Audio Measurements
All the cards tested provided a sufficient level of output.
The Audigy cards enable redirection of the bass or, to put it another way, filtering satellite high-pass, an interesting technology for those who do not have a speaker system with a suitable filter or for users who want to build their own system.
The frequency of the filter cut-off point can be adjusted, but it's a pity that this feature is not clearly indicated.
As for performance, Creative cards demonstrated their usual weaknesses at 44.1 kHz.
At higher frequencies, the Creative Platinum EX is clearly in the lead, followed by the two Terratec cards that have a slighter higher noise level and have a slightly worse level of overall performance. There is noticeable crosstalk, for example, that increases perceptibly at high frequencies.
The Creative Platinum comes in last because of its noticeably louder interference. This problem may have been partly due to our test configuration but it is also the result of the PC's internal connections - which are very noisy. We noticed a similar phenomenon with other cards using an internal rack.
All cards tested, however, still fall under the high-end sound card category. Rightmark testing software, for example, awarded the grades of "very good" for three of the cards and "excellent" for the Platinum EX. For average-Joe users, it would be hard to find audibly noticeable faults with any of these cards.
For an easy visual comparison between these four cards, we plotted the results in a single graph, feature by feature, for the various frequencies sampled.