Testing

Stereo

We tested the two cards in several different conditions. Our sound system of choice varied depending on how many channels we were listening to. For stereo listening we decided to use one of the best speakers available – the Sonus Faber domus speakers, coupled with a high quality Primare I21 amplifier required to power them. While this arguably improved the sound quality it still allowed us to make a fair and subjective comparison of the audio quality on both soundcards.

Compressed audio

Our first test batch was composed of 3 different MP3 tracks, each saved at 320kbps. The first track we listened to was Pink Floyd’s Terminal Frost, a song where piano, guitar and saxophone exchange roles until they all start playing together. This track was perfect for judging audio crispness and clarity. Next in line was Bach’s Suite °1, a classical cello piece. Much like the first track it allowed us to judge the sound clarity, as well as give us the chance to verify how accurate the audio was (for comparison we had the same piece recorded on a vinyl disc, which is arguably the most natural sounding storage medium). Finally we put on Metallica’s St. Anger to measure the bass levels the cards were producing.

Using no audio enhancement techniques both cards produced a crisp clean output with no discernible difference. We felt the Xonar D2 produced a warmer sound, while the Prelude 7.1 delivered a more detached, “digital” sound. Bach’s Suite °1 sounded a tad more real on the Xonar D2, bringing it close to the experience delivered by the vinyl disc we used for comparison (minus the noise).

Audio CD

Playing Pink Floyd’s "Dark side of the Moon" we were immediately surprised by how good the sound reproduction was on both cards. Again the Xonar D2 sounded more warm, with bass frequencies sounding highly natural. The Prelude 7.1 didn’t disappoint either, but we couldn’t help but notice the audio lacked a certain depth the Xonar D2 was able to reproduce. Keep in mind that all of this are completely subjective observations, so some might prefer the more clean sound of the Auzen X-Fi Prelude 7.1.

5.1 and 7.1

We used Creative’s Gigaworks S750 7.1 speakers as well as the Genius’ SW-HF5.1 5000 for our surround testing. Creative’s system was used for 7.1 testing while we used Genius’ speakers for a more natural 5.1 sound testing.

Upscaling

Both cards are capable of “up scaling” stereo and 5.1 signal to full 7.1. The Auzen Prelude 7.1 does this by simply cloning the signal to all channels and then enhancing it somewhat with Creative’s proprietary X-Fi algorithms. The Xonar D2 on the other hand used Dolby Pro Logic IIx or DTS to expand the audio to 8 channels. Unlike before the two cards delivered a noticeably different sound, with the Xonar D2 outputting a fuller, more spacious sound. It could be again argued that the Prelude 7.1’s cleaner sound is better, but out personal choice would have to be the Xonar D2 and its more natural sounding output.

DVD Video

Without DTS or Dolby enabled both sound cards sounded more or less the same when playing back our two DVD movies (in PowerDVD) – The Matrix and Star Wars: The Phantom Menace. Sounds were crisp and the surround effects were well audible. After turning DTS on for the Xonar D2 our Creative speakers truly came to life, reproducing perfect positional effects even though the signal only had 6 channels.

On the Genius 5.1 surround system both cards sounded nearly identical, with the Prelude 7.1 having slightly louder bass effects by default.