<s>
The	O
Compact	B-Device
Cassette	I-Device
,	O
also	O
commonly	O
called	O
a	O
cassette	B-Device
tape	I-Device
,	O
audio	B-Device
cassette	I-Device
,	O
or	O
simply	O
tape	O
or	O
cassette	O
,	O
is	O
an	O
analog	O
magnetic	O
tape	O
recording	O
format	O
for	O
audio	O
recording	O
and	O
playback	O
.	O
</s>
<s>
Invented	O
by	O
Lou	O
Ottens	O
and	O
his	O
team	O
at	O
the	O
Dutch	O
company	O
Philips	O
in	O
1963	O
,	O
Compact	B-Device
Cassettes	I-Device
come	O
in	O
two	O
forms	O
,	O
either	O
containing	O
content	O
as	O
a	O
prerecorded	O
cassette	O
(	O
Musicassette	B-Device
)	O
,	O
or	O
as	O
a	O
fully	O
recordable	O
"	O
blank	O
"	O
cassette	O
.	O
</s>
<s>
Although	O
other	O
tape	B-Device
cassette	I-Device
formats	O
have	O
also	O
existed	O
—	O
for	O
example	O
the	O
Microcassette	O
—	O
the	O
generic	O
term	O
cassette	B-Device
tape	I-Device
is	O
normally	O
used	O
to	O
refer	O
to	O
the	O
Compact	B-Device
Cassette	I-Device
because	O
of	O
its	O
ubiquity	O
.	O
</s>
<s>
Its	O
uses	O
have	O
ranged	O
from	O
portable	O
audio	O
to	O
home	O
recording	O
to	O
data	O
storage	O
for	O
early	O
microcomputers	B-Architecture
;	O
the	O
Compact	B-Device
Cassette	I-Device
technology	O
was	O
originally	O
designed	O
for	O
dictation	O
machines	O
,	O
but	O
improvements	O
in	O
fidelity	O
led	O
to	O
it	O
supplanting	O
the	O
stereo	O
8-track	O
cartridge	O
and	O
reel-to-reel	O
tape	O
recording	O
in	O
most	O
non-professional	O
audio	O
applications	O
by	O
the	O
mid-1970s	O
.	O
</s>
<s>
Compact	B-Device
Cassette	I-Device
tapes	I-Device
remain	O
in	O
production	O
and	O
survive	O
as	O
a	O
niche	O
format	O
,	O
continuing	O
to	O
receive	O
some	O
new	O
music	O
releases	O
.	O
</s>
<s>
Compact	B-Device
Cassettes	I-Device
contain	O
two	O
miniature	O
spools	O
,	O
between	O
which	O
the	O
magnetically	O
coated	O
,	O
polyester-type	O
plastic	O
film	O
(	O
magnetic	O
tape	O
)	O
is	O
passed	O
and	O
wound	O
.	O
</s>
<s>
Two	O
stereo	O
pairs	O
of	O
tracks	O
(	O
four	O
total	O
)	O
or	O
two	O
monaural	O
audio	O
tracks	O
are	O
available	O
on	O
the	O
tape	O
;	O
one	O
stereo	O
pair	O
or	O
one	O
monophonic	O
track	B-Device
is	O
played	O
or	O
recorded	O
when	O
the	O
tape	O
is	O
moving	O
in	O
one	O
direction	O
and	O
the	O
second	O
(	O
pair	O
)	O
when	O
moving	O
in	O
the	O
other	O
direction	O
.	O
</s>
<s>
This	O
reversal	O
is	O
achieved	O
either	O
by	O
manually	O
flipping	O
the	O
cassette	O
when	O
the	O
tape	O
comes	O
to	O
an	O
end	O
,	O
or	O
by	O
the	O
reversal	O
of	O
tape	O
movement	O
,	O
known	O
as	O
"	O
auto-reverse	B-Device
"	O
,	O
when	O
the	O
mechanism	O
detects	O
that	O
the	O
tape	O
has	O
ended	O
.	O
</s>
<s>
This	O
was	O
aided	O
by	O
the	O
introduction	O
of	O
transistors	B-Application
which	O
replaced	O
the	O
bulky	O
,	O
fragile	O
,	O
and	O
costly	O
vacuum	O
tubes	O
of	O
earlier	O
designs	O
.	O
</s>
<s>
The	O
trademark	O
name	O
Compact	B-Device
Cassette	I-Device
came	O
a	O
year	O
later	O
.	O
</s>
<s>
By	O
the	O
early	O
1970s	O
the	O
compact	B-Device
cassette	I-Device
machines	O
were	O
outselling	O
other	O
types	O
of	O
tape	O
machines	O
by	O
a	O
large	O
margin	O
.	O
</s>
<s>
Philips	O
was	O
competing	O
with	O
Telefunken	O
and	O
Grundig	O
with	O
their	O
DC-International	O
format	O
in	O
a	O
race	O
to	O
establish	O
its	O
cassette	B-Device
tape	I-Device
as	O
the	O
worldwide	O
standard	O
,	O
and	O
it	O
wanted	O
support	O
from	O
Japanese	O
electronics	O
manufacturers	O
.	O
</s>
<s>
Philips	O
 '	O
Compact	B-Device
Cassette	I-Device
became	O
dominant	O
as	O
a	O
result	O
of	O
Sony	O
pressuring	O
Philips	O
to	O
license	O
the	O
format	O
to	O
them	O
free	O
of	O
charge	O
.	O
</s>
<s>
In	O
the	O
early	O
years	O
sound	O
quality	O
was	O
mediocre	O
,	O
but	O
it	O
improved	O
dramatically	O
by	O
the	O
early	O
1970s	O
when	O
it	O
caught	O
up	O
with	O
the	O
quality	O
of	O
8-track	O
tape	O
and	O
kept	O
improving	O
.	O
</s>
<s>
The	O
Compact	B-Device
Cassette	I-Device
went	O
on	O
to	O
become	O
a	O
popular	O
(	O
and	O
re-recordable	O
)	O
alternative	O
to	O
the	O
12-inch	O
vinyl	O
LP	O
during	O
the	O
late	O
1970s	O
.	O
</s>
<s>
The	O
mass	O
production	O
of	O
"	O
blank	O
"	O
(	O
not	O
yet	O
recorded	O
)	O
Compact	B-Device
Cassettes	I-Device
began	O
in	O
1964	O
in	O
Hanover	O
,	O
Germany	O
.	O
</s>
<s>
Prerecorded	O
music	B-Device
cassettes	I-Device
(	O
also	O
known	O
as	O
Music-Cassettes	B-Device
,	O
and	O
later	O
just	O
Musicassettes	B-Device
;	O
M.C.	O
</s>
<s>
Like	O
the	O
transistor	B-Application
radio	O
in	O
the	O
1950s	O
and	O
1960s	O
,	O
the	O
portable	O
CD	O
player	O
in	O
the	O
1990s	O
,	O
and	O
the	O
MP3	O
player	O
in	O
the	O
2000s	O
,	O
the	O
Walkman	O
defined	O
the	O
portable	O
music	O
market	O
for	O
the	O
decade	O
of	O
the	O
'	O
80s	O
,	O
with	O
cassette	O
sales	O
overtaking	O
those	O
of	O
LPs	O
.	O
</s>
<s>
Another	O
barrier	O
to	O
cassettes	O
overtaking	O
vinyl	O
in	O
sales	O
was	O
shoplifting	O
;	O
compact	B-Device
cassettes	I-Device
were	O
small	O
enough	O
that	O
a	O
thief	O
could	O
easily	O
place	O
one	O
inside	O
a	O
pocket	O
and	O
walk	O
out	O
of	O
a	O
shop	O
without	O
being	O
noticed	O
.	O
</s>
<s>
Between	O
1985	O
and	O
1992	O
,	O
the	O
cassette	B-Device
tape	I-Device
was	O
the	O
most	O
popular	O
format	O
in	O
the	O
UK	O
and	O
record	O
labels	O
experimented	O
with	O
innovative	O
packaging	O
designs	O
.	O
</s>
<s>
The	O
introduction	O
of	O
the	O
cassette	O
single	O
,	O
called	O
a	O
"	O
cassingle	O
"	O
,	O
was	O
also	O
part	O
of	O
this	O
era	O
and	O
featured	O
a	O
music	O
single	O
in	O
Compact	B-Device
Cassette	I-Device
form	O
.	O
</s>
<s>
Until	O
2005	O
,	O
cassettes	O
remained	O
the	O
dominant	O
medium	O
for	O
purchasing	O
and	O
listening	O
to	O
music	O
in	O
some	O
developing	O
countries	O
,	O
but	O
compact	O
disc	O
(	O
CD	O
)	O
technology	O
had	O
superseded	O
the	O
Compact	B-Device
Cassette	I-Device
in	O
the	O
vast	O
majority	O
of	O
music	O
markets	O
throughout	O
the	O
world	O
by	O
this	O
time	O
.	O
</s>
<s>
Compact	B-Device
cassettes	I-Device
served	O
as	O
catalysts	O
for	O
social	O
change	O
.	O
</s>
<s>
One	O
of	O
the	O
most	O
famous	O
political	O
uses	O
of	O
cassette	B-Device
tapes	I-Device
was	O
the	O
dissemination	O
of	O
sermons	O
by	O
the	O
exiled	O
Ayatollah	O
Khomeini	O
throughout	O
Iran	O
before	O
the	O
1979	O
Iranian	O
Revolution	O
,	O
in	O
which	O
Khomeini	O
urged	O
the	O
overthrow	O
of	O
the	O
regime	O
of	O
the	O
Shah	O
,	O
Mohammad	O
Reza	O
Pahlavi	O
.	O
</s>
<s>
With	O
the	O
introduction	O
of	O
electronic	B-Application
skip	I-Application
protection	I-Application
it	O
became	O
possible	O
to	O
use	O
portable	O
CD	O
players	O
on	O
the	O
go	O
,	O
and	O
automotive	O
CD	O
players	O
became	O
viable	O
.	O
</s>
<s>
Sales	O
of	O
pre-recorded	O
music	B-Device
cassettes	I-Device
in	O
the	O
US	O
dropped	O
from	O
442	O
million	O
in	O
1990	O
to	O
274,000	O
by	O
2007	O
.	O
</s>
<s>
In	O
2011	O
,	O
the	B-Application
Oxford	I-Application
English	I-Application
Dictionary	I-Application
removed	O
the	O
phrase	O
"	O
cassette	O
player	O
"	O
from	O
its	O
12th	O
edition	O
Concise	O
version	O
,	O
which	O
prompted	O
some	O
media	O
sources	O
to	O
mistakenly	O
report	O
that	O
the	O
term	O
"	O
cassette	B-Device
tape	I-Device
"	O
was	O
being	O
removed	O
.	O
</s>
<s>
National	O
Audio	O
Company	O
in	O
Missouri	O
,	O
the	O
largest	O
of	O
the	O
few	O
remaining	O
manufacturers	O
of	O
audio	B-Device
cassettes	I-Device
in	O
the	O
US	O
,	O
oversaw	O
the	O
mass	O
production	O
of	O
the	O
"	O
Awesome	O
Mix	O
#1	O
"	O
cassette	O
from	O
the	O
film	O
Guardians	O
of	O
the	O
Galaxy	O
in	O
2014	O
.	O
</s>
<s>
Mulann	O
,	O
a	O
company	O
which	O
acquired	O
Pyral/RMGI	O
in	O
2015	O
and	O
originates	O
from	O
BASF	O
,	O
also	O
started	O
production	O
of	O
its	O
new	O
cassette	B-Device
tape	I-Device
stock	O
in	O
2018	O
,	O
basing	O
on	O
reel	O
tape	O
formula	O
.	O
</s>
<s>
In	O
the	O
UK	O
,	O
sales	O
of	O
cassette	B-Device
tapes	I-Device
in	O
2021	O
reached	O
its	O
highest	O
number	O
since	O
2003	O
.	O
</s>
<s>
Unlike	O
the	O
4-track	O
stereo	O
open-reel	O
format	O
,	O
the	O
two	O
stereo	O
tracks	O
of	O
each	O
side	O
lie	O
adjacent	O
to	O
each	O
other	O
,	O
rather	O
than	O
being	O
interleaved	O
with	O
the	O
tracks	O
of	O
the	O
other	O
side	O
.	O
</s>
<s>
The	O
tape	O
is	O
wide	O
,	O
with	O
each	O
mono	O
track	B-Device
wide	O
,	O
plus	O
an	O
unrecorded	O
guard	O
band	O
between	O
each	O
track	B-Device
.	O
</s>
<s>
In	O
stereo	O
,	O
each	O
track	B-Device
is	O
further	O
divided	O
into	O
a	O
left	O
and	O
a	O
right	O
channel	O
of	O
each	O
,	O
with	O
a	O
gap	O
of	O
.	O
</s>
<s>
For	O
comparison	O
,	O
the	O
typical	O
open-reel	O
-inch	O
4-track	O
consumer	O
format	O
used	O
tape	O
that	O
is	O
wide	O
,	O
each	O
track	B-Device
wide	O
,	O
and	O
running	O
at	O
either	O
twice	O
or	O
four	O
times	O
the	O
speed	O
of	O
a	O
cassette	O
.	O
</s>
<s>
Cassette	B-Device
tapes	I-Device
are	O
made	O
of	O
a	O
polyester-type	O
plastic	O
film	O
with	O
a	O
magnetic	O
coating	O
.	O
</s>
<s>
Circa	O
1970	O
,	O
3M	O
Company	O
developed	O
a	O
cobalt	B-Algorithm
volume-doping	O
process	O
combined	O
with	O
a	O
double-coating	O
technique	O
to	O
enhance	O
overall	O
tape	O
output	O
levels	O
.	O
</s>
<s>
Cobalt-adsorbed	O
iron	O
oxide	O
(	O
Avilyn	O
)	O
was	O
introduced	O
by	O
TDK	O
in	O
1974	O
and	O
proved	O
very	O
successful	O
.	O
</s>
<s>
The	O
tape	O
coating	O
on	O
most	O
cassettes	O
sold	O
today	O
as	O
either	O
"	O
normal	O
"	O
or	O
"	O
chrome	O
"	O
consists	O
of	O
ferric	O
oxide	O
and	O
cobalt	B-Algorithm
mixed	O
in	O
varying	O
ratios	O
(	O
and	O
using	O
various	O
processes	O
)	O
;	O
there	O
are	O
very	O
few	O
cassettes	O
on	O
the	O
market	O
that	O
use	O
a	O
pure	O
(	O
CrO2	O
)	O
coating	O
.	O
</s>
<s>
The	O
most	O
common	O
,	O
iron	O
oxide	O
tapes	O
(	O
defined	O
by	O
the	O
IEC	O
60094	O
standard	O
,	O
as	O
"	O
Type	O
I	O
"	O
)	O
use	O
120	O
microsecond	O
( µs	O
)	O
equalization	O
,	O
while	O
chrome	O
and	O
cobalt-adsorbed	O
tapes	O
(	O
IEC	O
Type	O
II	O
)	O
require	O
70µs	O
equalization	O
.	O
</s>
<s>
Type	O
I	O
cassettes	O
have	O
only	O
write-protect	B-Device
notches	O
,	O
Type	O
II	O
have	O
an	O
additional	O
pair	O
next	O
to	O
the	O
write	B-Device
protection	I-Device
ones	O
,	O
and	O
Type	O
IV	O
(	O
metal	O
)	O
have	O
a	O
third	O
set	O
near	O
the	O
middle	O
of	O
the	O
top	O
of	O
the	O
cassette	O
shell	O
.	O
</s>
<s>
All	O
of	O
these	O
were	O
discontinued	O
-	O
Maxell	O
simplified	O
its	O
cassette	O
offer	O
to	O
10	O
,	O
20	O
,	O
60	O
and	O
90-minute	O
lengths	O
,	O
Sony	O
exited	O
the	O
audio	B-Device
cassette	I-Device
market	O
globally	O
,	O
and	O
Imation	O
,	O
licensee	O
of	O
the	O
TDK	O
trademark	O
,	O
exited	O
the	O
consumer	O
products	O
market	O
.	O
</s>
<s>
As	O
late	O
as	O
2010	O
,	O
Thomann	O
still	O
offered	O
C10	O
,	O
C20	O
,	O
C30	O
and	O
C40	O
IEC	O
Type	O
II	O
tape	B-Device
cassettes	I-Device
for	O
use	O
with	O
4	O
-	O
and	O
8-track	O
portastudios	O
.	O
</s>
<s>
For	O
mono	O
recording	O
the	O
track	B-Device
width	O
is	O
1.5mm	O
.	O
</s>
<s>
Most	O
cassettes	O
include	O
a	O
write	B-Device
protection	I-Device
mechanism	O
to	O
prevent	O
re-recording	O
and	O
accidental	O
erasure	O
of	O
important	O
material	O
.	O
</s>
<s>
Occasionally	O
and	O
usually	O
on	O
higher-priced	O
cassettes	O
,	O
manufacturers	O
provided	O
a	O
movable	O
panel	O
that	O
could	O
be	O
used	O
to	O
enable	O
or	O
disable	O
write-protect	B-Device
on	O
tapes	O
.	O
</s>
<s>
On	O
some	O
decks	O
,	O
the	O
write-protect	B-Device
sensing	O
lever	O
can	O
be	O
manually	O
depressed	O
to	O
allow	O
recording	O
on	O
a	O
protected	O
tape	O
.	O
</s>
<s>
Extra	O
care	O
is	O
required	O
to	O
avoid	O
covering	O
the	O
additional	O
indents	O
on	O
high	O
bias	O
or	O
metal	O
bias	O
tape	B-Device
cassettes	I-Device
adjacent	O
to	O
the	O
write-protect	B-Device
tabs	O
.	O
</s>
<s>
Cassette	B-Device
tape	I-Device
users	O
would	O
also	O
use	O
spare	O
leaders	O
to	O
repair	O
broken	O
tapes	O
.	O
</s>
<s>
Home	O
computers	O
that	O
made	O
use	O
of	O
cassettes	O
as	O
a	O
more	O
affordable	O
alternative	O
to	O
floppy	B-Device
discs	I-Device
(	O
e.g.	O
</s>
<s>
Apple	B-Device
II	I-Device
,	O
Commodore	B-Device
PET	I-Device
)	O
were	O
designed	O
to	O
not	O
start	O
writing	O
or	O
reading	O
data	O
until	O
leaders	O
had	O
spooled	O
past	O
.	O
</s>
<s>
Cassette	B-Device
tape	I-Device
adapters	O
allow	O
external	O
audio	O
sources	O
to	O
be	O
played	O
back	O
from	O
any	O
tape	O
player	O
,	O
but	O
were	O
typically	O
used	O
for	O
car	O
audio	O
systems	O
.	O
</s>
<s>
An	O
attached	O
audio	O
cable	O
with	O
a	O
phone	B-Device
connector	I-Device
converts	O
the	O
electrical	O
signals	O
to	O
be	O
read	O
by	O
the	O
tape	O
head	O
,	O
while	O
mechanical	O
gears	O
simulate	O
reel	O
to	O
reel	O
movement	O
without	O
actual	O
tapes	O
when	O
driven	O
by	O
the	O
player	O
mechanism	O
.	O
</s>
<s>
Some	O
low-priced	O
and	O
pre-recorded	O
compact	B-Device
cassettes	I-Device
were	O
made	O
without	O
pulleys	O
;	O
the	O
tape	O
is	O
pulled	O
directly	O
over	O
the	O
capstan	O
drive	O
.	O
</s>
<s>
Most	O
units	O
from	O
the	O
1980s	O
onwards	O
also	O
incorporated	O
internal	O
electret	B-Algorithm
microphones	I-Algorithm
,	O
which	O
have	O
extended	O
high-frequency	O
response	O
,	O
but	O
may	O
also	O
pick	O
up	O
noises	O
from	O
the	O
recorder	O
's	O
motor	O
.	O
</s>
<s>
Later	O
models	O
would	O
adopt	O
electronic	O
buttons	O
,	O
and	O
replace	O
conventional	O
meters	O
(	O
which	O
could	O
be	O
"	O
pegged	O
"	O
when	O
overloaded	O
)	O
with	O
electronic	O
LED	O
or	O
vacuum	B-General_Concept
fluorescent	I-General_Concept
displays	I-General_Concept
,	O
with	O
level	O
controls	O
typically	O
being	O
controlled	O
by	O
either	O
rotary	O
controls	O
or	O
side-by-side	O
sliders	O
.	O
</s>
<s>
The	O
head	O
assembly	O
moved	O
by	O
actuating	O
a	O
damped	O
solenoid	B-Algorithm
movement	O
,	O
eliminating	O
all	O
belt	O
drives	O
and	O
other	O
wearing	O
parts	O
.	O
</s>
<s>
Revox	O
also	O
produced	O
amplifiers	O
,	O
a	O
very	O
expensive	O
FM	B-Device
tuner	I-Device
,	O
and	O
a	O
pickup	O
with	O
a	O
special	O
parallel-arm	O
mechanism	O
of	O
their	O
own	O
design	O
.	O
</s>
<s>
Another	O
format	O
that	O
made	O
an	O
impact	O
on	O
culture	O
in	O
the	O
1980s	O
was	O
the	O
radio-cassette	O
,	O
aka	O
the	O
"	O
boom	O
box	O
"	O
(	O
a	O
name	O
used	O
commonly	O
only	O
in	O
North	O
American	O
dialects	O
of	O
English	O
)	O
,	O
which	O
combined	O
the	O
portable	O
cassette	O
deck	O
with	O
a	O
radio	B-Device
tuner	I-Device
and	O
speakers	O
capable	O
of	O
producing	O
significant	O
sound	O
levels	O
.	O
</s>
<s>
In	O
the	O
1980s	O
,	O
a	O
high-end	O
installation	O
would	O
have	O
a	O
Dolby	O
AM/FM	O
cassette	O
deck	O
,	O
and	O
they	O
rendered	O
the	O
8-track	O
player	O
obsolete	O
in	O
car	O
installations	O
because	O
of	O
space	O
,	O
performance	O
,	O
and	O
audio	O
quality	O
.	O
</s>
<s>
Most	O
new	O
cars	O
can	O
still	O
accommodate	O
aftermarket	O
cassette	O
players	O
,	O
and	O
the	O
auxiliary	B-Device
jack	I-Device
advertised	O
for	O
MP3	O
players	O
can	O
be	O
used	O
also	O
with	O
portable	O
cassette	O
players	O
,	O
but	O
2011	O
was	O
the	O
first	O
model	O
year	O
for	O
which	O
no	O
manufacturer	O
offered	O
factory-installed	O
cassette	O
players	O
.	O
</s>
<s>
The	O
Compact	B-Device
Cassette	I-Device
originally	O
was	O
intended	O
for	O
use	O
in	O
dictation	O
machines	O
.	O
</s>
<s>
Police	O
are	O
still	O
big	O
buyers	O
of	O
cassette	B-Device
tapes	I-Device
,	O
as	O
some	O
lawyers	O
"	O
do	O
n't	O
trust	O
digital	O
technology	O
for	O
interviews	O
"	O
.	O
</s>
<s>
One	O
artifact	O
found	O
on	O
some	O
commercially	O
produced	O
music	B-Device
cassettes	I-Device
was	O
a	O
sequence	O
of	O
test	O
tones	O
,	O
called	O
SDR	O
(	O
Super	O
Dynamic	O
Range	O
,	O
also	O
called	O
XDR	O
,	O
or	O
eXtended	O
Dynamic	O
Range	O
)	O
soundburst	O
tones	O
,	O
at	O
the	O
beginning	O
and	O
end	O
of	O
the	O
tape	O
,	O
heard	O
in	O
order	O
of	O
low	O
frequency	O
to	O
high	O
.	O
</s>
<s>
The	O
key	O
advantages	O
of	O
the	O
Marantz	O
portable	O
recorders	O
were	O
the	O
accommodation	O
of	O
professional	O
microphones	O
with	O
an	O
XLR	B-Device
connector	I-Device
,	O
normal	O
and	O
double	O
tape	O
speed	O
recording	O
for	O
extended	O
frequency	O
response	O
,	O
Dolby	O
and	O
dbx	O
noise	O
reduction	O
systems	O
,	O
manual	O
or	O
automatic	O
gain	O
control	O
(	O
AGC	O
)	O
level	O
control	O
,	O
peak	O
limiter	O
,	O
multiple	O
tape	O
formulation	O
accommodation	O
,	O
microphone	O
and	O
line	O
level	O
input	O
connections	O
,	O
unbalanced	O
RCA	O
stereo	O
input	O
and	O
output	O
connections	O
,	O
live	O
or	O
tape	O
monitoring	O
,	O
VU	O
meter	O
,	O
headphone	B-Device
jack	I-Device
,	O
playback	O
pitch	O
control	O
,	O
and	O
operation	O
on	O
AC	O
power	O
or	O
batteries	O
optimized	O
for	O
long	O
duration	O
.	O
</s>
<s>
Beginning	O
in	O
1979	O
,	O
Tascam	O
introduced	O
the	O
Portastudio	O
line	O
of	O
four	O
-	O
and	O
eight-track	O
cassette	O
recorders	O
for	O
home-studio	O
use	O
.	O
</s>
<s>
In	O
the	O
simplest	O
configuration	O
,	O
rather	O
than	O
playing	O
a	O
pair	O
of	O
stereo	O
channels	O
of	O
each	O
side	O
of	O
the	O
cassette	O
,	O
the	O
typical	O
"	O
portastudio	O
"	O
used	O
a	O
four-track	O
tape	O
head	O
assembly	O
to	O
access	O
four	O
tracks	O
on	O
the	O
cassette	O
at	O
once	O
(	O
with	O
the	O
tape	O
playing	O
in	O
one	O
direction	O
)	O
.	O
</s>
<s>
Each	O
track	B-Device
could	O
be	O
recorded	O
to	O
,	O
erased	O
,	O
or	O
played	O
back	O
individually	O
,	O
allowing	O
musicians	O
to	O
overdub	O
themselves	O
and	O
create	O
simple	O
multitrack	O
recordings	O
easily	O
,	O
which	O
could	O
then	O
be	O
mixed	O
down	O
to	O
a	O
finished	O
stereo	O
version	O
on	O
an	O
external	O
machine	O
.	O
</s>
<s>
To	O
increase	O
audio	O
quality	O
in	O
these	O
recorders	O
,	O
the	O
tape	O
speed	O
sometimes	O
was	O
doubled	O
to	O
3inches	O
per	O
second	O
,	O
in	O
comparison	O
to	O
the	O
standard	O
17⁄8	O
ips	O
;	O
additionally	O
,	O
dbx	O
,	O
Dolby	O
B	O
or	O
Dolby	O
C	O
noise	O
reduction	O
provided	O
compansion	B-Algorithm
(	O
compression	O
of	O
the	O
signal	O
during	O
recording	O
with	O
equal	O
and	O
opposite	O
expansion	O
of	O
the	O
signal	O
during	O
playback	O
)	O
,	O
which	O
yields	O
increased	O
dynamic	O
range	O
by	O
lowering	O
the	O
noise	O
level	O
and	O
increasing	O
the	O
maximum	O
signal	O
level	O
before	O
distortion	O
occurs	O
.	O
</s>
<s>
Multi-track	O
cassette	O
recorders	O
with	O
built-in	O
mixer	O
and	O
signal	O
routing	O
features	O
ranged	O
from	O
easy-to-use	O
beginner	O
units	O
up	O
to	O
professional-level	O
recording	O
systems	O
.	O
</s>
<s>
Although	O
professional	O
musicians	O
typically	O
used	O
multitrack	O
cassette	O
machines	O
only	O
as	O
"	O
sketchpads	O
"	O
to	O
create	O
demo	O
recordings	O
,	O
Bruce	O
Springsteen	O
's	O
Nebraska	O
was	O
recorded	O
entirely	O
on	O
a	O
four-track	O
cassette	B-Device
tape	I-Device
.	O
</s>
<s>
The	O
Hewlett-Packard	O
HP	B-Device
9830	I-Device
was	O
one	O
of	O
the	O
first	O
desktop	O
computers	O
in	O
the	O
early	O
1970s	O
to	O
use	O
automatically	O
controlled	O
cassette	B-Device
tapes	I-Device
for	O
storage	O
.	O
</s>
<s>
Many	O
of	O
the	O
earliest	O
microcomputers	B-Architecture
implemented	O
the	O
Kansas	B-Device
City	I-Device
standard	I-Device
for	O
digital	O
data	O
storage	O
.	O
</s>
<s>
Most	O
home	O
computers	O
of	O
the	O
late	O
1970s	O
and	O
early	O
1980s	O
could	O
use	O
cassettes	O
for	O
data	O
storage	O
as	O
a	O
cheaper	O
alternative	O
to	O
floppy	B-Device
disks	I-Device
,	O
though	O
users	O
often	O
had	O
to	O
manually	O
stop	O
and	O
start	O
a	O
cassette	O
recorder	O
.	O
</s>
<s>
Even	O
the	O
first	O
version	O
of	O
the	O
IBM	B-Device
PC	I-Device
of	O
1981	O
had	O
a	O
cassette	O
port	O
and	O
a	O
command	O
in	O
its	O
ROM	B-Device
BASIC	B-Language
programming	O
language	O
to	O
use	O
it	O
.	O
</s>
<s>
However	O
,	O
IBM	B-Device
cassette	I-Device
tape	I-Device
was	O
seldom	O
used	O
,	O
as	O
by	O
1981	O
floppy	B-Device
drives	I-Device
had	O
become	O
commonplace	O
in	O
high-end	O
machines	O
.	O
</s>
<s>
Nintendo	O
's	O
Famicom	O
had	O
an	B-Device
available	I-Device
cassette	I-Device
data	I-Device
recorder	I-Device
,	O
used	O
for	O
saving	O
programs	O
created	O
with	O
the	B-Language
hardware	I-Language
's	I-Language
version	I-Language
of	I-Language
BASIC	I-Language
and	O
saving	O
progress	O
in	O
some	O
Famicom	O
games	O
.	O
</s>
<s>
Among	O
home	O
computers	O
that	O
used	O
primarily	O
data	O
cassettes	O
for	O
storage	O
in	O
the	O
late	O
1970s	O
were	O
Commodore	B-Device
PET	I-Device
(	O
early	O
models	O
of	O
which	O
had	O
a	O
cassette	O
drive	O
built-in	O
)	O
,	O
TRS-80	B-Device
and	O
Apple	B-Device
II	I-Device
,	O
until	O
the	O
introduction	O
of	O
floppy	B-Device
disk	I-Device
drives	I-Device
and	O
hard	B-Device
drives	I-Device
in	O
the	O
early	O
1980s	O
made	O
cassettes	O
virtually	O
obsolete	O
for	O
day-to-day	O
use	O
in	O
the	O
US	O
.	O
</s>
<s>
However	O
,	O
they	O
remained	O
in	O
use	O
on	O
some	O
portable	O
systems	O
such	O
as	O
the	O
TRS-80	B-Operating_System
Model	I-Operating_System
100	I-Operating_System
line	I-Operating_System
—	O
often	O
in	O
microcassette	O
form	O
—	O
until	O
the	O
early	O
1990s	O
.	O
</s>
<s>
Floppy	B-Device
disk	I-Device
storage	O
had	O
become	O
the	O
standard	O
data	O
storage	O
medium	O
in	O
the	O
United	O
States	O
by	O
the	O
mid-1980s	O
;	O
for	O
example	O
,	O
by	O
1983	O
the	O
majority	O
of	O
software	O
sold	O
by	O
Atari	B-Application
Program	I-Application
Exchange	I-Application
was	O
on	O
floppy	B-Device
.	O
</s>
<s>
Cassette	O
remained	O
more	O
popular	O
for	O
8-bit	O
computers	O
such	O
as	O
the	O
Commodore	O
64	O
,	O
ZX	B-Operating_System
Spectrum	I-Operating_System
,	O
MSX	B-Operating_System
,	O
and	O
Amstrad	B-Device
CPC	I-Device
464	I-Device
in	O
many	O
countries	O
such	O
as	O
the	O
United	O
Kingdom	O
(	O
where	O
8-bit	O
software	O
was	O
mostly	O
sold	O
on	O
cassette	O
until	O
that	O
market	O
disappeared	O
altogether	O
in	O
the	O
early	O
1990s	O
)	O
.	O
</s>
<s>
Reliability	O
of	O
cassettes	O
for	O
data	O
storage	O
is	O
inconsistent	O
,	O
with	O
many	O
users	O
recalling	O
repeated	O
attempts	O
to	O
load	O
video	O
games	O
;	O
the	O
Commodore	B-Device
Datasette	I-Device
used	O
very	O
reliable	O
,	O
but	O
slow	O
,	O
digital	O
encoding	O
.	O
</s>
<s>
The	O
use	O
of	O
better	O
modulation	B-Application
techniques	O
,	O
such	O
as	O
QPSK	O
or	O
those	O
used	O
in	O
modern	O
modems	B-Application
,	O
combined	O
with	O
the	O
improved	O
bandwidth	B-Algorithm
and	O
signal-to-noise	O
ratio	O
of	O
newer	O
cassette	B-Device
tapes	I-Device
,	O
allowed	O
much	O
greater	O
capacities	O
(	O
up	O
to	O
60	O
MB	O
)	O
and	O
data	O
transfer	O
speeds	O
of	O
10	O
to	O
17kbit/s	O
on	O
each	O
cassette	O
.	O
</s>
<s>
The	O
cassette	O
was	O
adapted	O
into	O
what	O
is	O
called	O
a	O
streamer	B-General_Concept
cassette	I-General_Concept
(	O
also	O
known	O
as	O
a	O
"	O
D/CAS	B-General_Concept
"	O
cassette	O
)	O
,	O
a	O
version	O
dedicated	O
solely	O
for	O
data	O
storage	O
,	O
and	O
used	O
chiefly	O
for	O
hard	B-Device
disk	I-Device
backups	O
and	O
other	O
types	O
of	O
data	O
.	O
</s>
<s>
Streamer	B-General_Concept
cassettes	I-General_Concept
look	O
almost	O
exactly	O
the	O
same	O
as	O
a	O
standard	O
cassette	O
,	O
with	O
the	O
exception	O
of	O
having	O
a	O
notch	O
about	O
one	O
quarter-inch	O
wide	O
and	O
deep	O
situated	O
slightly	O
off-center	O
at	O
the	O
top	O
edge	O
of	O
the	O
cassette	O
.	O
</s>
<s>
Streamer	B-General_Concept
cassettes	I-General_Concept
also	O
have	O
a	O
re-usable	O
write-protect	B-Device
tab	O
on	O
only	O
one	O
side	O
of	O
the	O
top	O
edge	O
of	O
the	O
cassette	O
,	O
with	O
the	O
other	O
side	O
of	O
the	O
top	O
edge	O
having	O
either	O
only	O
an	O
open	O
rectangular	O
hole	O
,	O
or	O
no	O
hole	O
at	O
all	O
.	O
</s>
<s>
This	O
is	O
due	O
to	O
the	O
entire	O
one-eighth	O
inch	O
width	O
of	O
the	O
tape	O
loaded	O
inside	O
being	O
used	O
by	O
a	O
streamer	B-General_Concept
cassette	I-General_Concept
drive	O
for	O
the	O
writing	O
and	O
reading	O
of	O
data	O
,	O
hence	O
only	O
one	O
side	O
of	O
the	O
cassette	O
being	O
used	O
.	O
</s>
<s>
Streamer	B-General_Concept
cassettes	I-General_Concept
can	O
hold	O
anywhere	O
from	O
250	O
kilobytes	O
to	O
600	O
megabytes	O
of	O
data	O
.	O
</s>
<s>
The	O
PXL-2000	O
was	O
a	O
camcorder	O
that	O
recorded	O
onto	O
compact	B-Device
cassettes	I-Device
.	O
</s>
<s>
Technical	O
development	O
of	O
the	O
cassette	O
effectively	O
ceased	O
when	O
digital	O
recordable	O
media	O
,	O
such	O
as	O
DAT	O
and	O
MiniDisc	O
,	O
were	O
introduced	O
in	O
the	O
late	O
1980s	O
and	O
early-to-mid	O
1990s	O
,	O
with	O
Dolby	O
S	O
recorders	O
marking	O
the	O
peak	O
of	O
Compact	B-Device
Cassette	I-Device
technology	O
.	O
</s>
<s>
In	O
1992	O
,	O
Philips	O
introduced	O
the	O
Digital	O
Compact	B-Device
Cassette	I-Device
(	O
DCC	O
)	O
,	O
a	O
tape	O
in	O
almost	O
the	O
same	O
shell	O
as	O
a	O
Compact	B-Device
Cassette	I-Device
.	O
</s>
<s>
Unlike	O
DAT	O
,	O
which	O
was	O
accepted	O
in	O
professional	O
usage	O
because	O
it	O
could	O
record	O
without	O
lossy	B-Algorithm
compression	I-Algorithm
effects	O
,	O
DCC	O
failed	O
in	O
home	O
,	O
mobile	O
and	O
professional	O
environments	O
,	O
and	O
was	O
discontinued	O
in	O
1996	O
.	O
</s>
