How to get into high end digital? (Feeding a DAC)

Have been all digital this last 15 years, and my current thinking is that for digital, unlike many of the views expressed earlier, everything mattters.

Simplisticly put, instead of a continuous stream (analog) the music is chopped up (sampled) and then recombined to simulate the original analog stream.  Theoretically, since the sampling is so quick, the ear cannot detect the difference.  What the ear does detect, however, are the inaccuracies in the process.  That is jitter.  Reducing jitter is what it's about.

The recompiling is timed by a clock which emits a 'ping' every fraction of a second. This ping corresponds to a marker embedded during the sampling process in the signal.  The more this is in sync, the less jitter, the purer the signal.  

So all digital devices have a 'clock'.  The better the clock the better your music will sound.  But like everything, there is no magic bullet here. If you feed in garbage, even though the very good quality clock you might have struggles valiantly, it can improve the signal only partially.  So you have to clean up the signal as much as possible before it hits the final clock prior to conversion back to analog. 

This means digital devices need much of the same treatment as analog:

Good powerGood components
Good component support/footersGood cabling
Hopefully, this argument has indicated that timing (reduced jitter) is all important in digital systems. 
And finally, here is the good news for those of you who have managed to get through all of the above:  After all this, you can STILL get the signal reclocked and cleaned up hugely by a relatively new device...the audiophile switch.  The reclocking in them is far more accurate than the clock in most DAC's.   They work even better in a cascade (series) as each stage cleans up the signal more.  Price for these switches vary from usd 700/- to many thousands. 

My system comprises router/NAS > streamer > dac with 3 audiophile switches in series prior to the streamer. The addition of each streamer marked an large order of improvement. 

Most audiophile switches come with the capability of using fibre optic (which can be immune to electrical effects) instead of copper wire, but that's another story.  

So, once you got the basics sorted, i.e. storage device, streamer and dac, to get to serious high end sound you should clean up the signal more with audiophile switches.  This will help no matter how high end the clock in your final digital component, the dac, is. 

The never ending story here is using external clocks!  These are accurate to atomic standards and there is a whole cult built up around implementing them.  My first one arrives in a couple of weeks!

Best wishes, and hope this diatribe has been of use.  I have avoided talking about branded components to avoid the appearance of shilling.  My 2 cents.

I would start with one switch. See what happens.  Top end switches start at circa 700/- so its not as if it would break the bank.  Check out reviews.  See what other people say about that item.   Not to be disloyal, but I find whatsbest and audiophilestyle are easily the most informative forums for things audio. 

Why does good support improve sound?   That's easy.  There are a few thousand itty bitty pieces of stuff in an amp (or any electrical unit) - things like capacitors, rectifiers, resistances etc.  Each of them vibrates a tiny bit at their own resonant frequency in response to the vibration from the music and transformers, etc.  This generates their own tiny signal in the overall electrical field of the amp.  Thousands of these conflicting signals are feeding into the main signal.  That's emi inside the unit = hash.  There are various ways of dealing with the vibration....you can use mass for damping, special materials to line the walls of the unit, springs to try to make the  whole unit move as one in response to outside vibration, cones (they are like mechanical valves) to block outside vibrations.  On top of the vibration from speakers, a fun fact to keep in mind is that Earth is constantly at Richter 1-2. 

In my opinion, the best are those devices that drain entropy, preventing transfer of vibration into the component and at the same time cancelling internal vibration.  They also work for speakers by decoupling them from room effects.  In fact, it is with footers for speakers where I found the most significant improvements.  Relatively expensive, but worth every cent.  

I've elaborated a bit here because, in my opinion, these particular sub species of footers along with audiophile switches are both the best bang for the buck in audio at its current state of development.  They are SOUND QUALITY amplifiers, even for relatively cheap equipment.  Much smarter upgrade path than buying more expensive equipment.

Not sure what magnetic platters do....I have never used one.

Good power cords block emi and clean up the signals and improve SQ in ways that I don't really understand, but have empirical experience of.  Its easy to test this.  Just try to compare a couple of ac cables, give them ten minutes of play time before judging.  You should get a taste of what you will finally get after 5-600 hundred hours of usage (this is a dead crazy hobby we have got ourselves into).  Again, there are great ac cables starting at circa 200/-.

Hope this is helpful and not too long winded.

Best wishes