bitperfect musicplayer

So it came to pass that we needed a good music source for our experiments with loudspeaker cabinets.
Tired of all these over modulated CD masters I started looking for vinyl rips.
I always loved Radiohead's, OKcomputer, but I really hated the CD production.
I actually ended up in buying 2 copies because I thought the first one was 'broken'.
Bliss came upon me when I first heard the vinyl rip some audiophile made of this same record! So..

24/96 it will be from now on!

Almost one year passed and progressive insight makes me want to  review this post. (although I actually never finished this tutorial ).
First of all, how firm is the above stated claim that one can only achieve quality audio with 24bit - 96kHz ? 

Surely, while processing audio in live or studio environment even 24 bit doesn't yield enough headroom, but once we are finished in a master I think 16 bit (as advocated by  the majority of professionals) will provided enough headroom for even the most dynamic music.
Now what about the 96k?
Everybody knows the Nyquist theorem.
So turning this around and claiming 96kHz would be mandatory would also imply a hearing that reaches into the 40kHz region, but hey, we are humans not dogs!

Now why did I bluntly and boldly put this claim on this blog?
Is there really no difference?
One year later and suddenly I am conformed to mediocrity?, you should read the 24/96 as a quality stamp!
People making in effort in using the best AD/DA converters will use 24/96 while they are at it. Why not? Bigger, cheaper storage capacity and fast internet make big files not an issue any more.

Now what is the fuzz with this 'bitperfect'?
And why is this only half the story?

Two things while processing digital audio:
First, one will loose bit depth with every alteration in the digital domain if no cunning precautions are taken .
Be it resampling or adjusting EQ or even adjusting volume. 
So audiophiles will try to preserve their precious 16 bits (24?) in their audio files by avoiding all 'suspect' software.
For us mortals the only controllable way would be by using Linux (and alsa for that manner)

Second, and mostly forgotten, property of a quality digital audio stream is the stability of the ticking of your clock (be it 44.1, 48 or 96)
Pro-audio guys and gals used to be really fond off their  Grimm clocks  before manufacturers did clean up their 'clock act'.
So also in the (domestic) reproduction of our audio streams real care must be taken in clock stability.
That's why usb is not all ways the best choice as a output port for your audio.
Also the influence of a fluctuating or noisy computer PSU on the clocks stability can be disastrous, so cards in PCI slots running on the computer PSU might not be the best option.
I found out by observing the difference in audio quality by playing back a same file from a NAS as opposed to from internal HD.


Easier said then mixer, asio drivers, core audio, itunes, minijacks..all giving me grieve and headaches.
And then we discovered Linux.
And SSH, and SAMBA, and TRANSMISSION and last but certainly not least the excellent MUSIC PLAYER (DAEMON). So here we go.:

A tutorial on how to use a crappy old computer as a dedicated music source in your home network, running headless as a server, and controlled with your smartphone/workcomputer/tablet:

What do you need:
  • crappy old computer eating dust in the corner of your cabinet 
  • decent sound card (preferably PCI, some people argue against USB interfaces)
  • Linux server edition, Ubuntu server 12.04 is a good choice
At a zillion of places on the internet people tell you how to install linux using a USB stick.
If you are not experienced with this get some practice before you proceed.
Be prepared for some keyboard commands (ahh help!) as opposed to bluntly clicking next next next with your mouse on this journey..
Remember to get a server-edition of your preferred distro and not a full blown desktop like Ubuntu12.04 or LinuxMint or OpenSuse or whatever.
That's a different play.
Come back here if you have managed to get a command prompt looking a bit like this on your screen. ;)


Since we are going to run your new musicserver without any keyboard, mouse or screen attached the next thing to do would be installing some software to approach your music-server-to-be from a different  computer/tablet/smartphone in your home network.
In Linux world we would use this nifty protocol called SSH. Don't break your head on how it works just type the next magic words after your command prompt:

sudo apt-get install ssh

After asking for your password the LinuxOS will now throw some information at you which might make no sense but just type faithfully a y for yes and if all is well you will be able to connect from a different computer in your network.
For our window friends you would need something like putty to get a terminal connection. Linux (or Mac) people: just fire up a terminal session and type:

ssh <yourusername>@musicserver.lan

It depends a bit upon  your dhcp server, but sometimes you will have to fiddle a bit and find out what ip address has been assigned to your musicserver and use this address directly so maybe you need to type something like:

ssh <yourusername>@

If you have managed to connect to your musicserver from a different computer you can now disconnect the monitor, mouse and keyboard and put them back in that cupboard eating dust again, since we are not going to use them anymore.
Next we are going to install and configure samba to get the file sharing up and going, next will be transmission to lurk all these nice flac transcripts and finally finally we will be installing and configuring MPD to get the magic happening..

<soon, to be continued..>