Introduction to OASYS
As shipped from the factory, these samples will be
loaded and available at start‐up, along with the ROM
samples. This can be changed using the Global mode
Expansion Sample Setup menu command, if desired.
Some of the factory preloaded sounds require EXs1 to
be loaded. This includes some of the Programs in bank
INT‐E, and some of the Combinations in bank INT‐C.
These sounds either use EXs1 samples directly, or use
Wave Sequences or Drum Kits which in turn rely on
All of these Programs, Combinations, Wave Sequences,
and Drum Kits all have "EXs1" in their names, to
remind you that they require EXs1.
Note: If EXs1 is not loaded, these sounds won't play
EXs2 Concert Grand Piano: 464 MB
The EXs‐2 Concert Grand Piano serves up a singular,
breathtaking piano experience. Based on individually
sampled keys, true stereo imaging, four‐way velocity
switching and an additional damper layer, this piano
evokes unparalleled realism. The OASYS uses lossless
compression to fit 503 MB of data into 464 MB of RAM;
for more information, see "Lossless compression,"
Note: As shipped from the factory, EXs2 will not be
loaded at start‐up. This can be changed using the
Global mode Expansion Sample Setup menu
command, if desired.
In the factory preloaded sounds, the first few Programs
of bank USER‐A require EXs2 These Programs all have
"EXs2" in their names. For more information, see the
Voice Name List (VNL).
Note: If EXs2 is not loaded, these sounds won't play
Using ROM and EXs samples in your own sounds
To use ROM or EXs samples when making your own
sounds, set the Bank as desired in the Program MS
Select, Wave Sequence Step, or Drum Kit DS Select
fields. For more information, see:
• Program: "Bank (Multisample)," on page 50 of the
• Wave Sequence: "Bank (Multisample)," on page 728
of the Parameter Guide
• Drum Kit: "Bank," on page 732 of the Parameter
EXs1 and 2 are loaded into RAM using a lossless
compression technique. This yields a modest reduction
in size: EXs1 uses 284MB of RAM for 313MB of data,
and EXs2 uses 464MB for 503MB of data.
You'll notice that this is much milder than the dramatic
size reductions of mp3, or the PCM compression
sometimes found in other synthesizers. There is a
strong advantage over these other methods, however:
the OASYS compression is completely lossless, and
causes absolutely no degradation in audio quality.
User sampling RAM capacity
The OASYS comes with 1 GB of RAM pre‐installed,
which can be expanded up to 2 GB with a user‐
installable DIMM module. This memory is shared
between the operating system, ROM and EXs samples,
and RAM samples.
In particular, the size of the currently loaded EXs
samples trades off against the memory available for
RAM samples. The more space used by the EXs
samples, the less is available for RAM samples, as
EXs samples and available sample RAM
EXs1 ROM Expansion
EXs2 Concert Grand Piano
Note: To check the amount of sample RAM available,
see "0–1f: Free Sample Memory/Locations" on
page 630 of the Parameter Guide.
For more information, see "Sampling and RAM" on
page 123, "Installing memory" on page 1092 of the
Parameter Guide, and "Expansion Sample Setup" on
Selecting which EXs PCM data is loaded
You can change which EXs are loaded at any time, as
long as there is enough RAM to accommodate them.
The OASYS remembers which EXs you've selected,
and will automatically load them at startup. To select
which EXs are loaded:
1. Press the front‐panel GLOBAL switch to enter
2. Press the EXIT switch to go to the P0: Basic Setup
3. In the upper right of the LCD screen, press the
page menu button and choose the Expansion
Sample Setup command.
The Expansion Sample Setup dialog box will
appear. Each installed EXs will be shown, with a
check‐box next to its name; from the factory, this
includes EXs1 and EXs2.
4. Check the boxes for the EXs that you want to load,
and un‐check the boxes for the ones that you do
To load both EXs1 and EXs2 at the same time, you
must first expand the installed RAM to at least 1.5
5. Press the OK button.
Available Sample RAM
1GB installed 2GB Installed