<s>
These	O
wireless	B-Device
speaker	I-Device
systems	O
are	O
battery	O
powered	O
and	O
play	O
audio	O
over	O
a	O
wireless	O
connection	O
from	O
a	O
separate	O
source	O
device	O
(	O
such	O
as	O
a	O
computer	O
or	O
smartphone	B-Application
)	O
.	O
</s>
<s>
Most	O
models	O
use	O
Bluetooth	B-Protocol
to	O
communicate	O
with	O
the	O
source	O
device	O
.	O
</s>
<s>
The	O
first	O
SoundLink	O
product	O
was	O
released	O
in	O
2009	O
and	O
used	O
a	O
USB	B-Protocol
wireless	O
transmitter	O
plugged	O
into	O
the	O
computer	O
to	O
receive	O
audio	O
from	O
the	O
computer	O
(	O
using	O
a	O
proprietary	O
protocol	O
—	O
not	O
Bluetooth	B-Protocol
)	O
.	O
</s>
<s>
It	O
used	O
Bluetooth	B-Protocol
to	O
communicate	O
with	O
the	O
source	O
device	O
.	O
</s>
<s>
The	O
SoundLink	O
Mobile	O
was	O
replaced	O
by	O
the	O
SoundLink	O
Bluetooth	B-Protocol
Mobile	O
Speaker	O
II	O
,	O
sold	O
from	O
2012	O
until	O
2014	O
.	O
</s>
<s>
The	O
other	O
major	O
change	O
to	O
series	O
2	O
was	O
the	O
change	O
from	O
DC	O
charging	O
to	O
USB	B-Protocol
charging	O
,	O
which	O
provided	O
a	O
more	O
convenient	O
charging	O
solution	O
.	O
</s>
<s>
The	O
USB	B-Protocol
charging	O
port	O
also	O
allowed	O
the	O
user	O
to	O
install	O
software	O
updates	O
through	O
btu.bose.com	O
when	O
available	O
.	O
</s>
<s>
However	O
,	O
it	O
featured	O
a	O
better	O
battery	O
,	O
which	O
was	O
capable	O
of	O
12	O
hours	O
of	O
playtime	O
and	O
chargeable	O
in	O
4	O
hours	O
,	O
as	O
well	O
as	O
a	O
USB-C	O
port	O
.	O
</s>
<s>
The	O
SoundLink	O
Color	O
was	O
introduced	O
in	O
2015	O
as	O
Bose	O
's	O
portable	O
Bluetooth	B-Protocol
loudspeaker	O
.	O
</s>
<s>
It	O
was	O
battery-powered	O
,	O
and	O
charging	O
was	O
via	O
a	O
micro-USB	O
port	O
.	O
</s>
<s>
To	O
date	O
,	O
it	O
is	O
the	O
cheapest	O
and	O
smallest	O
Bluetooth	B-Protocol
speaker	O
offered	O
by	O
Bose	O
.	O
</s>
<s>
This	O
speaker	O
uses	O
a	O
Micro	O
USB	B-Protocol
charger	O
with	O
a	O
charging	O
cable	O
included	O
in	O
the	O
box	O
.	O
</s>
