Replay Mode Select; Important Information; 06, 07, And 08 Page 06 Start Point - Akai s900 Operator's Manual

arrow
at
"Loudness."
Use
CONTROL
to
vary loudness from
+50
above
the nominal
+00
point (louder) to
—SO
below the nominal
+00
point
(softer).
Note:
These
figures
represent
arbitrary
volume
units, not decibels.
NOMINAL
PITCH
(of
sample)
Point
arrow
at
"Norn
pitch."
Use
CONTROL
to
set the
initial
pitch
of the
sample
in
semitones.
To transpose
up,
choose a
higher
number.
To
transpose
down, choose a
lower
number.
Note:
If
you
trigger
the sound with the
PLAY
button,
a higher
number
will
produce a lower
pitch.
This
is
because
as the
sample
gets higher
in
pitch,
the
PLAY
button (which keeps
put-
ting
out the
same
note)
will
transpose the note lower
by a
corre-
spondingly
greater
amount.
FINE PITCH
Point
arrow
at
"Fine
Pitch."
Use
CONTROL
or the +,
—
,
and
number
keys
to
adjust the pitch plus or
minus
1
semitone,
in
cent (hundredth
of
a semitone) increments.
PAGE 04
1
REPLAY
MODE
SELECT
-2*
«REPLAY MODE
On« shot
(I).
Looping
(2).
Alternating
(3)
A
sample
may
be played
back
in
one
of three
ways.
Point
arrow
at
"Replay
mode" and
indicate
your choice
with a
number
key:
(1
One
shot.
Triggering the
sample
will
cause
it
to play for
the
duration
of
the sample, then
stop.
This
is
the default
setting.
(2)
Looping.
If
you
hold
down
a key, the
sample
will
play
all
the
way
through.
If
the key
is
still
held
down,
the
sample
will
play
again from beginning
to
end and keep
repeating
in
this
manner
for
as long as the
key
is
down.
Note:
The
entire
sample need
not be looped; a
portion
can be designated
for
looping,
as
set
on Pages
06, 07,
and
08.
(3)
Alternating.
If
you hold
down
a
key, the
sample
will
play
all
the
way
through.
If
the
key
is
still
held down,
the
sample
will
play again from end
to
beginning, then from beginning
to
end, from
end
to
beginning,
and so on
for
as long as the key
is
down.
Note:
The
entire
sample need
not
be
looped; a
portion
can be
designated
for
alternating looping,
as
set
on
PAGES
06, 07,
and
08.
PAGE05JTIME DIRECTION
(NORMAL/REVERSE)
-|? 5
tTIME DIRECTION
Normal
(I).
Rotrsi
(2)
Point arrow
at
"Time
Direction."
Use
a
number
key
to
enter
either:
(1
The sample plays from beginning
to
end.
(2)
The
sample plays from
end
to
beginning ("backward tape"
effect).
IMPORTANT INFORMATION ABOUT PAGES
06, 07,
and
08
Looping a sample, which creates a continuous, sustained tone
from a
short
sample,
is
an
art
and
a science.
Much
of this art in-
volves
finding the
proper loop points
and sample
length,
the
parameters adjusted on
PAGES
06, 07,
and
08.
Fig.
3
graphically
shows
a
flute
note's
amplitude envelope. Note
how
there
is
an attack
phase as the player
blows wind
into
the
flute,
where
the flute level
builds
up
to
full.
Then comes
a
sus-
tained portion
where the note stays basically the
same
until
the
decay,
where
the player
runs out
of
breath
and
the
level
goes
back
to zero.
If
we
wanted
to
play long
flute notes,
we
could sample the
lon-
gest notes
we
think
we
might need. Unfortunately,
this
uses up
lots of
memory, which
we
might
want
to
use
for
other
sounds.
One
solution
is
to
loop (continuously
repeat)
a
portion of
the
sound
to
create
a sustained tone.
This process
involves setting
a
start point,
stop
point,
and
loop length.
A sample
is
measured
not
in
seconds, but
in
samples. Therefore,
start,
stop,
and loop length are specified
in
samples.
The
Start point sets the
beginning
of
the
sample. This has two
main
uses:
•
If
you
started
sampling too
early,
or
if
sampling
was
triggered
by
noise,
you
will
probably
want
to
remove these unwanted
sounds
from the
beginning
of
the sample.
*
For special effects
(e.g.
cutting
off
the attack
of
a percussive
note).
The End
point sets the
end
of
a
sample. This
has two main
uses:
•
Set the
end
of
the loop
point.
*
Determine a
point
past
which no
more sample
is
needed.
The
remaining
part of
the
sample can be discarded, thus
freeing
up more memory.
Fig.
3
;
Sustained
Release
Attack phase
(player
runs
phase
out
of
break)
The Loop
Length
determines the loop length
in
sample
points
(so called
because
a
sample consists
of
a
finite
number
of
points along a
waveform;
these points define the waveform's
amplitude over
time).
The
loop's
beginning
point
is
the
end
of
the
sample minus
the loop
length.
Example:
In
the
flute
sound shown,
the start point
is
at
500
points,
the end
point
is
at
4673
points,
and the loop lenght
is
1
,223
points.
Holding
down
a key
will
repeat the looped
portion,
as
shown
in
Fig. 4.
However,
note that
the
flute
volume does
not stay
constant over
the duration of the
sample.
Therefore, there
is
a
"glitch"
(abrupt
level
change)
where the beginning
of
the loop splices
on
to the
end
of
the previous
loop.
Choosing
better loop points
can produce a loop without such
glitches.
Refer
to Fig. 5.