DIY standalone digital audio source?

[Johnnz]

Hi all,

Just wondering if anyone here has attempted to build a HDD based stand alone audio source to complement their home audio system? Either for MP3 or lossless codec recordings?

I am keen to start my own DIY hifi system (hoping to start on some Nat.P.s next year, and a Studio 350 amp.

Will probably use a ready made CD player but am quite keen to find out if any one has suggestions for building a HDD player for MP3 files etc. I imagine using an old computer, but building an attractive cabinet for it with a small (5"?) screen to navigate the music library with. Probably like to use the digital out and use a ready made high quality DAC rather than the analogue out of the computer. Prefer to make it easy to copy new music onto the hdd via USB or Network port?
I have seen something similar to this made by Naim but obviously dont mind not having the quality of sound for the convenience of playing MP3s if I can DIY it and at least make it look good on the stereo rack! (I'm a joiner by trade).

Using an old computer seems it would be the simplest way but unless there is software out there to make things easy for me then this project wont be feasible for me since I am not a programmer.

Any advice or leads much appreciated thanks.

[acko]

Hi Johnnz,

I am planning a similar system using my ackoDAC connected to usb of PC. You may wish to follow the thread. I have currently a 6.5inch integrated panel pc with 16GB compact flash drive to hold music and even video files. Will turn this into a high end source

[Johnnz]

Is this thread your one?

Looks like an interesting project. As I said I dont have programming skills but can wield a soldering iron on kitsets and always have fun learning as I go.

Any other suggestions or leads on this kind of project are welcome...

[error401]

Most of the software to do this already exists, but you will have a bit of work ahead of you integrating it all, plus with your particular hardware. I'll give you some stuff to check out though:

First, the backend.

I propose you run a Linux-based system; you'll find lots of documentation out on the 'net, but if you're a beginner you might check out Ubuntu as an easy way to get started.

This choice of OS is partly so you can use MPD, which is sort of a music playing server. All this software does is maintain your library and provide an interface to other programs to control playback or get information - other programs interact with it to give you access to your music. This gives you all sorts of neat possibilities. You can run a web-based client for MPD and control it from any web-enabled device like iPhone. You can run an MPD client on your Windows machine and connect to your player (assuming it's on the network) and browse your library and control playback as if it were at your desktop. Control it from your Bluetooth or WiFi mobile. And all of these at the same time. I love MPD, it's very cool, see the full list of clients.

You'll also probably want lcdproc which is another daemon (server program) that will control your display. And LIRC (yet another daemon) to decode IR remote codes.

Then to wire it all up, there are several 1 2 3 mpd/LCDproc clients to control the LCD, and either a LIRC client (or 2 has a built-in LIRC client - the other option is to use irpty which comes with LIRC to send keystrokes directly to the two clients that don't have built-in lirc support) to control it from your remote. For front-panel buttons, tearing apart an old keyboard is probably easiest, but other solutions exist.

The ripping will be a bit trickier, I'm sure it's possible and relatively easy to detect a CD insertion (DBus maybe?), and the ripping part is easy with any of the many command line automated rip-/tag-/organize-ers available. Hooking these two things together shouldn't be *too* difficult, but probably requires some mild scripting.

Your other option is to forget about using this as a ripper, and just connect it to the network to either access your central music library or to copy files you rip on your PC over to it. MPD can handle detecting these and adding to your library.

Now, I haven't used any of this software for what you're trying to do, but I have used most of the software listed for other things (except for the LCD MPD clients).

[Johnnz]

Thanks for that. The link for the LCD display driver is particularly interesting. If I base a system on Ubunto, how fast a boot can be obtained from an older second hand computer? Can one cut out lots of unneccesary process to make it really quick for use exclusively for audio? I.e. remove processes devoted to video/monitor?

[wakibaki]

I think that any kind of future system should be based on solid-state memory.

Even if you're not paranoid about digital issues and jitter it seems to me that you can sidestep a lot of these problems by having a solid state system and keeping the hardware fairly simple. You can get flash cards of 64G and larger, one of these will hold a lot of audio, and they're fast enough to stream HD video.

We are messing about with Fanless PCs at work at the moment. If your skills don't stretch to designing an entire standalone flash player, perhaps you could go with one of these...

w

[error401]

As far as boot time, I'm really not sure. It's a goal for the distribution to minimize this, and my oldish laptop boots to a full GUI in about 45s from power off, so I'd guess that with the GUI turned off and unnecessary services disabled you can probably get down to 20-30s. With some in-depth tweaking you could probably get it significantly shorter than that. There's also always the option of just turning off to standby mode and basically coming back on instantly.

I agree with wakibaki, though my approach would be a little different. I'd go with a small Flash disk to boot from, and do everything else over the network. If you're a normal user you're going to want your audio files available on your PC as well, so why keep two copies you have to maintain independently? Plus then you can cheap out and buy a $20 2GB CF card to boot from. It's even possible to not install *any* disk at all and network boot via PXE, but you'd probably need a Linux server somewhere on your network (and more experience) to get this going.

Regarding displays, you can usually pick up nice VFDs pretty cheap at surplus/eBay. There are some pretty nice looking 2x20 ones at Goldmine for $25 right now that should be well supported under any LCD driving software since they use the HD44780 command set and interface (you'll need to build/buy some hardware to connect it to your PC).

[acko]

Hi Johnnz,

Yes, that's my thread.

My scope of design is something that can complement my CD/HI-FI system. For serious listening i am not sure if PC audio can match but for me it is something the kids can play without messing up the expensive setup.

Technically, my system is standalone Window XP Embedded setup on a low power 500MHz fanless cpu with touch screen 6.5". The OS is customized to give it a non Windows look. Cpu hardware and OS is of fast boot type and i get 15-20s boot into operation from power. The OS is also "sealed" so that it won't get corrupted if you flick the switch and also child proof. I am trying different enclosures to give it a non PC look

You will need drivers like asio to bypass Windows ones to improve performance and software like Foobar to get reasonable quality. At this stage the built-in audio output is used but intend to switch to usb and external DAC.

Linux OS is a very good option and will try this in future

[dangus]

You can do a lot with DOS. There's Mpxplay which handles most audio formats, and can run in pure DOS or in a DOS window under some Win32 OS. It supports those parallel-port LCD displays.

As for what to run it on, there are (relatively) tiny all-in-one motherboards intended for industrial applications and point-of-sale terminals. A common brand is Advantech, if you're hunting on ebay. These often don't have on-board audio, but a USB sound adapter could work. Or careful wiring of an ISA sound card to adapt it to PC/104.

This isn't far off what folks were doing in the early days of car pcs... check out some very old threads at mp3car.com.


Other options:

tablet PC

old laptop

WRT54G compatible router with modified firmware (maybe)

Western Digital Media Player I don't know how usable it is without a proper display, but since it has RCA video out it could be hooked to a car LCD monitor (try a car parts swap meet, or the bargain table at a car audio dealer). (Or a digital picture frame that has video input - they exist.) Since it runs Linux, there is some hope that it could be hacked to run other player software, and the price is a relative bargain.

Omnifi home or car media players. A while back these were blown out cheap on Woot and other vendors. I don't think there is support for FLAC or APE yet, but I found a post that said the alternative firmware "Openfi" supports wav at least up to 16/44.

[wakibaki]

This Ionstar looks pretty good with bluray too...

w