Even analogue out isn't going to get boomy and muffled unless you've set some sort of daft tone control or equalisation, or something else messing with the frequency response. No amount of jitter or noise is going to do that.
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Apple TV 4K sound quality
- Thread starter HairyEars
- Start date
D
Deleted member 48726
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Erhm. No.
- Thread Starter
- #23
I follow the working theory of most respondents here: Jitter is not important since the DAC takes care of it. Close case. Well not so fast, as reality gets in the way. I can pick up in a blind test the Mini+U-DIO8, 6 out of 6. The difference it’s so obvious, it stares at my face.
Science is about observable phenomena. Test, observe, then come up with a theory.
At this point, we’ll just have to agree to disagree.
And thanks for everyone for their input. I'm all the wiser.
Science is about observable phenomena. Test, observe, then come up with a theory.
At this point, we’ll just have to agree to disagree.
And thanks for everyone for their input. I'm all the wiser.
- Thread Starter
- #24
Did that too. Blind-tested it as well. Extremely easy to pick up which is which.
D
Deleted member 48726
Guest
You may have blind tested it but have you made sure to volume match?
Who did the switching for you?
Who did the switching for you?
I was hoping this thread was going to be measurements of AppleTV 4K. 
I assume the MiniDSP U-Dio8 is used to interface between Mac Mini USB-out and Genelec AES-in without a redundant AD/DA step, which looks like a good method. Unfortunate that you don't like the sonics. Like others I'm curious about how/why/if that's happening.
I have considered/hesitated mildly about adding a MiniDSP device in the chain, but haven't need to in the end. Some of them measure better than others. I don't have issues using a Mac as a sound source SQ-wise (ignoring the M1/M2 memory thing). I no longer have an AppleTV device but it used to work well (HDMI-out, of course).
I assume the MiniDSP U-Dio8 is used to interface between Mac Mini USB-out and Genelec AES-in without a redundant AD/DA step, which looks like a good method. Unfortunate that you don't like the sonics. Like others I'm curious about how/why/if that's happening.
I have considered/hesitated mildly about adding a MiniDSP device in the chain, but haven't need to in the end. Some of them measure better than others. I don't have issues using a Mac as a sound source SQ-wise (ignoring the M1/M2 memory thing). I no longer have an AppleTV device but it used to work well (HDMI-out, of course).
- Thread Starter
- #27
I use the Genelec volume control, 9310B, which was untouched during the test.
The dithering is done at the digital domain, inside the monitors.
I go outside the room, and my spouse changes a couple a of cable, after which she cast from my iPad either the MacMini or Aries. She makes sure the display on the Aries is dark before she calls me back in the take a listen. I live in the far east, and the girls here are exceptionally patient…
The dithering is done at the digital domain, inside the monitors.
I go outside the room, and my spouse changes a couple a of cable, after which she cast from my iPad either the MacMini or Aries. She makes sure the display on the Aries is dark before she calls me back in the take a listen. I live in the far east, and the girls here are exceptionally patient…
- Thread Starter
- #28
I was hoping this thread was going to be measurements of AppleTV 4K.
I assume the MiniDSP U-Dio8 is used to interface between Mac Mini USB-out and Genelec AES-in without a redundant AD/DA step, which looks like a good method. Unfortunate that you don't like the sonics. Like others I'm curious about how/why/if that's happening.
I have considered/hesitated mildly about adding a MiniDSP device in the chain, but haven't need to in the end. Some of them measure better than others. I don't have issues using a Mac as a sound source SQ-wise (ignoring the M1/M2 memory thing). I no longer have an AppleTV device but it used to work well (HDMI-out, of course).
Yes, I use the MiniDSP to send the AES signal to the speakers in 5.1 configuration. Works sufficiently well for movies. If I change the GLM profile from the 5.1 preset to 2.1, the MiniDSP will drive the mains in stereo. Then, the sound quality takes a hit, especially compared to my streamer.
My hunch is the culprit is the MiniDSP, but I’d love some Apple TV and Mac Mini measurements too.
BYW, SoundCloud Go+ (256kbps AAC) sounds darn good.
You must have a faulty chromecast.
I was hoping this thread was going to be measurements of AppleTV 4K.
I assume the MiniDSP U-Dio8 is used to interface between Mac Mini USB-out and Genelec AES-in without a redundant AD/DA step, which looks like a good method. Unfortunate that you don't like the sonics. Like others I'm curious about how/why/if that's happening.
I have considered/hesitated mildly about adding a MiniDSP device in the chain, but haven't need to in the end. Some of them measure better than others. I don't have issues using a Mac as a sound source SQ-wise (ignoring the M1/M2 memory thing). I no longer have an AppleTV device but it used to work well (HDMI-out, of course).
I’ve made some basic measurements of my AppleTV 4K in the past but used AirPlay to get the test signal in to the AppleTV. I've always wondered if there is a way to get high resolution signals in to the AppleTV for measurement purposes but haven't spent much time on it.
Below is a FFT of a 1 kHz 0 dBFS tone played via AirPlay from a 2015 MacBook pro into a HDMI to SPDIF extractor into an Okto dac8 pro. This measurement is purely digital and is basically using the Okto as a SPDIF to USB device. I used two instances of REW as the AirPlay playback rate is 44.1 kHz but the AppleTV resamples to 48 kHz. Looks perfect for 16 bit fidelity (~99 dB SINAD).
Michael
That looks great. What HDMI to SPDIF device did you use?
This one from monoprice -> https://www.monoprice.com/product?p_id=24278.
I agree that the extractor works well. It passes up to 4K / HDR10 without issue. Dolby Vision seems a bit spotty if you have match content on so that the AppleTV switches between formats. If you just leave it set at 4K / Dolby Vision it seems fine. Although not sure if this is an issue with the extractor or my TV (Vizio M558-G1).
EDIT: Actually just tested Dolby Vision with match content again and it worked fine. So I guess something must have been fixed in an update to the AppleTV or TV.
Michael
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UDXL2C90
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I got a similar device to 'mdsimon2'. Inexpensive and works well.
With my Apple TV 4K playing to my Sennheiser AMBEO Soundbar, I get 10 channels of "Dolby TrueHD ATMOS ". I use the HDMI connection to my TV. The notation is important because as I understand it, Dolby Atmos is an extension and depends on, one of two Dolby codecs, "Dolby Digital Plus where it is compressed/lossy and Dolby TrueHD where it is uncompressed/lossless.", (ref: Dolby Atmos vs DolbyHD: what's the difference.).Having been exposed recently to spatial sound, I’m considering embarking on that path. Apple TV 4K as the source, playing tracks either off their service or Tidal and into a reasonable quality pre-processor.
...
What can I expect from the Apple TV 4K?
I’m going to spend quite a bit to augment my current system ($10k – $17k, depending on the Atmos layout).
It’ll be a shame if I get a sour apple pie at the end of the rainbow
Regarding Quality: I am looking Apple Spatial Music files at the moment, and all are AAC 256 kbps, @ 44.1 kHz.
EDIT: There are higher resolutions in Apple Music; see my post here.
I expect you have your system by now - hope this helps.
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That only is you have ATMOS disabled.
Not sure what you mean; I am describing the files that are in the cloud, i.e., the data at rest. It has nothing to do with ATMOS as they are not being streamed.
Apple Spatial Music are Atmos encoded tracks (DD+ essentially). If your being served AAC, it’s a stereo downmix.
Thanks for the information. Minor point, DD+ is lossy, Apple Spatial music is lossless, e.g., the highlighted portion of image below.
Apple's definition of lossless is 16 bit /44.1 to 24bit/48kHz and Hi-Resolution Lossless, is up to 24bit/192kHz. (ref: Introducing Spatial Audio, section on Lossless Audio)
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That is not a Apple Spacial Music file that your being served! It's just a stereo file, and you have not enabled lossless quality in your settings, or ATMOS playback. Is suspect that is not the MacOS version of Apple Music?
This is what I get:
If I play with lossless enabled:
If I enable ATMOS:
Atmos on any streaming audio service is lossy!
Note though that the Apple Music app is notoriously bad at switching quality settings. It will seemingly just play whatever it has in cache or download. So if you switch on high-res, and you have an AAC version downloaded, it will just play the AAC version anyway. Also If I enable ATMOS, and download the file, I end up with a high-res version... It's all very confusing.
This is what I get:
If I play with lossless enabled:
If I enable ATMOS:
Atmos on any streaming audio service is lossy!
Note though that the Apple Music app is notoriously bad at switching quality settings. It will seemingly just play whatever it has in cache or download. So if you switch on high-res, and you have an AAC version downloaded, it will just play the AAC version anyway. Also If I enable ATMOS, and download the file, I end up with a high-res version... It's all very confusing.
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Yes, it was not, I did repeat your steps on my Mac and had similar results.
Confusing I agree. I think we are primarily different use cases, e.g., I was using a preview of Apple Music on Windows to send music to a DAC and headphones, and it came through as the file you saw (now below on the right), however when I downloaded the file, we've been looking it it came down as lossless and I played that. It is on the left, the streamed version, which is lossy is on the right (AAC) vs HLS, the encoded ALAC is on the left.
So it appears that what get may not be what the label says, unless you have the correct equipment.
Not sure what "Atmos" means in this context; e.g., when I play Apple Music on an Apple TV and send it to an ATMOS capable sound bar I get 10 Channels of Dolby TrueHD ATMOS (image on the left below). Since Dolby TrueHD is lossless is the whole payload (Dolby TrueHD stream + the ATMOS bit) lossless or does the ATMOS bit come in lossy or lossless versions or is it simply embedded in the lossless stream? On the right is my iPhone over AirPlay to the soundbar which sees 2 channel PCM (right image), I don't know if its lossless or not.
Finally, all the speakers in my house are to playback lossless ATMOS, that will be a bit more work to find out what is actually happening with different devices.
