Streaming vs Physical Media

@chopandchange 

Your question about clocking is a good one and it only takes about 2 seconds to get me out of my comfort zone

I'll share what little I think I understand

The issue of clocking is part of an age old problem of jitter in the digital waveform and not specific to streaming, we have the same issue with CD playback, thus the TCP algorithms and protocols may or may not always apply, depending on where the clocking occurs

My limited understanding is one of the mechanism of reducing jitter is improving the precision of the clocking and providing a more accurate digital waveform for conversion and thus improved SQ at analog playback

That seems to lead to various opinions on where the clocking should occur, what device gets to be the master clock, should it be re-clocked and circuitry discussions - ALL WAY OVER MY HEAD

Here's some marketing specs from an audio grade network switch highlighting the advantages of their clocking technology

Specs & Pricing

Circuitry: Fully differential clock circuitry, isolators, and flip-flops
Clock system: Ultra-low jitter/phase noise Crystek CCHD-575 oscillator

I've also seen various stand alone master clock hardware that sits between the transport and the DAC

I've read about one master clock that improves accuracy by maintaining frequency temperature characteristics

Since temperature has a huge effect on accuracy of the crystal oscillator, minimising temperature changes and maintaining it at an ideal level are extremely important in order to generate an accurate clock signal. The CG-10M employs an innovative oven-controlled crystal oscillator, the TEAC Reference OCXO to reduce oscillation frequency fluctuations caused by temperature changes.

What does a master clock do in audio?

The clock provides that timing information and allows the waveform to be reconstructed as an analogue signal correctly when required (assuming the sample rate is more than twice the highest frequency component of the audio signal being sampled).

I find the concepts both amusing and intriguing, does my system need a master clock?

Heck if I know but I'll know it when I hear it, and that will require me to evaluate a couple in my system over time

Hope that helps and there are many on this forum MUCH more qualified than I to tell us both in layman terms the conventional thinking in this space

Happy listening and enjoy the journey

@stevewharton ,

Nicely written post.

Bob

@stevewharton 

Nice summary - and I sort of do get where clocking is relevant from within the streamer or from within the CD player - but before that - no - I don't get it.

At the time of streaming say from Qobuz - the transmission of the data from Qobuz is sent in the correct binary order (courtesy of TCP) to the streamer - so if all the information at the streamer is identical to the information from Qobuz then nothing is lost en-route to the streamer whatsoever! The data arrives at the streamer identical to that from Qobuz.

And when the data is being sent to the streamer over IP there is no need at this point to make a perfect analogue waveform, therefore no clocks needed - just a checksum to ensure perfect data delivery.

Clocking from within the streamer fine - but clocking before the streamer on network switches at the data send stage when TCP is involved - sorry I am still lost. But I sit here open minded and  I am happy to be proven wrong ....

I just don't want us gullible audiophiles to be mugged off.

@chopandchange here's a link to a whitepaper that explains this in better detail, warning is bit head reading but you strike me as quite technical

@gdnrbob thank you Sir for the kind words

@pwayland I have nearly the same digital front end kit with the PS Audio DAC and Network Bridge, using Roon with Tidal and Qobuz libraries, a great source of enjoyment and musical experience

Matching clocks is another often overlooked issue with clocks. Sine wave vs square wave, what freq. running at. I recently experienced what I presume this issue in rather recent negative experience with audiophile switch. I believe John at Uptone has another white paper discussing these issues.