Build a mini PC with high-quality audio in mind

I’m building a mini PC designed as a source for high-quality audio.

It will be small, quiet, consume minimal power, and, crucially, be controlled without the need for an external monitor, keyboard or mouse.

PCs make great audio jukeboxes.

They have greater capacities than portables, the opportunity to choose from a wealth of encoding formats, and the potential for better sound quality, thanks to superior software and hardware options.

It’s this flexibility that keeps drawing me back to using a PC as both the storage and source for audio in my hi-fi system.

Sound quality has become a paramount concern of mine and, despite positive experiences with various streaming appliances, my best results to date have been with a PC.

For playback, I recently switched from a modified Logitech Squeezebox back to a normal PC, albeit one that’s connected to the best quality external soundcard I’ve ever heard: Benchmark’s DAC1 PRE.

The DAC1 PRE is actually a pre-amplifier with a digital to analogue converter and headphone amplifier, but one of its digital inputs is a USB port, allowing it to act as an external soundcard.

The results are fantastic.

Costing from £1,400 from online dealers, it isn’t cheap as a soundcard alone, but considering everything else it does and the quality delivered, it represents a bargain in serious hi-fi terms; see the Benchmark website and check out the latest HDR version, which now includes a remote control.

I recently tested the DAC1 PRE and commented with relief that my journey to hi-fi nirvana was complete.

But there was just one problem: I had brought a conventional PC back into my audio system.

Previously, I had been using a Logitech Squeezebox that looked great, ran silently, consumed minimal power and had an easy user interface with remote control and fluorescent display.

In contrast, the PC may have run fairly quietly, but it was far from silent and the power consumption was higher.

It was also relatively large, required a mo nitor to operate, and didn’t look like a piece of consumer electronics.

In short, my audio quality may have finally become everything I wanted, but the PC hardware behind it wasn’t.

The PC in question was my media system, which in its current guise isn’t particularly attractive, quiet or low-powered, but sits hidden in a cupboard. It’s perfect for playing video on a TV, but wasn’t ideal for this particular audio task.

What I wanted was something small, low-powered, very quiet (ideally silent), and that had both remote-control operation and a built-in display that would allow selection of music without needing a separate monitor.

Ironically, my existing Logitech Squeezebox already met all these requirements bar one: the device also needed to be a full PC running either Windows XP or Vista in order to use the Benchmark DAC1 PRE as an external USB soundcard.

So that’s why I’m assembling a quiet mini PC designed for audio playback and operation without an external monitor.

To make it interesting, I’m determined not to buy any new parts where at all possible, and instead recycle spare components from old projects.

This new build may be driven by my own specific requirements, but will work fine in any audio system as a front end, whether you intend to use an external soundcard or the PC’s own audio outputs.

Mini motherboard
Several years ago I became quite enamoured with Via’s range of Epia Mini-ITX motherboards or, more strictly speaking, platforms as they included an integrated processor and graphics chipset.

They were small, economical to run and some even had passive heatsinks on their CPUs for silent operation.

Via and the small form factor industry has since gone on to offer even smaller boards including the latest Pico-ITX models which measure from just 10x7.2cm.

The original Mini-ITX boards at 17x17cm seem relatively large in comparison, but remain much smaller than a traditional ATX or even Micro-ATX board while still offering a full-size Dimm and PCI slot.

Crucially, for my recycled project I also had one spare: an old Via M10000 model circa-2003 with a quietly cooled 1GHz C3 processor and integrated graphics.

There are, of course, newer models available; if you’re interested in these or smaller solutions visit the Mini-itx website.

For my requirements, though, the old M10000 would more than suffice and I fitted it with a 1GB stick of DDR memory, going spare following migrations to DDR-2 and DDR-3 platforms.

For storage, I originally hoped for a budget solid-state solution, such as booting from a Compact Flash card.

This would have been small, silent and low-powered, but one of the requirements for this particular project was a full installation of XP or Vista for compatibility with the Benchmark DAC1 PRE.

Sadly, the constant disk-hammering of both operating systems isn’t particularly friendly to Flash memory cards, and using a modern SSD would have blown the budget and broken my recycling rule.

I’m planning to experiment with a Compact Flash-based Linux installation in the future, but for now it had to be Windows XP running from a hard disk.

Not just any old hard disk though: I still had a 12GB 2.5in drive going spare after swapping it out for a 40GB model during a laptop upgrade in 2003.

This drive would not only be small and quiet, but sufficiently low-powered to allow a neat power supply ­ and as for its limited capacity, I would access the bulk of my music collection over a network.

Mini power supply
In May 2006, I tested the Pico-PSU, the world’s smallest snap-in DC-DC ATX PC power supply.

No bigger than a pair of AA batteries, the Pico-PSU slots into the motherboard’s power supply connector.

Leads emerge to power various drives, along with one that connects to an external AC adapter brick.

Then I found the Pico-PSU was happy to power a Via Epia board, a full-sized 3.5in hard disk and a laptop-style slimline optical drive, although anything hungrier could push it too far.

Since my new system only used a 2.5in laptop hard disk though, with a slimline optical drive temporarily fitted for the initial Windows installation, it was well within the specification.

Pico-PSUs and matching AC adapters are available from £35 and £19 respectively, with the latest models supporting Sata drives and four-pin supplemental connectors ­ but again be careful about choosing a supply and AC adapter to meet your requirements.

Display and remote
One of the requirements of this project was for it to be entirely operated by remote control.

The first step to achieve this was having a built-in display.

I found a Matrix Orbital MX630 USB model.

This 20x2 character display uses Polymer Light Emitting Diode (PLED) technology, which delivers similar-looking output to a VFD but with much lower power consumption and wide viewing angles.

Matrix Orbital supplies its displays with the LCDC utility to drive them from Windows, and this includes a plug-in to support Winamp; the existing WA2 plug-in also works with the latest 5.x versions of Winamp.

You can browse Matrix Orbital’s latest screens at the Matrix website.

Winamp can be configured to work with almost any remote control using a vast array of plug-ins.

I’m evaluating a variety from an old serial IR-Man to a more recent USB Windows MCE remote; if you’ve had particular success ­ or lack of ­ with certain models, we would love to hear from you.

End of story?
As I iron out the bugs, there’s only one major aspect remaining: the case.

The prime candidate is an existing Morex Cubid with a modified front panel to accommodate the Matrix Orbital screen, but this is one area where I may buy a new case ­ the Mini-ITX store has several from around £40.

While not quite totally complete, this system has been one of my most satisfying projects to date due to its entire construction (so far) from old spare parts.

While writing this column I was surprised to find many of them were up to six years old and it feels great to give them another outing.

If you have been building and upgrading PCs for some time, you’ll almost certainly have a collection of old parts that could be recycled for a system like this.