TV data rate seems really high

wiimseb123

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Oct 3, 2024
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For reference, I have my TV connected to the Wiim Ultra via an HDMI arc cable. The Ultra then feeds into a DBX processor/DAC via a digital COAX cable. The DBX then feeds into a couple of amps via RCA cables.

When I play a regular YouTube music video (not YouTube TV or premium) from my TV YouTube app, the data rate reflected on the the Wiim Ultra screen and app, seems really high....2304KBPS 24b-bit/48kKHz. I don't understand why the data rate seems much higher than a CD quality Red Book.wav file of 1411KBPS 16-bit 44.1KHz. I thought regular YouTube sound quality was quiet low...closer to 192KBPS...hard to say because they have their own codec? I notice the same thing on popular videos that review the Wiim Ultra. I'm sure I'm missing something and there is a very simple explanation. Can anyone shed more light on this?
 

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I'm not sure how a TV would resample a compressed file and "spot it out uncompressed?". Am I missing something...the resulting file quality can't be higher than the original file quality? Are you saying that my TV has the capability of upsampling my signal and I'm watching regular YouTube videos at a HD (lossless) quality?
 
By supporting the compressed codec, uncompressing it and resampling it.
Many (most?) tvs output a fixed resolution audio stream regardless of the input.
Sample rate has no bearing on quality, and bit depth is really just about quantisation noise.

If the input audio is 192kbps then you are most definitely not suddenly getting hd lossless audio out of the tv, you are just getting the audio data in a different format. Theoretically it should sound no better nor worse than the original audio. In practice it may sound slightly 'different'.
 
I'm not sure how a TV would resample a compressed file and "spot it out uncompressed?". Am I missing something...the resulting file quality can't be higher than the original file quality? Are you saying that my TV has the capability of upsampling my signal and I'm watching regular YouTube videos at a HD (lossless) quality?
Lossy data compression has nothing to do with decreasing the sample frequency or the bit depth. If you take a Redbook CD and rip it to say 128 kbps CBR MP3s, the bit depth is still 16 bit and the sampling frequency is still 44.1 kHz.

The YouTube video's audio is first decompresses, indeed, by the player software on the TV. It then resamples everything to the usual 24 bit 48 kHz. The transmission from the TV to the Ultra's HDMI ARC input really actually happens at the given data rate of 2304 kbps. That doesn't mean it could make the loss in quality undone.

Back to the above CD example: Taking those lossy 128 kbps MP3 files and any CD burning software you can burn a shiny new Redbook Audio CD from them. The bit depth remains 16 but, the sampling frequency remains 44.1 kHz and magically ;) the data rate is back to 1440 kbps. It's just the content that has changed. It's no longer bit by bit identical to the original CD.
 
Okay, based on the responses, my understanding is that my TV uncompresses and resamples an already compressed audio signal (meaning data was lost during the original compression process) from YouTube into 24-bit/48KHz to reflect the 2304 KBPS on my Wiim Ultra screen. It has not added any quality to the sound that was originally lost during the original compression...just reformats it into 2304KBPS?
In other words, it cuts up the peas on the plate into smaller pieces and arranges them differently...the plate is still same size and more peas are never added... possibly a very poor analogy?
 
Very funny...I like it!

So, one should not assume that a data rate/bitrate of 1411KBPS or 2304KBPS is the determining factor of quality (uncompressed or lossless) sound? It looks like the file type (MP3, FLAC, WAV) is the determining factor, as stated earlier, even a lossy 128KBPS MP3 file can be uncompressed and resampled into 16-bit/44.1 khz 1411KBPS bitrate? In other words, a WAV file at 16 bit/44.1khz 14411kbps is uncompressed/lossless and retains more of the original information than an MP3 file that has been uncompressed and resampled to 16 bit/44.1khz 1411kbps?
 
Different file formats are sometimes called containers, so you might think of a 16/44.1 WAV file as a box that’s full of audio with nothing lost. An mp3 on the other hand has had bits of audio thrown away as it’s compressed, so it looks like the tv is in effect sending a squashed mp3 in a WAV size box ;)
 
So, one should not assume that a data rate/bitrate of 1411KBPS or 2304KBPS is the determining factor of quality (uncompressed or lossless) sound?
And on the other hand you cannot assume that a data rate lower than e.g. 1411.2 kbps indicates lossy quality, because there is still lossless compression. 2-channel 16 but 44 kHz audio may typically have a data rate between 700 and 1000 kbps, but it.is lossless, indeed.
 
So, one should not assume that a data rate/bitrate of 1411KBPS or 2304KBPS is the determining factor of quality
This also means you can stream a hires track from qobuz or tidal at 24 bit and 192 kHz but the information content is still just a normal CD. I suspect that this is actually the case with the vast majority of hires files.
 
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