Is a subwoofer better active or passive, and should it be 10" or not?

Active is good.

For example, most of the speakers used on the computer are active speakers, that is to say, directly connected to the computer's sound card, you can use. And do not need to pass through a specialized power amplifier. The disadvantage of course is that the circuitry inside may cause some *** vibration, electromagnetic interference and so on.

It depends mainly on the frequency, but also with the intensity of the sound. The human ear reacts to a high frequency sound with a high pitch and a low frequency sound with a low pitch.

The change in pitch with frequency (Hz) is basically logarithmic. Different instruments play the same frequency notes, although the timbre is different, but their pitch is the same, that is, the fundamental frequency of the sound is the same.

The passive speaker has no internal power amplifier circuit, and requires an external power amplifier to work. It can also be seen as a "wooden box + speaker", the advantage is that the sound can reach the best state, will not be disturbed.

And the independent sound card is a special sound requirements will be targeted to buy, or more high-end with hardware-level debugging capabilities.

Active speakers as long as the correct connection to the audio cable, data lines, connected to the power supply can be used, and for the average user, listening to music and watching movies with active speakers can be completely.