Apple TV and Audio Quality

Hello,

My Apple TV is used more and more, and right now, its connected with HDMI to my TV`s HDMI hub, and from the HUB to my Naim NDX 2. NDX 2 says the output audio is 48 KHz.

Is there a way to get a higher sound quality from the Apple TV to my NDX 2? As far as I can see, it looks like both the Netflix and Plex app on the Apple TV has support for higher audio quality.

1 Like

Welcome to the Forum. I use the 4K Apple TV with a NDX2 in our lounge and with a Nova in our media room/office. I think the answer is no, there isn’t. I use HDMI to the TV and optical to the Naims. Having said that, I’ve watched a few iTunes 4K Movies with Atmos, and the sound quality has been pretty impressive from earlier iTunes streams, so I’m wondering whether the Atmos streams have higher SQ generally.

Do you Netflix directly on the TV, you could run a comparison. If you have a 4K Bluray, that will output at higher resolution, so that’s an option if it has the Apps you want.

Mike, unlikely, Dolby Atmos is an extension to Dolby Digital Plus, and uses compressed audio streams with spatial grouping and positioning of channels… quite clever I think… The sample rates per channel are 32,44.1 or 48 kHz. However you might find that more bandwidth has been applied to the Dolby Digital/Atmos stream/download master so sounds better as less information is removed.
I do find the audio data bandwidth can vary quite considerably on consumer downloads, with the result the audio can vary.

1 Like

That must be it. I’ve always found the SQ from Bluray well above streaming. It was the new Mission Impossible movie I streamed from iTunes that sounded quite a bit better than I was used to.

By comparison, Roger Waters The Wall on iTunes sounds rubbish compared to a Bluray at 96hz.

1 Like

Thank you for answers! I read something about an HDMI Splitter/Extractor, so you could separate the picture and audio and send the audio via S/PDIF to NDX. But this may not make the audio quality better as i understand.

Im also trying to find out what the Samsung HUB do with the signal from HDMI.

1 Like

How much bandwidth is allocated to audio vs. picture varies.

Last I checked they used HLS which means you will be served a version matching the current bandwidtth you have to the server with content. The less bandwidth you have the more lossy is the compression used. And this may change dynamically while you watch (to avoid dropouts).

So it may be called 4k or hd but the compression when you stream over the net is more lossy than from a blu-ray disc. You could try and download the movie locally and then watch it.

1 Like

I ran that way for a while. The splitter and the through a remedy reclocker to reduce jitter. And then a Naim DC1 to my ndac.

But I get a decent sound anyway so using a reclocker costing more tha twice the cost of the AppleTV was a bit overkill.

From Apple (re. TV 4K):

Audio Formats:

HE-AAC (V1), AAC (up to 320 Kbps), protected AAC (from iTunes Store), MP3 (up to 320 Kbps), MP3 VBR, Apple Lossless, FLAC, AIFF, and WAV; AC-3 (Dolby Digital 5.1), E-AC-3 (Dolby Digital Plus 7.1 surround sound) and Dolby Atmos

Most stereo 48 kHz material should fit into one of those formats and playback without resampling issues, etc.

From my own experience, it is possible to playback the video and audio of a blu-ray at full fidelity. The high(ish) resolution DTS Master and Dolby TrueHD audio streams can be decoded/uncompressed into LPCM with a program like Plex or Infuse.

The splitter is a great idea if you wish to preserve the video fidelity for your display and send stereo audio to the NDX 2.

Do you have a splitter/extractor to recommend?

This is today how it is today:

Apple TV > HDMI > Samsung tv hub > S/PDIF > NDX 2

I was thinking: Apple TV > HDMI Splitter/Extractor > S/PDIF > NDX 2

Thank you, I didn’t know that.

Please excuse my ignorance here.
My Apple TV feeds my TV by HDMI, then the phono audio out goes to my 52. The sound is clear and good to my ears, but am I missing a trick?

Phono Audio out from tv? The new Apple TV 4K has only HDMI.

I would love a little transparency from TV manufacturers about their audio processing. In particular, it would be nice to know how audio introduced to the set via HDMI is handled before being output via Toslink (or whatever).

Things are even more complicated by multichannel sound. How is it being downmixed into stereo? There is some fun desktop software that exposes these processes and even allows some control. Imagine being able to improve these settings instead of them being left to some generic method.

Anyway, check out the HDFury Vertex or a Key Digital splitter with audio de-embed. At least some information is provided! Sticking to stereo-only material will help with the fidelity question.

1 Like

Thank you! this is what I was kinda looking for, I will check it out.

Clarification:
Apple TV’s HDMI goes to Sony TV, phono out of Sony TV to 52

1 Like

Hi Jan, yes HLS is used for adaptive streaming like Netflix and Amazon, but Apple video downloads from iTunes are specific files, (although you can choose resolution) and the bandwidth is fixed irrespective of the speed of your connection for that file.