<s>
Loudspeaker	B-Device
acoustics	I-Device
is	O
a	O
subfield	O
of	O
acoustical	O
engineering	O
concerned	O
with	O
the	O
reproduction	O
of	O
sound	O
and	O
the	O
parameters	O
involved	O
in	O
doing	O
so	O
in	O
actual	O
equipment	O
.	O
</s>
<s>
Designers	O
use	O
models	O
(	O
from	O
electrical	O
filter	O
theory	O
)	O
to	O
predict	O
the	O
performance	O
of	O
drive	O
units	O
in	O
different	O
enclosures	O
,	O
now	O
almost	O
always	O
based	O
on	O
the	O
work	O
of	O
A	B-Device
N	I-Device
Thiele	I-Device
and	I-Device
Richard	I-Device
Small	I-Device
.	O
</s>
<s>
Colouration	O
(	O
i.e.	O
,	O
more	O
or	O
less	O
,	O
delayed	O
resonance	B-Application
)	O
.	O
</s>
