Better PC Sound

Posted at: Friday 29th February 2008 by Chris Lee

Just how good can PC audio be? Chris Lee investigates how to get the best audio quality from your computer, then pits the humble PC against one of the best CD players on the market.

This combination costs around £1,650, but in order to guarantee that we'd be able to pick up differences between different components, we also needed some high-quality speaker cable. Russ Andrews (www.russandrews.com) was eager to show us what we were missing out on, and provided a pair of Kimber Kable 8PR speaker cables. Compared with the cheap and nasty doorbell wire from some budget PC speakers, the Kimber Kable looked thick enough that a shark would struggle to bite through it.

The icing on the cake was a Cambridge Audio Azur 840C CD player to match the integrated amp. This CD player is, in a way, the most interesting part of the test kit, as it performs the same job as the PC when it comes to playing music - feeding the speakers by changing digital information into an analogue signal. This 840C was used as a benchmark to judge the sound quality coming from the PC.

After three days of experimenting with speaker placement, reverberation dampening (otherwise known as hanging a duvet on the lab wall) and different listening positions, we were confident that we had a setup that was capable of putting our PC through its paces. Playing a CD didn't just sound good; it had us grinning from ear to ear. There was a depth, power and warmth to the sound that we've never experienced with PC speakers, even high-end models such as the Logitech Z-5500s, and the clarity and detail were fantastic.

Next, it was the turn of our test PC. Affectionately known as 'The Labs Rocker', this is the machine that we've used for playing music in the lab for several years. Its motherboard is an Asus A8V and features AC97 audio via an ALC850 codec.

The codec's main job is to use its built-in DACs (digital-to-analogue converters) to turn one or more streams of digital audio into between two and eight channels of analogue sound, mix and amplify the signal where necessary, and output it through the ports on the motherboard. Motherboard manufacturers vary the codecs they use, selecting from a range of four or five common chips, but the HDA audio controller, which is embedded in the Southbridge, has been standard across most Intel chipsets since 2004. As such, our test PC represents the audio capabilities of many PCs.

Once the PC was up and running, we eagerly hooked up a bog-standard 3.5mm audio cable from the analogue line-out port of the motherboard to the amp and fired up iTunes, expecting to see similarly pleasing results as those of the 840C. However, in comparison with the CD player, the sound quality coming from the PC was rubbish - dull, flat and relatively difficult to listen to, with gaps in the sound. We were surprised and disappointed in equal measure. One thing's for sure - we certainly had our work cut out to make the music coming from our PC sound as good as the music coming from the hi-fi.

CD Quality