Qobuz Connect

For me, the most interesting thing about Qobuz Connect is its ability to switch end-point players mid-stream.  For example, I'm playing a track on my phone using my headphones while out for a walk. Then I go through the front door while halfway through the song and switch playback to my main stereo without missing a beat.  I could even go to a friend's house, who does not have a Qobuz subscription, and play my Qobuz tracks on his stereo if he has a QC compatible streamer connected to the internet. 

While interesting, I really don't have a big use for this feature.  I also don't hear any difference between QC and my other playback program options -- the digital music stream still has to travel over the internet direct to the player.  QC is a nice way to select and play music, but it is limited to only that. It has no way to play from your local collection. 

@cleeds

Maybe I am simple!

Qobuz has long had its own app to run on Windows, iOS, and Android

My guess is that there are at least three different Qobuz end-point apps, though they may share some code and have similar user interfaces.  If Windows, iOS and Android users want to run external DACs, the data communications links to those DACs are outside the Qobuz ecosystem, and outside any claims that data is perfectly transmitted because TCP is used end-to-end.

Writing a Qobuz app to run on each DAC makes sense because it can extend TCP error detection and recovery to the box containing the DAC.

What about streamers that run a Qobuz app but with external DACs?

richardbrand

My guess is that there are at least three different Qobuz end-point apps.

Yes, that's what I said: Windows, iOS, Android. Details here.

... Writing a Qobuz app to run on each DAC makes sense ...

The software is in the streamer, not the DAC.

Innuos told me that QC does not use it's internal playback engine. It bypasses the internal system Sense uses and uses it's own software incorporated into the Pulse firmware. So some of the variation in performance must be related to how QC is installed in each streamers firmware. 

@cleeds 

No, you said "its own app" when there are multiple implementations. You and Qobuz imply there is a single app.

I am trying to find reasons why people might hear differences, and having multiple implementations allows the possibility of different bugs in each implementation!

When I said "Writing a Qobuz app to run on each DAC makes sense" it was because it gives TCP a chance to deliver bit-perfect transfers to the device that does the final digital to analog conversion.

(TCP does not stand a chance if network congestion or dropouts exceed local buffer capacity)

Delivering to a streamer which then has to communicate digital to an external DAC creates more opportunities to introduce uncorrected digital errors.  For example, I2S does not have any error detection or correction ability.  There is no guarantee the DAC receives the original digital.  USB has a special mode for streaming which has no error correction.

Forgive me for not trusting Qobuz but their website states 

An analog audio signal is composed of a sine wave, like an electrical signal. A digital signal is simply the reproduction of this sine curve which represents the sonic wave

This is a gross oversimplification as anyone familiar with Fourier analysis can attest.  Arbitrary repeating waveforms can be represented by the sum of an infinite series of sine waves, being the odd harmonics of the fundamental.