Extracting/splitting HDMI audio

[MassiveJim]

I have an LG C9 and a Marantz NR1504, because of this all of my sources are routed through the TV and use ARC to transmit sound to the receiver.
However there is a small issue that every now and then the sound will drop out for about a second and its highly annoying.


I was on the hunt for a newer receiver that supports eARC but have just discovered that LG haven't properly implemented eARC and there are issues with it.


So is it possible/easy to split the audio from a HDMI source and send it directly to the receiver ?

When I have searched online it seems to be a "box of tricks" that handles this, I don't know enough about the standards and cables to know exactly how it works but in my head you could have some kind of splitter cable that just took the audio channels so that you could send them seperately to a receiver.

Also apart from the HDMI output on my TV how can I get audio from the TV to the receiver (For netflix/Prime/TV/etc)

Please educate me

 

[MassiveJim]

You've already answered your own first (1) question because you've found boxes that split the audio.

The answer to your second (2) question has a few parts. The most important bit is to understand what the TV does with the audio it gets. i.e. "does the sound format stay the same or does the TV change it?" The answer as far as ARC and Optical goes is it changes it. Any HD audio formats get dropped to the standard lossy versions, so Dolby True HD gets reduced to standard lossy Dolby Digital.

HDMI ARC is limited in what it can do with sound. There are also some additional limits often encountered because of the way TV manufacturers decide to handle DTS audio: Luckily, your C9 is one of the few TVs that will pass through DTS 5.1 unchanged.

eARC can pass HD audio, but as you'be found, LG hasn't set this up right on your TV.

Next, marry that bit of info up with the sound capabilities of your receiver. It can do everything up to HD audio. Being a 5.1 receiver though it doesn't have much use for anything that involves Dolly ATMOS. That's not a problem though because anything that is encoded for ATMOS will play in the highest grade 5.1 version by default.

Now look at your audio signal sources. You'll have apps on the TV (Netflix, Prime, catch-up TV maybe?). The TV sound itself from Freeview/Freesat if you're using those. Then there are any external sources you might have such as a console or video disc player.

Netflix and Prime output Dolby Digital 5.1 (DD5.1) as it core high quality format. ATMOS is supported by DD+
Freeview and Freesat output DD5.1 at best
Sky Q the V6 Virgin Tivo boxes output DD5.1 as best core format, and DD+ for ATMOS
Consoles can output multichannel uncompressed pcm in up to 7.1 format, or be set to convert that to DD5.1 or DTS5.1 . I know there was talk of games having DTS:X which is the ATMOS version of DTS-HD Master Audio, an uncompressed HD audio format.
BD players and UHD 4K disc players will output Dolby Digital TrueHD and DTS-HD Master Audio and the ATMOS and DTS:X versions

All of the above in contingent on the programme you're watching or the game you're playing or disc you're watching having the audio encoding.



So, pulling all this together means that to get the best sound from your external sources such as a disc player or Firestick or console, you should put the signal through the receiver and let it deal with sound.

Routing everything via the TV and using either HDMI ARC or Optical Audio will still give you DD5.1 and DTS5.1 as the best audio from the TVs own streaming apps and internal tuners which is really all you need. However, ARC and Optical won't handle HD audio, so that means you're losing sound quality from any source that carries Dolby True HD or DTS-HD MA.

There's no problem having the TV use either ARC or Optical. They both deliver the same quality of sound. HDMI ARC has the advantage of being able to communicate with the amp so that the TV can control the amp volume.


Trying an audio stripper on the eARC output of the TV might work so long as the TV sees it as a valid eARC sink device. TBH though, it seems like a lot of hassle to go through just to get HD audio from a source that could easily be connected to the amp first then the TV without all the cost and hassle of an audio stripper.

Is there a simple cable that will extract the hdmi audio (hdmi splitter) I can run one cable from source to TV and one to the receiver

I use Netflix on the TV a lot which means I'm getting compressed audio (along with these annoying sound drop outs) I assume the only way to get better audio is to watch Prime/netflix etc on a seperate source such as a firestick.

Sources are xbox (series x is on preorder) and a HTPC
currently have a ps4 on loan from a mate as well