Over a year after it began, the whole-house-audio project is complete. 4 rooms around the house can now be filled with the sound of any of (currently) 4 audio devices thanks to a mixture of hardware and software.
One thing that has been lacking since the first build of the rack is ventilation. With both sets of doors closed, the inside can get quite warm, especially when iron is turned on. Not any more though, having just completed the installation of 2 active ventilation zones, lighting and a low voltage power supply system complete with rack-mount control panel.
The audio system that I’m building requires 2 low-power computers: 1 for the touchscreen controller (not using an iPod Touch for the moment) and 1 to act as a webserver and serial-console server.
Once again eBay has come to the rescue, and by searching for ‘geode’ – a low-power processor for Thin Clients & Small Form Factor (SFF) PCs – I found the 2 machines that I needed. These are the specs:
magnesium (the black one)
- 800 MHz Geode
- 256 MB RAM
- 6 GB CF drive
- Onboard graphics, audio, serial, parallel, USB & 10/100 ethernet
£70 + P&P
potassium (the grey one)
- 300 MHz Geode
- 256 MB RAM
- 6 GB 2.5″ IDE drive
- Onboard graphics, audio, serial x2, parallel, USB & 10/100 ethernet
£35 + P&P
I’ve finally gotten around to fixing the top to the rack cabinet. It’s made from the door of an old storage-only cabinet, which was actually a fridge/freezer cabinet from Ikea. The top has been cut into the correct proportions for a while, but has just sat cluttering my floor until now.
To allow the many cables to enter the cabinet a notch of approx 8cm square was cut out of one of the panels. These two panels could then be slid together without the need to disconnect any cabling already in place.
Unfortunately I’ve discovered that the top of the cabinet isn’t exactly square – it’s slightly warped, as the photo below shows when the top had been fixed. I’m not happy with this so at some point I’ll have to put some effort into correcting it. Next time I build a rack I’ll make the top and bottom in more of a similar manner, with a known square-angled piece on which to fit the timber supports.
The top currently has no ventilation, but that will change soon thanks to a lovely huge ‘Big Boy’ fan.
As part of the Whole-House-Audio system I’m building I’ve been forced to install Windows on one of the thin-clients (more details soon). I started off with Windows 98, but found that it doesn’t support USB optical drives – the thin PC doesn’t have any removable media drives – then tried Windows 2000. Everything started off fine, got past the partitioning part and onto copying the initial files. I went downstairs for a few minutes and on my return I noticed that the installer had stalled and the drive was making an odd noise. Thinking that the disc may have just become dislodged I ejected the drive to find the fragments shown above.
The genuine Windows 2000 CD, made back when MS first started off making the cool shiny holographic CDs, had completely disintegrated in the drive. There were no obvious defects when it was inserted, so I can only surmise that the discs weren’t manufacturered with todays high-speed drives in mind.
The USB DVD-Writer was new, having only unwrapped it a few hours earlier. There’s no way that an exploding CD would be covered under warranty, so I chose to attempt to fix the problem. Dismantling the enclosure and drive was harder than I thought, but I learned a lot about the good build quality of them in the process.
After removing the large shards by hand and using an air duster (outside) to remove the tiny fragments, I reassembled the drive. Fortunately it seems to work, at least the reading part does. The writing part caused errors when I tried it on one machine, but that could just be down to that machine. Since I now had no working Windows 2000 CD I ended up installing XP SP2.
Coincidentally a few days earlier I had Stumbled across an article discussing an experiment to find out the fastest that optical media could be spun before disintegrating, with some quite scary findings about just how much damage the resulting shards can do. I can’t find that article, but here’s something a little less scientific-looking.
The weak-signal problem with the MythTV PVR downstairs has been mostly resolved by replacing the coax cable between the computer and the booster by a wider diameter hand-made one. This has helped greatly with improving the signal although it’s not completely perfect. About 80% of recordings now succeed and are watchable. The remaining failures are bearable. The plan to move to satellite has hence been put on hold until things get worse.