Poor sound quality via TV optical output

[Yoni842]

The first thing I'd try is simply using the Samsung TV for sound. Does it sound good (I mean good for a TV, not compared to your speakers)? Dialogue is clear, that kind of thing.
.

Yes it's sounds good enough, no distortion or so. I doubt it has something to do with the optical cable considering the really cheap price of that converter, and unfortunately I don't have another one.
The poor sound quality isn't present on Netflix only, but also the other apps like Spotify and so.
Can you possibly think of a decent DAC that would maximize my speakers potential (Microlab Solo 7c)?

Looking at the price of that thing, I'm going to say that DAC is probably terrible. I've used the optical out on my LG TV for ages and it sounds perfectly fine. But you should really test it with something else first to make sure where the issue lies.

Yes, probably this DAC is a junk. Although we're talking about Samsung TV so I'm not sure if it's the same case.

 

[SimpleTheater]

Can you possibly think of a decent DAC that would maximize my speakers potential (Microlab Solo 7c)?

I'm hesitant to recommend another DAC converter without first testing that optical cable. However, if you do get another converter, I'd strongly recommend you get it from somewhere that has a 30 day no questions asked return policy. I know the unit you bought was cheap, but it should have worked since there are so many good reviews on it (could be defective). You might want to try this one, but its still a cheapie.

 

[Vict0r]

I've used a Fiio D3 optical to rca converter for a while and was very satisfied with it. Excellent sound, super easy to use. Paid $50 for it or something. TV => optical out => Fiio D3 => RCA out => stereo amp => passive speakers.

 

[Pluto]

I would be inclined to try playing something like this to ensure that the TV is making a reasonable job of presenting content (that might be in heaven only knows what format) in the 2.0 state that will be required.

I suggest you do your testing using known, simple format test content such as a news station. Only when you are sure this is working correctly, carry on with more sophisticated formats. It is possible that the optical output is not making a particularly good job of “folding down” fancy formats into the 2.0 that your listening system requires.

As an addendum to the above, I suggest you download any test material and play it locally, as it appears that anything you play on YouTube's web-based player will be folded down to 2.0 by them, and thus be of little value in checking whether your optical output is actually doing the job required of it.

 

[Denali]

I have a similar problem. I have a LG OLED C8 and to that I have a Apple TV and a Playstation 5 connected and am outputting the sound through the optical port to my Marantz PM6007 amp.

I have a two channel setup and the TV is set to PCM and when it get a multi-channel audiotrack from the apple tv or the playstation 5 the sound is thin and sounds hollow. Like if it is just dropping all channels in the multi-channel track except for the L/R channels. However, if I set the Apple TV to output stereo instead of multichannel it is a massive difference and I get a really good and deep sound. The Playstation 5 however doesn’t seem to handle this properly since even if I select two channel audio in its settings it sounds the same with the thin and hollow sound. The same goes for the LG WebOS internal apps on the TV. I have tried it on material from the Apple Movies app and the Netflix apps that I have on all three sources (Internal TV app/Apple TV and PS5). The difference is huge and it is only the Apple TV set in stereo output that seems to downmix this properly.

There must be some setting that can be changed for this to be handled correctly since I have a hard time believing that all people with two channel-systems accept this rather thin and hollow sound through their TV setup.

 

[Denali]

I've used a Fiio D3 optical to rca converter for a while and was very satisfied with it. Excellent sound, super easy to use. Paid $50 for it or something. TV => optical out => Fiio D3 => RCA out => stereo amp => passive speakers.

I can also add that before i got my Marantz PM6007 earlier this week I had this exact DAC to my old Rotel RA-05 amp. It was exactly the same issue there. I was hoping that the cheap DAC (Fiio D3) was lacking and the better DAC in the Marantz would solve this, but it is the same.

 

[ZolaIII]

Thing is we really can't do anything about how OEM's implemented the bit stream to PCM conversion or downmix. And even if it does that correctly how much lag it will add. At best you can buy a DAC which will do that part correctly. Unfortunately that narrows the selection dramatically.

 

[Martin]

I think this is your problem:

Here is a link to this cheap crap converter:
https://a.aliexpress.com/_v3i9KL

Try a real DAC - maybe a cheap Topping, Geshelli or JDS.

 

[Denali]

I think this is your problem:


Try a real DAC - maybe a cheap Topping, Geshelli or JDS.

But if that was the problem wouldn't me switching from the Fiio D3 to the Marantz PM6007 have solved it? The Marantz have been praised for its DAC but regarding this issue it is the same result as with the Fiio D3.

 

[Pluto]

I have a hard time believing that all people with two channel-systems accept this rather thin and hollow sound through their TV setup

Let's assume, for a moment, that the audio sent to the optical output is fundamentally the same audio that gets delivered to the TV's two internal speakers. In other words, that there is no extra folding-down or other processing performed en route to the internal speakers compared to the optical output. NB if anyone feels this assumption is erroneous, please speak up!

Obviously, the silly internal speakers will be thin and nasty but the most important thing to check is that most dialog is being correctly delivered to the optical output. This is why it is essential to start with the most simple of formats as transmitted by a station (or a local data file) that neither knows nor cares about anything other than 2.0.

When (and only when) that test proves successful, the next thing to try is 5.1 content with a view to determining what the TV's internals are doing with the all-important center channel. Check the internal speakers first, then the optical output. If the center channel is getting lost somewhere in the process, dialog will be (more or less) non existent.

I would find it hard to believe that any modern TV isn't, at the very least, processing incoming Dolby Surround so that the center (dialog) is split equally to the left and right internal speakers and, hopefully, in a similar manner to the optical output.

 

[Yoni842]

I would be inclined to try playing something like this to ensure that the TV is making a reasonable job of presenting content (that might be in heaven only knows what format) in the 2.0 state that will be required.

Ok so I played that sound test, but I'm not sure what I suppose to look in to? Overall the sound quality is still "flat".
However, I tried to play a certain song either on Spotify and Youtube apps, and I noticed that in Spotify the sound was lowder but it kind of got distorted at the highs, and like it had some artificial amplify to it. In the other hand, the same song in Yotube sounded cleaner but less loud, and no distortion.
I also played music (320kbps mp3 files, if it matters) via an external usb hard drive that I connected to the TV, and it sounds Ok, but still it's like "flat" no depth to it, no loud bass. I well remember how was the sound when the speakers were connected to the PC which it was great at that time. Nothing like now.
I think I'm having the same problem that @Denali has described very well.
I'm starting to think that there is nothing I can do about it.

Do you think this product will help somehow? Being Dolby Digital/DTS compatible?
https://a.aliexpress.com/_uJnXmj

 

[Pluto]

Try a real DAC

Forgive me, but the primary mission is to answer this question: is the content being presented to the DAC what it is expected to be?

Only then is it worth delving into the subtleties of sound quality.

 

[Denali]

Forgive me, but the primary mission is to answer this question: is the content being presented to the DAC what it is expected to be?

Only then is it worth delving into the subtleties of sound quality.

I absolutely agree with you, and thank you for your help. I will do some tests with the internal speakers as well as normal 2.0 material and report back!

 

[Pluto]

Ok so I played that sound test, but I'm not sure what I suppose to look in to?

First, did you download this file and play it locally (i.e. not via YouTube's web player that is likely to mess up the very area you need to check)? You need to ensure that the left, right and center audio reproduces at roughly the same volume. Don't worry for now if you can't hear the surround left and right or the subwoofer stuff, the deep bass.

Even then, unless you have technical knowledge to check that the audio content of the file you have downloaded really is correct, this may not help. I am not concerned, at this stage, whether you perceive the quality as "flat" or otherwise but we need to establish, beyond reasonable doubt, if your optical output is doing anything to be the cause of your unhappiness. If the optical stream is not correct, all the DACs in the world won't help.

Check again on the TV menus that the optical output is set for basic 2.0 PCM, no Dolby, DTS or indeed anything that might require external processing.

 

[Martin]

But if that was the problem wouldn't me switching from the Fiio D3 to the Marantz PM6007 have solved it? The Marantz have been praised for its DAC but regarding this issue it is the same result as with the Fiio D3.

I was responding to @Yoni842; I did not realize there were two separate discussions happening in this thread. It sounds like there are issues with audio pass-through on your LG. I think the OP was having problems with audio from the Samsung TV and apps running on it. Two different problems other than you are both using toslink. I stand by my reponse - that linked "DAC" is likely junk.

Martin

 

[Pluto]

I have just downloaded this file from YouTube, which purports to be a 5.1 test tool. However, the audio on the download is 2 channel, albeit a reasonable fold-down from 5.1 (if indeed the audio on YouTube's server ever was 5.1).

So right now I am at a loss to know where to obtain some test audio capable of checking exactly what this TV is doing to source material >2.0

 

[Yoni842]

@Pluto
I played the "HE-AAC Channel ID - with H.264 Video" in that link: https://www2.iis.fraunhofer.de/AAC/multichannel.html
Everything sounds right, except for when the sub plays alone, I'm not hearing anything, but I guess it's ok?
And yes, I double checked that the audio output set on PCM.

Edit: I found this site too: https://www.audiocheck.net/audiotests_frequencychecklow.php

I don't now exactly which test I should play, but after trying some I noticed that the male over voice in every test sounds like distorted/cracked like there's a "vvv" sound, and it's similar to what I've experienced when playing music in Spotify app, like I've mentioned earlier.
Is that helps somehow to better understand the issue?

 

[Pluto]

Everything sounds right, except for when the sub plays alone, I'm not hearing anything, but I guess it's ok?

OK indeed. Having proved that the correct audio is coming out of your optical port, it is now a case of finding out why the quality is not what you expect. With this aim in view, I would find a digital source rather more consistent than a TV*; get some suitable demonstration material to assess which components are to blame and eliminate each element in the chain in a logical and consistent manner, entirely by ear. Forget about “specifications”.

*If you don't have a viable digital source, look for a CD player with a working digital output. You should be able to pick up such a player for next to nothing.

 

[Denali]

Forgive me, but the primary mission is to answer this question: is the content being presented to the DAC what it is expected to be?

Only then is it worth delving into the subtleties of sound quality.

When I try 2.0 content from the Apple TV or the Playstation 5 it sounds as it should. When I change and try 5.1 material it sounds good when the apple TV downmixes it to stereo but not when I leave it to the TV or Playstation 5. I shall also test with the internal speakers and see how it reacts to the differences. I'll report back regarding that.

 

[krabapple]

When I try 2.0 content from the Apple TV or the Playstation 5 it sounds as it should. When I change and try 5.1 material it sounds good when the apple TV downmixes it to stereo but not when I leave it to the TV or Playstation 5. I shall also test with the internal speakers and see how it reacts to the differences. I'll report back regarding that.

That suggests that the TV and Playstation are not set to downmix the content correctly.