<s>
A	O
double	B-Architecture
bass	I-Architecture
array	I-Architecture
(	O
DBA	O
)	O
is	O
a	O
specific	O
layout	O
of	O
subwoofers	B-Application
within	O
a	O
rectangular	O
listening	O
space	O
.	O
</s>
<s>
A	O
DBA	O
requires	O
at	O
least	O
two	O
subwoofers	B-Application
(	O
preferably	O
same	O
make	O
and	O
model	O
)	O
that	O
are	O
placed	O
at	O
opposing	O
walls	O
in	O
a	O
specific	O
layout	O
.	O
</s>
<s>
The	O
signal	O
played	O
by	O
the	O
subwoofer	B-Application
array	O
on	O
the	O
back	O
wall	O
is	O
inverted	O
and	O
delayed	O
based	O
on	O
the	O
distance	O
to	O
the	O
frontal	O
subwoofer	B-Application
array	O
.	O
</s>
<s>
Modes	O
between	O
side	O
walls	O
,	O
floor	O
and	O
ceiling	O
are	O
suppressed	O
by	O
arranging	O
the	O
subwoofer	B-Application
in	O
a	O
specific	O
grid	O
:	O
</s>
<s>
Interference	O
of	O
the	O
subwoofers	B-Application
and	O
mirror	O
sources	O
create	O
a	O
plane	O
wave	O
up	O
to	O
a	O
certain	O
frequency	O
.	O
</s>
<s>
Due	O
to	O
the	O
specific	O
grid	O
layout	O
of	O
the	O
subwoofer	B-Application
array	O
most	O
modal	O
effects	O
are	O
suppressed	O
.	O
</s>
<s>
Most	O
active	O
subwoofers	B-Application
also	O
offer	O
a	O
polarity	O
switch	O
.	O
</s>
<s>
Subwoofers	B-Application
should	O
be	O
placed	O
as	O
close	O
as	O
possible	O
on	O
the	O
wall	O
where	O
they	O
easily	O
can	O
be	O
made	O
invisible	O
.	O
</s>
