This is a great topic and we have covered it here and there in other threads. There are many factors involved and many (most?) we really don’t understand yet. Commercial servers are often small, low powered (CPU-wise) embedded systems. How they are powered (power supply) and filtered varies and storage is either spun or HDD. Software may be Linux or a variant of Windows and either will then run music server software from a variety of sources (some, I suspect, in-house but many use either commonly available programs, like JRiver, or perhaps variants). This capsule description is overly simplistic and there are systems out there that do not fit in these broad categories. My point is that there is not any “magic” inside these boxes, just carefully tuned computer hard/software, much of which is available on the open market. Some look “computerish” and some don’t but that is essentially all that they are.
There is little disagreement on whether big CPU’s or little CPU’s are better. Either can be made to sound pretty darn good but it takes some experimenting to get there. Remember, just because many servers are low powered systems does not mean that this is the only way to go. These companies are looking to make a profit and that style of hardware is really, really cheap and compact in comparison to, say, an i7 based machine. I’m not saying that one is superior to the other, just that if I was going into the server business, I would choose the more economical solution. I use bigger hardware because I am more familiar with it. I have just gotten a new i7 K processor that I can under clock and under volt. Hopefully I will come up with similar improvements to what Wijnand has gotten with his setup. The CPU under volting made an impressive improvement in my server and the under clocking may be an even bigger jump. Of course all that may be just peeing in the wind in that it just brings the big, electricity hungry processors down to Atom processor range at greater expense.
If you are working with a laptop, your range of tweaks is limited. IMHO, the easiest way to get to better sound in your situation is to try Fidelizer with the music player software of your choice (I use Minimserver) and shut down any other programs running, like Explorer, Word etc… Give the free version a shot. I use the Pro version and it does sound better. I had previously done my own surgery by shutting down processes and services and tweaking other Windows functions but Fidelizer sounds better to me and, frankly, the computer runs smoother this way (extremist mode with networking). I don’t use my server for anything else other than music btw, and I run Win 8.1. Eventually I will try Win Server 2012/JPLAY/AO but I am concentrating on hardware at the moment. What matters the most is hard to say. It all adds up and in many, many ways it would be much easier, and probably cheaper in the long run, to go with a commercial product. But it’s not just a hobby, right? It’s an obsession…
Sorry that this is a lot of vague stuff. The details are pretty daunting, especially if futzing with computers is not your thing. My point is that the computer end of things makes more than a little difference in your sound and is definitely worth pursuing.