Verdict: Dolby digital encoding gets even cheaper
Creative has always had a definite plan as to how sound on the PC should work, and this vision is quite different to how audio is handled by consumer electronics. Creative's SoundBlaster X-Fi and Audigy cards include on-board Dolby Digital decoding, so even if you hook up your surround speakers using analogue connections, you can listen to surround-sound audio. By contrast, to get proper 5.1 audio from a DVD (not just an upmix) in your lounge, you need to connect your speakers digitally to a Dolby Decoder and your DVD player.
Like the HDA Digital X Mystique, the Aureon 7.1 PCI from Terratec is based on the C-Media CMI8768+ chip. While it can't perform Dolby Digital decoding, it does have a built-in Dolby Digital Live encoder, so it can take any sound source and convert it to a discrete 6-channel digital bitstream. This sort of signal is just what a Dolby Digital Decoder craves; it allows you to experience DVD-like 5.1 surround sound in music and games, as well as films. If you have the right kit, a card such as the Aureon could be a more cost-effective alternative to an expensive X-Fi.
Throwing the card in at the deep end, we tested the Aureon alongside a Creative X-Fi Xtreme Music card. The Aureon was connected via its S/PDIF port and an optical cable to our favourite Logitech Z-5500 digital speakers, which have their own Dolby Decoder.
Firstly, we tested the Aureon's music playback capability. After reading the X-Fi's box, you'd expect that its '51 million transistors' and '10,000+ MIPS' would create music so 'Xtreme' it would blow away the competition. However, the Aureon held its own. Music from an audio CD was dynamic and clear, and with the DDL encoder enabled, the droning electronic instruments of Massive Attack were given the freedom of the satellite speakers. The vocals remained bright and untouched on the centre speaker, an effect similar to what you can hear on DVD-audio discs, and certainly an enjoyable experience. The Logitech Z-5500 speakers were obviously very appreciative of the crisp, clean signal provided.
However, when it came to MP3s, the X-Fi has an advantage in the shape of its 24-bit Crystalizer, which means that it can elegantly remaster 16-bit sound files using its unusually powerful sample rate conversion engine. This meant that the X-Fi offered dynamic, punchy sound that the Aureon was unable to match. Overall, the Aureon card was better at playing music than any motherboard audio codec, but it wasn't as authoritative as the X-Fi.
Pleasantly impressed, though, we fired up some games. Due to its C-Media chip, the Aureon only supports EAX 1 and 2 spatial effects, so playing Battlefield 2 further boosted the X-Fi's ego. The Aureon offered an enjoyable experience, with good placement of sounds and loud, high-impact explosions, but the X-Fi was even better. Switching Battlefield 2 to EAX 5.0 mode made the game luxuriously immersive.
Quake 4 also sounded good on the Aureon, especially when leaving the claustrophobic corridors of the Strogg base and running into the air defence trenches. The DDL encoder helped the speakers to fill the room with incessant exploding shells and hectic gunfire. However, there were many noticeable improvements when we switched to the X-Fi, including a nice metallic echo effect in the corridors and superior dialogue. When you turned your back on characters with the Aureon, their voices remained locked to the centre speaker, but the X-Fi allowed their voices to surround you, which was much more atmospheric.
On the whole, the Aureon made good use of our surround-sound speaker system, but when we plugged analogue speakers into both cards, it lost its ability to create 5.1 surround sound, so games and films suffered. Music playback was still good, but the Aureon is really only suitable for those with a Dolby Decoder and 5.1 speakers.
This means, of course, that if you use a headset when playing games, the Aureon doesn't cater for you. The CMSS-3D pseudo-3D sound placement effects offered by the X-Fi are impressive, and the Aureon has nothing to match this, with games sounding flat when we used headphones.
The Aureon might be scrawny and budget-friendly, but it has a good array of I/O ports: both microphone and line in inputs, four analogue speaker outputs and, most importantly, S/PDIF in and out in the form of two optical S/PDIF connections. The card also has an internal MIDI port.
CONCLUSION
As with the HDA card, you need a Dolby Decoder and 5.1 speakers to get the most from the Aureon, but if you have these, and can live without the more advanced positional audio effects that EAX 4 and 5 provide, then the Aureon is a good-value proposition. In fact, if your only concern is listening to CDs or watching DVDs then it's perfect. Its small size also makes it ideal for using in a media PC housed in a SFF case. If you need a sound card that offers the best music and game audio, then you may be disappointed with the Aureon, as it's outperformed by the X-Fi.
However, the Aureon is £50 cheaper than the cheapest X-Fi and still offers sound quality well above that of motherboard audio, which makes it worthy of consideration..
