Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

NAS bash

I do not use a NAS in my setup and there are several reasons why, but before I do a NAS bash, let’s examine some of the upsides of the device.

In yesterday’s post I described a summary of what differentiates NAS from other storage schemes and of those differences, perhaps the two most significant are isolation and isolation.
I guess we’ll start with isolation…

NAS have no direct connection with computers. Instead, they connect through isolated wires or the air. This is different than two other types of storage, internal and USB. Internal and USB connect directly to the computer and unless care is taken in its design – and it rarely is – power supply, ground issues and data routing can reduce sound quality. Using a NAS obviates these issues: there are no common grounds, power supplies are isolated, data routing is less intrusive. +1 for the NAS.

Isolation, two. NAS do not have to be physically close to computers. They can be one foot away or across the world with no difference in sound quality. They can also be shared by many computers. And if physical proximity is important, or sharing is advantageous, then NAS have a place in your system. +2 for the NAS.

Still I don’t use them unless there’s a good reason. Here at PS Audio we have a huge NAS run by engineering. It’s valuable as a research tool, working on the Bridge, providing identical music for multiple devices under test or use. But when I want to just listen to music, or audition a new amplifier, preamplifier, firmware upgrade for a DAC, I rely instead on a USB hard drive or the PerfectWave Memory player.

Why? NAS are slow, NAS connect through circuitous routes, NAS are painful to copy and backup, NAS are expensive, NAS requires a switch or router, NAS provides no advantage to me and I do not share my music.

Tomorrow I’ll tell you what I do and why.

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

Finishing up

Finishing up our chain of events to play music from a NAS based on UPnP (Universal Plug and Play) protocols, we discovered the controller displays the library contents sitting in the NAS, which is a network connected hard drive.

Let’s imagine we picked the track Layla, by Eric Clapton. That track is actually nothing more than a group of recorded bits on a hard drive. What distinguishes those bits from other groups of bits is an address; a memory location.

When you touch play on the controller, the track’s address information (where it lives) is sent to the player and told to connect. Once connected the bits are streamed over the network to the player, converted (in the player) to an acceptable format and reach the DAC for rendering. During this process the controller is no longer involved – you can turn it off or do whatever you wish – the only two elements involved are the NAS and the player.

So, what have we learned from a brief understanding of a NAS? Well, tomorrow we’ll cover the upside and downside of connecting with a NAS, but to close for today, let’s review:

• A NAS is a hard drive with a computer attached to it
• NAS only connects over the home’s network
• NAS do not have players built in
• NAS can connect to desktop computers, or embedded computers, but they require a controller and player to play music stored on them

NAS nearly always use a type of protocol known as UPnP to discover and connect to them

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

Yes, master!

Inside every NAS is a computer, and computers need operating systems and programs to run. The program we as music lovers are interested in is called a server, and it does what its name implies. I’ll explain its purpose but first let’s step back and look at our music system as a whole (rather than a hole, where everything falls into and nothing works, as often happens in computer audio).

There are three main elements in a music server system: controller, server, player. These three elements can be enclosed in one hardware device or broken apart into separates; their function and purpose remain the same. The controller is the human interface, the part you see and work with. The server is like the library, taking in and loaning out musical selections stored there. The player sits alone, spoken to occasionally by the server, rarely the controller, but it’s the bit we listen to – its importance cannot be overstated.

If you have ever picked up an iPad, or mobile device displaying contents of a music library, you’ve seen a controller. Controllers are pretty dumb and have little power over the system. They display artwork or lists of music stored on a computer or NAS. They seem to users like the brains of the operation, but in reality, they are simple slaves, the dumbest of all three elements in a music server. When I open Apple’s Remote app on my iPad to access music stored on my computer, I am presented with a dazzling list of album covers from which to choose. It looks very powerful indeed. But behind the scenes, little has taken place, it is the server doing the heavy lifting.

The server program on your computer or NAS receives a request from the controller. “Send me the contents of your library.” A list of tracks or group of images is forwarded from the server to the controller and displayed. When I touch an album cover the controller sends another request to the server. “Send me contents of Steely Dan,” and a text list is forwarded, the controller displays it dutifully.

If I choose the track “Aja” something entirely different happens, the subject of tomorrow’s post.

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

Mr. Rogers

Networks are like neighborhoods, each has an address where devices live. Mr. Rogers would be pleased to see things so orderly. If you have a computer, a NAS, a network attached DAC, a router, anything on the network, it too has an address that identifies it, like a house and street number. If you want to communicate with the device all you need to know is its address and you’re in (as long as you know the door code).

But what if you don’t know the address of a device you want to find? You can search for it on a computer and, if it wants to be found, it isn’t too hard. In computer speak this process is referred to as discovery and most network devices want to be discovered. Entertainment based devices on networks typically use a discovery and advertising protocol known as UPnP (also called DLNA after the organization).

Universal Plug and Play has a long history of being both a godsend and a nightmare for programmers. In its best light, it permits the ability to plug a device into any home network and communicate automatically with any other compatible device present; for example, a NAS. In theory, plug a NAS into a network and devices that may wish to access music on that NAS can now connect with no further setup. It doesn’t always work so smoothly, but it’s getting better.

The focus of these articles is understanding how NAS connect to DACs and what it all means. So, without further ado, let’s take a look at the ways we can communicate and stream music from a NAS, attached to a network.

As earlier described a NAS is a hard drive with a dedicated, built in, computer controlling it. To access data on the NAS you need another computer. This second computer can be a laptop, desktop, built into a router, built into a DAC. It’s important to note that regardless of how it’s packaged, the computer in a NAS needs another computer to speak to it as well.

So, let’s imagine we have our desktop PC and it too is attached to our home network through a router, as is our NAS.

To access music on the NAS, we open a discovery program like Finder in Mac or Explorer in Windows and look for the device.

Perhaps it’s called Paul’s NAS. Voila! There it is. What’s the first thing I want to do when connected to Paul’s NAS? See what’s inside.

That’s the job of a program on the NAS called a server. That’s where we’ll pickup tomorrow.

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

Double edged swords

NAS as storage devices sound pretty perfect from several standpoints, chief among them is isolation. They are not physically attached to a computer, like an external USB drive. Instead, they are isolated by the network cables or WIFI signals that connect them to computers sharing their services. This is a good thing because, as we know, physically connecting drives adds problems to sound. Power supply noises and ground issues are not benign to sound.

NAS have other advantages. Because they have computers built in, they need nothing more to connect to DACs in the right circumstances. For example, in our ecosystem, you can use the network Bridge to connect a NAS over the home network without another computer in the mix. In other manufacturer’s implementations this can also be accomplished with or without another computer.

But NAS are not the be all to end all that we might think. They have “issues” – issues that, like so many things in technology are both strengths and weakness. Let’s start with the first of those double edged swords, a 4-letter acronym of your choice: DLNA and/or UPnP.

NAS use a type of discovery protocol known as DLNA (Digital Living Network Alliance) or UPnP (Universal Plug and Play – though sometimes Play is comically substituted with the word Pray).

This complex system is how most NAS announce their presence on the network, as well as find other like minded machines. We’ll look to see what this means tomorrow.

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

Doesn’t matter where you are

Now that we understand a NAS (Network Attached Storage) is a computer with an attached hard drive running Linux as an operating system, the next step is to learn what it does and why it’s different than, say, a USB attached hard drive.

The simplest explanation of a NAS is found in the first letter of its acronym. It is a network device. It is connected to other devices over the LAN (Local Area Network). What does this mean? NAS connect through a router.

A router, likely the device in your home providing WIFI, also runs on the Linux operating system. Its purpose in life is that of a traffic cop: deciding where each bit of communication comes from and goes to. It’s where the internet comes into your home, your email gets sent to, and all activity of your home network is controlled.

So how is this relevant to us? NAS allow unlimited storage possibilities without regard to physical location. You could have terabytes of storage located in your basement, or if you have fast internet, on the other side of the world; accessible from any computer in the home or office. More practically speaking, NAS permit multiple computers access to the same data, and that is their core strength.

A USB attached drive connect only to a specific computer, but NAS connect to anything capable of speaking to them and it isn’t only PCs that carry conversations with NAS.

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

Linux rules the world

You would think that Windows, Microsoft’s ubiquitous operating system, is used by more computers around the world than any other, and you’d be wrong. Windows certainly dominates the desktop PC market, but when we view computers as a whole: phones, tablets, mainframes, servers, appliances, cars, and robots (yes, robots), Microsoft doesn’t hold a candle to Linux.

Linux, first released in 1991, is the most used operating system on earth. It is based on a platform called Unix, what Apple is based on. The man credited with writing Linux is Linus Torvals of Helsinki, it’s name a take off his his own.

Important to Torvals was keeping the new OS free and open. As a result Linux, the basis of Google’s omnipresent Android OS, is the most important operating system in the world. It can be said Linux runs the world. From mainframes, servers, super computers, routers, wifi, aircraft navigation systems, embedded products of all kinds, network switches, televisions, video games, spacecraft, mobile phones, watches, PCs and, relevant to our field, NAS and music servers, Linux touches everything. We hear much about Windows and Apple’s IOS, but PCs are only a fraction of the computers in use today.

Linux is popular because it’s free, but that’s only part of the story. Linux runs everything because much of the world is involved in making it better. And once you employ the world to program your product, you have far more resources than a few thousand programers in Redmond or Cupertino.

The subject of the next day’s posts is the NAS (Network Attached Storage) and Linux runs all NAS. So, when I start to write of the OS (Operating System) of a NAS, you’ll know it is Linux. Oh, and NAS connect over LANs (local Are Networks) and LANs (our home networks) run on Linux as well.

Thanks Linus, Linux is a gift that keeps on giving in a free an open world. Bravo!

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.


A NAS is a Network Attached Storage device; a computer with a hard drive. Most computers have hard drives, so what makes this different? It is dedicated to the task of finding, storing and retrieving files on its hard drive. In addition a NAS is able to announce its presence over a home network and communicate with others sharing that same connection. While its function is simple to explain, its inner working aren’t.

If we break down the major tasks NAS perform into two broad categories: file and network management, we discover each takes a tremendous amount of programming to work. It may sound simple for a computer to search a hard drive, locate files, send them somewhere or rewrite new over old, but it takes an entire operating system to do so. In fact, one of the original operating systems, Windows, was based on DOS (Disk Operating System) and its primary function was the very tasks described. Of course today’s operating systems like, Windows, Apple’s IOS, and Linux are huge compared to Bill Gates original wonder toy, but at their core that’s what they do: find, store, retrieve, access files on memory drives, both hard and soft.
Any computer can be configured as a NAS, because any computer is a NAS, and then some. But all NAS cannot be configured as more than what they are designed to do, because their programming instructions are limited. Still, they are based on a very robust operating system, typically Linux.

Linux is a free operating system and, used increasingly in consumer electronics, and it is no less robust than paid version like Windows and Mac. Tomorrow I want to spend some time talking of Linux, one of the most important operating systems in the world, one few know much about, yet this system controls much of our lives.

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

To NAS or not

That is the question and I figured it might be worth a post or two to explore. The original question posted was this: what’s the sonic difference of using a Mac Mini or a NAS as a server? It’s a very good question, asked often.

First, let’s get clear what each is, then we can go on to answering some of the more perplexing aspects. Both a NAS (Network Attached Storage) and a Mac Mini are computers. Both have hard drives, both have operating systems, both have GUIs to control them, though built in and require an external monitor, mouse and keyboard to control.

So what are the differences? The Mac Mini is a sophisticated computer with a hard drive, and a NAS is a hard drive with an unsophisticated computer. Think of them this way: Mac Mini is a computer first, hard drive second, and a NAS is the opposite.
One of the major differences between the two is how they connect to our DACs, though the Mini is a bit of a chameleon and can go both ways, while a NAS cannot.

Tomorrow let’s start with understanding the NAS.

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

Too much salt

Some stereo systems are so accurate they’re sterile. Others are so euphonic they drip of syrup. And aren’t we all after accurately reproduced, emotionally involving music? I believe it is possible to have both, but attaining that lofty goal remains elusive for many.

One of our customers just emailed me and suggested their system “lacked warmth” and hoped our DAC would fix the problem. And perhaps it would, but I cautioned the person to step back and think deeply of the problem.

If a prepared dish is too salty, one trick cooks use is to add potatoes to absorb excess salt. While this is effective, in the same way as adding a different piece of gear to add or subtract warmth, it is best to use less salt in the first place.

Before jumping to the next tweak to fix what your system lacks, sometimes it’s better to rethink the chain itself.