The bass extension of FM8 in Low music and Low HT is same as that of F8. It is only at high bass extension setting, the two are different.

In the chart below, with bass extension controls set to Low Music, the response is 3 db down at 20Hz. The response is flat and extended.

FM8 features bass extension switch similar to F8, allowing users to select among 3 different modes: Low Music (Q=0.5), Low HT (with a 18db/oct rumble filter at 20hz), and High (24db L-R filter at 50hz). In the following, we plot the FR of HIGH position (also known as the midbass module position).

Integration

F8 provides a 12/24 db/oct switchable low pass filter to so that it can easily integrate with any front speakers.

Another aspect of getting a correct integration is phase alignment between the front speakers and the sub. We have written a guide on how to achieve a phase aligned subwoofer. F8 has a phase/delay adjustment knob. More

Output, extension and user preferences

The bass extension switch allows the user to customize the deep bass extension and the rumble filter to control cone excursion. For HT application, one can set the extension to Low-HT or High for higher SPL output. For music one may prefer a lower cut off such as Low-Music setting. Changing the settings can also result in a better integration with the acoustic gain of the room.