why expensive streamers

Far too much sense being talked here: I think I need to find a thread with a bit more nonsense!

Some great posts.

The streamer is the first point at which timing (jitter) becomes a thing. It's job is to unpack the packets/frames of data which arrive asynchronously and convert them into a bitstream. An highly accurate clock at this point can have a huge impact on sound quality, as of course can the streamer not adding in unnecessary noise which won't make any difference to the 1s and 0s but if it reaches the analog(ue) parts of the DAC then it very much can.

I still only have a modest Innuos Zen Mini with a souped up Zen Mk3 LPSU but the improvement in sound quality over my Bluesound Node 2i is clearly audible, and that's despite the latter having been "pimped" with a Sean Jacobs DC3 linear PSU and a Mutec MC-3 reclocker.

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...

@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

 @cleeds Quite possibly but if ethernet protocols didn’t sort this then the internet wouldn’t work. Error checking and correction are built in. The streamer input side deals with this so the output side doesn’t have to.

@steakster I’m really not sure that’s “as I wish”; I’m a listening first guy who then seeks to understand the physics/science which might explain what I’m hearing but the SR stuff is from a different planet. What the heck are “contouring” and “tuning” actually supposed to be doing to a digital signal? Modifying the 1s and 0s which amounts to corrupting the data? Changing the timing? Or modifying the way in which RFI noise accompanying the digital signal is handled? This sounds like leading edge witchcraft…

@grislybutter Cool, glad to help. The signal coming out of the streamer containing 1s and 0s does incorporate a timing element. Jitter is therefore a “thing” from the streamer onwards in a way it isn’t up to that point.

@carlsbad2 Seriously, I'd suggest you read up on ethernet. The built in error-checking, retransmission etc will ensure no bits are dropped. The primary concern about ethernet data transmission from an audio perspective should be minimising noise accompanying the perfect digital signal which reaches your streamer.

@invalid It's true that a purely digital doesn't exist as such, it's an electrical waveform. What happens from the streamer output side onwards is subject to different constraints, factors etc from what happens in the ethernet domain ie everything up to and including the input side of the streamer. In this ethernet space, all devices translate the electrical signals into 1s and 0s. If folk talk about the angle of the wave, the timing of the wave etc then they don't understand how ethernet works.

SO while you're technically 100% correct, talking of waves can get people musing on all sorts of stuff about cutoffs and curve sharpness etc which are totally irrelevant in ethernet.

@jaytor Agreed re how much measurements can tell us and how they may or may not correlate with what we hear

Thanks Jerry @carlsbad2.

Any materials you can point me/us to? I presume this is in the public domain.

Best,

Nigel

Thanks again Jerry @carlsbad2 

“Streaming can’t use the error checking protocols that achieve bitperfect file transfer. Thus, dropped bits and the streamer’s attempts to deal with it. Otherwise, there would be no market for high end streamers, silver digitlal cables, or anything high-end digital audio.”

Jerry, apologies, I do recall your first related post but didn’t realise you were the same author. For a self-professed non-expert on streaming, they’re quite some assertions!

Perhaps you should forget the network tech googling thing and find somewhere where a streamer manufacturer says something about why they can’t use the same error correction techniques/technologies as other ethernet-capable devices. I don’t recall having read anything from Antipodes or Innuos or dCS or similar where they talk about how they’re much cleverer at working out how to fill in the dropped bit “gaps” than their competitors. I suspect you won’t find anything as it’s not a problem they’ll recognise but, hey, what do I know, I’m just another internet rando like you!

Until I see anything from a streamer manufacturer/designer which corroborates your suggested explanation of the differences in sound quality amongst streamers, I’m going to stick with my own assertions that ethernet data transfer IS ethernet data transfer full stop (US period) and that streamers differentiate based on noise and clocking (possibly amongst other factors).