<s>
The	O
American	O
D-22	O
and	O
American	O
D-33	O
microphones	B-Application
are	O
dual-impedance	O
,	O
omnidirectional	O
,	O
dynamic	O
microphones	B-Application
made	O
by	O
the	O
American	O
Microphone	B-Application
Company	O
.	O
</s>
<s>
The	O
D-22	O
and	O
D-33	O
were	O
introduced	O
as	O
part	O
of	O
the	O
full-vision	O
(	O
FV	O
)	O
series	O
of	O
microphones	B-Application
in	O
the	O
early	O
1950s	O
.	O
</s>
<s>
Other	O
microphones	B-Application
were	O
typically	O
large	O
and	O
bulky	O
.	O
</s>
<s>
The	O
D-22	O
and	O
D-33	O
were	O
dual-impedance	O
microphones	B-Application
with	O
the	O
high	O
or	O
low	O
impedance	O
selected	O
using	O
an	O
innovative	O
"	O
linkage	O
bar	O
"	O
under	O
the	O
name	O
plate	O
and	O
a	O
unique	O
"	O
slide-lock	O
"	O
microphone	B-Application
stand	O
mount	O
.	O
</s>
