Burying a GS and BG series speaker/subwoofer will typically enhance the resonance of the speaker, creating an even fuller, richer sound. The deeper you bury the speaker, the larger the improvement. Please note that the level of enhancement will vary depending on the type and density of soil/dirt you are burying the speaker in. Alternatively, some users have buried the speaker in a large pot/container with dirt. While the audio performance may not be as good as burying in-ground, it will provide some sonic improvement over surface installation and an alternative way to blend in with your environment.
When burying the GS and BG series speaker, you should leave the grill at least 2" above ground level for best water and dust protection. In areas prone to flooding, you should consider installing the speaker even higher.
Burying a B series speaker would also yield some sound improvement but not as significantly as the GS and BG series. We still recommend burying the B series speaker since it helps to secure the speaker and blend in with the environment. When burying the B series speaker, you should leave approximately 1" of the bottom section exposed from ground level so the mid section can be fully exposed for proper 360° sound dispersion.