why expensive streamers

If we focus purely on the 1's and 0's arriving at the DAC in the correct, unmolested sequence then we can relax as all streamers will sound the same; all we then need to do is pick the streamer with an app/user interface which we like most.

Unfortunately, streamers also incorporate clocks so the sound quality they help produce may be affected by there being more or less jitter.

Unfortunately, streamers vary in the amount of noise they generate or pick up and this noise reaching the analog(ue) parts of the DAC will also affect sound quality.

If noise wasn't a thing and jitter wasn't a thing, all streamers would sound the same.  Unless I've missed something, and I'm sure someone will be along shortly to politely enlighten me if so...

@cleeds hope dies last :)

@nigeltheflash I am sorry I am slow and thick. This is too abstract for me. And let's just focus on the "noise". 

Noise from where? The machine noise? Noise in the signal?

The signal comes from a server. Travels through a lot a steps, finally arrives to a streamer. Does the streamer add noise? Or it knows how to remove the noise?

And a good streamer sends "clear" signal to the DAC?

Sorry, feel free to ignore me. Just trying to understand. 

Theorizing why a streamer should or should net have a major effect on the sound quality is like theorizing on any other aspect… it may not make sense logically… until your jaw drops upon hearing a good one. I have heard at least a dozen in controlled circumstances and the difference is like between a VW bug and Porsche… night and day difference in performance. 

@grislybutter Slow and thick? I doubt it!

RFI noise accompanying but not part of the digital signal. It can arise anywhere along the playback chain and is why many people choose to incorporate an optical connection or a switch close to their streamer.

You say the signal comes from a server; sometimes it does, and sometimes it comes from a router. Both require a streamer to unpack the packets into a stream of 1s and 0s.

Some streamers simply pass the noise on. Some might add their own (do they have noisy circuitry? does this include LEDs?). Some might incorporate the sort of galvanic isolation we see in switches so actually mitigate the noise they receive and pass only some or none of it on.

So yes, a good streamer sends on to the DAC as close to the purely digital signal as it can. I’m not sure "clear" is the right word, as this might suggest that some streamers send more accurate 1s and 0s than others and it would be a truly terrible streamer which shuffled these!

The effectiveness of how various streamers handle/address noise is therefore a key factor in their performance.

The second thing a streamer does it to add a time signal to the bitstream it creates from the data packets/frames it receives, but this is a separate point.

Does this help?

Nigel