[MadDogMike]

I have a Samsung HW-H750 sound bar. I recently tested it's 5.1 capabilities using the Disney WOW calibration Blu-ray disc. All channels worked fine, except there was no sound from the sub when it tested the LFE channel.

So now I'm trying to diagnose the problem. Does the problem lie with the sound bar, the Disney disc, the Blu-ray player, or something in between?

I have the Blu-ray player connected to the TV via HDMI, and the sound bar connected to the sound bar via HDMI ARC. HDMI ARC is supposed to pass 5.1, so I don't think the connection is the issue.

Now, the sub itself works fine, I can hear it when playing music and watching movies. However, perhaps it's possible that in those cases the sub is playing low frequencies from the left / right / center channels and not from the discrete ".1" LFE channel.

What's the easiest way to diagnose this, outside of buying a different 5.1 test disc?

 

[MadDogMike]

Incidentally, I found that, out of the box, my Blu-ray was set to downmix to stereo. I changed that to "Surround Compatible," but that didn't help. I also tried switching between PCM and Bitstream (Unprocessed), and that didn't help, either. In all cases, all channels work with the Disney test signal except the LFE. And yet I can clearly hear the sub on other content. Very strange.

 

[YOHA]

Did you try the calibration disc on other speakers? If yes, did the LFE channel work? If you didn't try it with other speakers, maybe you can try to play another bluray disc and see if the problem is still present.

For your bluray player, you should stick to bitstream since it is the soundbar's task to decode the audiostream.

 

[MadDogMike]

I haven't tried other speakers. (Wife made me get rid of my old "real" 5.1 system in favor of the soundbar, for aesthetics.)

There is some debate as to whether the TV will pass 5.1 from an external source via HDMI-ARC. Samsung tech rep says it will, but I can't confirm it in writing anywhere. So I may try hooking the Blu-ray player directly to the soundbar to see if the issue is in the HDMI-ARC pass-through.

Of course, the Blu-ray player's only audio output is coax, and the soundbar's only audio input is optical! Come on Samsung, get it together! Decide on one or the other and stick with it across all of your products! Yes I can get a coax-optical adapter, but I shouldn't have to. That's why I bought all of one brand's product line, because it should all work together!

As for trying another Blu-ray disc, it would almost have to be another test/calibration disc to determine if I'm really getting bass from the discrete LFE channel, versus the sub just playing bass from the L/C/R channels. I may try the direct-connect option first, and if that doesn't help try a different test/calibration disc.

As for selecting bitstream, with my hookup, I'm wondering if the soundbar really is decoding the audiostream or if the TV is and passing it through.

 

[YOHA]

Most TVs downmix a 5.1 signal, your samsung probably as well. What's the model number of your TV and bluray player?

I had a comparable problem with my laptop (which can only decode 2 channels DTS or DD) connected to the HW H750. Instead of passing the 5.1 signal to the soundbar, the laptop decoded it to 2 channels which negatively affected the SQ. The solution for me was to use a videoplayer that has a pass through option.

In order to test whether the soundbar received an untouched 5.1 signal (meaning the soundbar decodes the audiostream itself), I set the surround mode on the soundbar to AUTO. With this mode enabled, the soundbar turns on a fancy surround effect (which screws up the sound by the way) whenever it receives a 5.1 signal. If the soundbar has received a real 5.1 signal, surround mode ON should sound exactly the same as surround mode AUTO. If not, surround mode AUTO should sound the same as surround mode OFF.
Try this in order to determine whether the TV is passing it through or not.

And you should connect the bluray player to the soundbar's HDMI input. This eliminates the need of a optical/coax cable. So there is actually nothing wrong with Samsung's connectivity.

Good luck.

 

[scornwell]

In order to test whether the soundbar received an untouched 5.1 signal (meaning the soundbar decodes the audiostream itself), I set the surround mode on the soundbar to AUTO. With this mode enabled, the soundbar turns on a fancy surround effect (which screws up the sound by the way) whenever it receives a 5.1 signal. If the soundbar has received a real 5.1 signal, surround mode ON should sound exactly the same as surround mode AUTO. If not, surround mode AUTO should sound the same as surround mode OFF.

I signed up solely to thank you for that. I've been trying to debug a surround sound issue with my soundbar and couldn't for the life of me work out an easy way of determining what the soundbar was receiving.

For the OP, my testing suggests the Samsung H series TVs will output 5.1 via ARC if the source is internal (the tuner or an app) but for external sources it downsamples to 2.0.