Frequency range
The range of audio frequencies reproduced by the subwoofer. As a general rule, the wider the frequency range, the richer the sound and the more detail the speaker can convey. However, it is worth remembering that subwoofers as a class are designed for low and ultra-low frequencies in the range from 20 to 150 (sometimes 200) Hz. Therefore, in fact, a significant difference in sound is noticeable only with a large difference in the reproducible ranges (for example, 20-200 Hz and 50-150 Hz).
Also, do not forget that an extensive frequency range is not yet a guarantee of high-quality sound; and in some cases (for example, if the main speakers of the speaker also cope well with low frequencies), it may be completely redundant.
Speaker size
The diameter of the speaker(s) installed in the subwoofer.
It is believed that the larger the speaker (
15 ",
18 " or more), the more power it can produce and the deeper the bass sound on such acoustics. However, in modern subwoofers, manufacturers use various tricks to achieve good sound depth even with relatively small speaker sizes (
10 ",
8 "). Therefore, it is possible to unambiguously compare different models only if they differ significantly in this indicator; and even then in such cases it is worth paying attention not so much to the diameter of the speaker, but to the price category. The golden mean among sizes are
12-inch subwoofers.