Understanding Bluetooth and WiFi Audio or Lack Thereof.

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DWD1961

[H]ard|Gawd
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I just wanted to open some dialogue related to BT and WiFi audio, mainly with BT codecs on the devices side related to audio quality.

This isn't a discussion about latency. It's only about audio quality, and yes, we all know that if you want the best quality, use a lossless codec on a wired system, or use the source material, CD, Vinyl, etc. So, please, let's not degrade into any of those arguments. Except for a very few 'audiophiles' sitting in their sound proofed basements with a $10, 000.00 Vinyl record player and $20,000 "tube amps" and 50K speakers, wireless music really is the future, much like Vinyl gave way to digital CDs and CDs have given way to digital files. Like it or not, it's the way it is. Also, it looks like BT will be the future, not WiFi for audio transmission. Sure, yuo can stream music from your router to your computer and tehn hardwire yuor computer into speakers, and we can discuss WiFi options for home audio use.

So far, my limited understanding or not even understanding all of the nuances is thus:

  1. Using BT, you are going to be either compression or re-compressing audio data, depending on the devices support of codecs.
  2. If both the source and destination (sink) support the same codecs, then the file should be transferred as it would sound on a wired system (given bandwidth is not exceeded and the radio signal is clean). For instance, if you have a device and source that support AAC, then the original AAC file should transfer it's original AAC data to the sink (destination).
  3. All BT devices support the SBC (2003) compression standard. All files that do not have a device to source codec match will be re-compressed to the SBC format.
  4. Almost no BT devices support MP3, so in those instances, the source MP3 will be converted to SBC be the destination device.
  5. Converting from one compressed lolly format to another decreases quality. So, even if you are streaming FLAC lossless, unless the source device supports that codec, it's getting compressed to SBC.
  6. Wireless or WiFi 2.4 and 5Ghz do not have this problem and if you have a WiFi device at the destination, does not convert the original data, but simply "passes through" the data to the destination device, which then passes it uncompressed to speakers. This is not Bluetooth, though and requires a router to work. (I had an old Sound Blaster WiFi dongle and small receiver that plugged into the audio receivers AUX port, for instance.
What this means to me:

If I have any of it correct, is that until the SBC standard is updated, almost everything you stream to a device is going to be re-compressed to SBC, given that the devices are not using the same codec for source and sink. (LC3 is suppose to be the new BT default for BT 5.2.) SBC is no slouch, and is arguably better than MP3, especially at high bitrates.

What I am confused about: If you have a BT 5.1 card in your system running Windows 10, does Windows do the converting when sending the data, and the card just passes that stream on t the device or the card itself? For example, the Intel 9260 card's WiFi/BT is BT is 5.1, but no other codec specs on it. Of course, it's a source/transmitting device, not a receiver device. So, yeah, confused about that.

Last, are there any WiFi options that you can plug into AUX ports on a receiver anymore? It seems like BT has taken over. 'd like to have a WiFi receiver to plug nitomy receiver for home use, as I mainly stream miusic--and as discussed, thta's getting REcompressed into SBC in most all situations.
 
It is the future, but we're still waiting for something better than AptX HD to be widely available, which I feel is still something muffled sounding and despite the claimed bitrate sounds worse than a low bitrate MP3 most of the time.
 
pippenainteasy said:
It is the future, but we're still waiting for something better than AptX HD to be widely available, which I feel is still something muffled sounding and despite the claimed bitrate sounds worse than a low bitrate MP3 most of the time.
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That's what I have read also, and I've listened to samples too. Not really impressive. I think aptX's clain t fame is low latency. SBC is horrible, about 170ms. However, sound quality of SBC is pretty damn good. The engineers behind SBC really did a fantastic job given ow power constraints and re-converting with as little extra loss as possible.

I'd just like to find a WiFi AUX processor. That way I know everything i feed to it is coming out like it was iriginally encoded, given a clean WiFi signal.
 
vegeta535 said:
Average person doesn't care about quality. convenience is king too people.
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It's important enough that developers and organizations are working to increase the quality of BT audio. Really, and sadly, BT is all we have for wireless music that doesn't require an intermediary router--which makes it locally wireless, but not mobile wireless, that is, independent of router necessity. I mainly listen to music at home, while I work, between two nice Klipsch speakers at a distance of 9' feet and 3' high directly between the speakers.

Most people don't have the equipment or ears to hear the differe3nce between a 320Kbps MP3 and a CD ROM. However, you can in some instance hear the difference of a 128kbps mp3 with teh rght music and if you have equipment plugged directly into the lossless source using the same codecs, and given you have no outside background noise canceling the extra sound information. But, those 3.5mm jacks are going away, and most of us don't listen to music in a sound proofed room using high end gear. I've listened and listened to high quality MPs (194kbps) vs CD ROM and i can't hear any difference in a high quality mp3 and CD quality. You definitely won't hear it in your car driving down the road. However, sometimes, depending on the song dynamics, yeah, you may hear some differences but nothing sustaining, and nothing really acoustically bad. It's just different. That difference really doesn't bother me because I'm not a machine.

What does bother me is hear a flat reconstruction of the original where the midaranges are muddy or there is no separation of instruments. Now that's really annoying, and very boring to listen to. Re-configuringa 128Mbps MP3 that sounds pretty decent into SBC is one of those instances. The problem is that most streaming audio is still 128kbps MP3. I've read that SBC is constructed to find and preserve aspects of MP3 that would otherwise sound terrible re-compressed, so there is that. My listening tastes have changed over time and now that I listen mainly to jazz, I need those mids back and clearly. Hard rock or rock in general, or Blues, not so much. But jazz lives in the mids.

Like I said above, Sound Blaster, back before Bluetooth took over, had a wifi sound card dongle and transmitter, and a remote receiver you could plug into your AUX on a receiver. I'm wondering if anything like that exists today.
Creative Labs Sound Blaster Wireless Audio Transmitter and Receiver (not Bluetooth)
 
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vegeta535 said:
Average person doesn't care about quality. convenience is king too people.
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I used to be a die hard audiophile. But since I upgraded my macbook I find more and more that I'm just listening music through it. It gives a surprisingly good stereo imaging on most music. Of course the frequency response sucks but its... convenient.
 
Well it is not that customers don't care about quality. It is they are mostly ignorant to how much better something can be. They don't care about researching more into something because what they are use too is good enough for then.
 
vegeta535 said:
Well it is not that customers don't care about quality. It is they are mostly ignorant to how much better something can be. They don't care about researching more into something because what they are use too is good enough for then.
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That's right. it sounds good enough to them. Back when I had a nice system, I listened to 192k-320kpb MP3s encoded with the LAME encoder and CDs and I could literally not hear the difference 99% of the time. And, when I thought I did, it was just a fraction of a second. The problem is that when using BT, everything is getting re-compressed or at least reconverted. Most online stuff or even stuff you buy in a digital format is still mp3 and probably will be for a long, long time. BT doesn't even support MP3. It's MP2-converted to SBC, and fuck you if you don't like it. Actually, SBC is probably even better than MP3, but who converts music to SBC? I don't even think I've seen that format in a converter.

BT does do a 1 to 1 for AAC, so if you have an AAC file, BT will just transfer it without converting. I should do some more research and figure out the actual process of MP3 to BT SBC conversion quality loss.
 
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