Here are the important characteristics of audio adapters:
It's important that the audio adapter support your speaker configuration. Audio adapters may support any combination of the following configurations:
|2.0–front left and right satellites|
|2.1–2.0 with a subwoofer|
|4.1–2.1 with a rear left/right satellite pair added|
|5.1–4.1 with a front center-channel speaker added|
|6.1–5.1 with a rear center-channel speaker added|
|7.1–5.1 with a side left/right satellite pair added|
|8.1–7.1 with a rear center-channel speaker added|
The range of human hearing is usually stated as 20 Hz to 20 kHz. All current audio adapters nominally support this range or close to it. However, few cards state±dB for that range, which specifies how flat the frequency response curve is. A good card may have frequency response of 20 Hz to 20 kHz at ±3 dB. A professional-level card may have frequency response of 20 Hz to 20 kHz at 1 dB down. In expensive cards may claim frequency response of 20 Hz to 20 kHz, but that range may turn out to be stated at 10 dB down or some similarly absurd number, which in effect means that actual usable frequency response may be something like 100 Hz to 10 kHz.
Signal-to-noise ratio ( S/N ratio), stated in dB, specifies the amount of signal (data) relative to noise, with higher numbers indicating better performance. A low S/N ratio translates to audible hiss. The best audio adapters have 95 dB or greater S/N for analog ...