable amount of bass.. Now that I've run through audyssey on the Denon, it's left my sub at -4db (when all other channels are +2 to +4) and everything sounds very bassless.. (I know that the sub's volume control has a bearing on what audyssey works out, but audyssey to me left me with an EQ curve that was way overly full on the midrange and songs sounded awful; the Flat setting on audyssey eq was much nicer)
 
Last edited:

StevieBuck

Well-known Member
Sounds as if you are just getting a stereo signal from the laptop. The sound modes (Dolby Pro Logic, DTS Neo, etc) can up-mix stereo signals to 5.1 giving you a surround sound effect. This won't be as good as listening to the actual 5.1 soundtrack on the DVD.

Could you confirm whether that is the case or not? The receiver display should show the current input format. If you are only getting stereo audio it will show something like 2 channel PCM 48kHz.

I take it you needed the 3.5mm adaptor for the optical output on the laptop?
 

Dean

Well-known Member
Most laptops have a combined analogue/digital output, using a single 3.5mm socket. This will supply a stereo analogue output or it can also output a digital signal by using a suitable lead. Most modern laptops will use optical . Try to confirm that the laptop is actually outputting optical, look for the red light in the socket.

As well as enabling the optical output on the soundcard, you'll probably have to check and confirm any settings on your DVD player software as well.
 
Last edited:

cjard

Active Member
mmmm.. If I go into properties of the SPDIF Audio Device in vista, I have a box that says "Choose what your receiver supports" and I have:

DTA audio
Dolby Digital

both ticked. If I choose either and press the TEST button I hear tinkling noises from all 5 speakers in turn, and 5 lights come on on the receiver. Then it goes back to stereo when windows plays a bong noise..

VLC media player is set to 5.1, but the receiver just still displays 2 channel lights... So something is screwy with the 5.1 audio out of VLC? The other tests imply the hardware can do 5.1 down the single optical cable?
 
mmmm.. If I go into properties of the SPDIF Audio Device in vista, I have a box that says "Choose what your receiver supports" and I have:

DTA audio
Dolby Digital

both ticked. If I choose either and press the TEST button I hear tinkling noises from all 5 speakers in turn, and 5 lights come on on the receiver. Then it goes back to stereo when windows plays a bong noise..

VLC media player is set to 5.1, but the receiver just still displays 2 channel lights... So something is screwy with the 5.1 audio out of VLC? The other tests imply the hardware can do 5.1 down the single optical cable?

Is it possible the "Bong" and the media you are playing are only stereo?
 

cjard

Active Member
Ummm.. The bong probably is only stereo.. very confused why VLC would show 5.1, and let me enable it (alongside other options for 2+2 stereo or normal sereo) but then it renders as 2ch instead of 5.1ch.. The disc definitely has 5.1 audio on, I've checked with DVDShrink. Right now it feels like VLC or the laptop isnt rendering it.. But when windows does its 5.1 checks, it IS rendering it..

So.. the audio iff the DVD, is it a passthrough the sound card circuitry vs the test that windows does being generated by the sound card.. Not sure
 

The latest video from AVForums

AVForums Movies Podcast: Streaming Theatrical Releases And The Future Of Cinema
Subscribe to our YouTube channel
Support AVForums with Patreon

Top Bottom