The difference between Qoboz stream vs purchased songs

"Streaming cannot do this.  Streaming must keep up with the music so streaming always has error management tool that interpolates for any missing bit and moves on"

Depends on the protocol in use.   Certainly UDP by itself can lose packets and so loss has to be accounted for at the application level.  But this is not how data streaming is done these days (and hasn't for some time).

Today, we use RTSP (Real Time Streaming Protocol) or SCTP (Stream Control Transport Protocol) which provides a true IP connection allowing error handling at the network layer, so you rarely lose packets unless your ISP is having an issue.   These protocols even support play, stop, and pause.   SCTP is preferred because it actually breaks the stream into chunks of data and will provide network level error correction, and thus is superior because the packets delivered will be a faithful to the data sent.

To reiterate, if you're having trouble with data retransmission, it's an ISP problem and you can spend an 6 figures in getting the most sophisticated networking gear in your house and will have no impact if your ISP has a problem (or the internet itself is having a problem).

If you think you're having a data issue; before you spend money on cables, special switches and routers, hire a local communication company that can check if you're having packet loss.  It will cost you a lot less than buying new network hear and you'll have data to based your decision on.  

@cleeds this is getting ridiculous, you clearly didn’t read, but here it is again, from David Solomon, the Chief Hi-Res Music Evangelist of Qobuz: “caches the entire track at once.”

https://audioxpress.com/article/exploring-qobuz-high-resolution-streaming

you are 100% wrong. 

fredrik222

this is getting ridiculous ...

Communication is only possible when there is shared definition of words. A zebra is rather like a horse, but it's not a horse. An SUV is rather like a car, but it's not really a car. And a download, a stream, and a cache are three different things in my world, regardless of how they're related. To you they're all the same, and you can't accept a simple physical demonstration (details previously provided) that demonstrates otherwise. So good luck to you.

@fredrik222  That's good information; I know some of the early services did that, and I know spotify does this as well.  I was curious if you download a 192/24 flac that fast, so I did some back-of-the-envelope calculation.

From the article, 192 kHz/24-bit music they allocate 41.9 MB/minute.

Looking through my library, a typical FLAC at 192/24 is about 14 MB for a 5 minute song.

That means that they'll send that song to a user in roughly 3 seconds, assuming the user has sufficient bandwidth.

If you assume a typical home user has a 300 Mb which is (mega Bit) not accounting for the overhead of the IP connection setup that would get you the song in around 3 seconds.   So yes, it's very possible they download first.   I'll have to try that when I get home this evening.

As a pure guess, I think it's likely they're using SCTP because you can let the protocol handle the error correction and breaking the music into chunks.   And then they can start playing as soon as they receive the first chunk of data. This avoids any interpolation of data in the application, and you don't have dropouts waiting for data.

All of this works because music files are tiny, they take almost nothing to move.  It doesn't even stress your internal network.   

It's far more complicated to stream video because we're talking 2-3 orders of magnitude difference in size.

@cleeds So when Qobuz tells you that it's cached first, literally, what do you think is more likely, 1) Your experiment is flawed 2) Qobuz is lying. The answer is obvious.  

They are not the same to me, I know the difference in the technologies, and that is why this matters. You don't. You have demonstrated this beyond any doubt. 

And, even with Qobuz telling you that they cache first, you still refuse to admit that you were wrong. That is ridiculous.