Dynaudio Car Speaker BM9S User Manual

With the phase settings you can adjust the phase relationship between the subwoofer 
and main speakers. If either subwoofer or main speaker are slightly out of phase in 
relation to the other, it can result in decreased bass output in the frequency response 
area where they overlap each other.
The phase relationship between subwoofer and satellite speakers is very dependent 
on relative distance, construction and working principles of the main speakers. The 
figure on the left shows a case whereby phase of the subwoofer and main speakers 
are incorrect in the critical overlap area, thus significantly reducing acoustic output in 
the listening room in that area.

Finding the correct phase setting:
1. Play a bass-rich track which also covers the overlap area. 
2. Toggle the Phase switch between 0° and 180°. 

Depending on the bass capabilities of the speakers, the frequency range of 
subwoofer and speakers can overlap between 50 Hz and 150 Hz. A bump or a gap in 
the frequency response and thus a lower sound quality will be experienced if the 
system is not matched properly. In addition, small speakers and low powered 
amplifiers will particularly be affected by the low frequency signals, which again has 
a negative effect on the sound quality. Therefore it makes sense to limit the bass 
range of the connected speakers (called “satellites” in this case) by a highpass filter. 
The BM9S provides three settings to achieve this:

•

Flat = no limitation

•

60 Hz = frequencies below 60 Hz are cut-off

•

80 Hz = frequencies below 80 Hz are cut-off

Setting the cut-off frequency
X Switch SAT Highpass control to needed position.

•

You can not set the phase if the subwoofer is in slave mode. In this case the phase is 
controlled by the setting of the master subwoofer.