Korg Oasys - How Sampling Mode Is Organized; Samples and Multisamples

Sampling (Open Sampling System)
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2)Youcansampleexternalaudiosourcesviathe
OASYS’inputjacks(see“Samplingmode”1and2,
above).Atthistime,youcanmixtheOASYS’own
performancewiththeaudiosignalsfromtheexternal
sourceandsamplethecombinedresult,oryoucan
monitortheperformanceoftheOASYS
while
samplingonlytheexternalsourcefromtheinputjacks.
3)InSequencermodewhenyousampleanexternal
audiosourcethat’splayingalongwiththesong
playback,notedatawillbeautomaticallycreatedina
tracktotriggerthissampleattheappropriatemoment
inthesong.Thismeansthat
youcansampleyourvocal
orguitarperformancewhileplayingbackthe
sequencer.ThisiscalledtheIn‐TrackSampling
function.
Sampling frequency and bit resolution
Asshowninthediagram,samplingreadsthelevelof
theanalogsignalatfixedintervalsalongthetimeaxis,
andstoresthelevelsinmemoryasdigitaldata.
The“fixedintervals”mentionedabovearegenerally
expressedasthe“samplingfrequency.”48kHz
(kilohertz)meansthatsamplingisperformed48,000
times
eachsecond,andthattheintervalis1
(second)/48,000(times)=approximately0.00002083
(seconds)=approximately0.02083mS(millisecond).
Thehigherthesamplingfrequencyis,theclosertothe
originalanalogsignalthewaveforminmemorywill
be.
Eachlevelisread,andconvertedintodigitaldata.The
accuracyatthistime
isdeterminedbythebit
resolution.Thisprocessconvertsananalogsignalwith
infiniteresolutionintoadigitalsignalwithfinite
resolution.With16bitresolution,eachlevelis
indicatedin65,536steps(thesixteenthpoweroftwo).
Thegreaterthebitresolutionis,the closertothe
originalanalogsignal
thewaveforminmemorywill
be.
48kHz16bitsamplingisthesamequalityasinaudio
devicessuchasDAT.ACDuses44.1kHz16bit
sampling,whichisaslightlylowersampling
frequency.
How Sampling mode is organized
ThissectiondescribeshowsamplingontheOASYSis
organized.(Seethediagrambelow)
Samples and Multisamples
Samples
Thedatathatisrecorded(sampled)intointernal
memoryorloadedfromafileisreferredtoasasample
orsamplefile.Samplesconsistoftheactualwaveform
data,andparametersthatspecifyhowthedatawillbe
playedback,suchasStart,LoopStart,andEnd
Address.Samplescan
beusedinmultisamplesand
drumkits.
TheOASYScanholdamaximumof4,000samplesin
itsinternalmemory.
TheOASYScanshareasinglewaveformamong
multiplesamples.Thisallowsyoutocreatemultiple
sampleswithdifferentplaybackaddressesfromthe
samewaveformwithoutwastinginternalmemory.For
example,
supposethatyouhavewaveformdatathat
recordsavoicesaying“One‐Two‐Three.”Thissingle
pieceofwaveformdatacouldbesharedbythree
samples,withtheplaybackofsampleAproducing
“One‐Two‐Three,”sampleBproducing“One‐Two,”
andsampleCproducing“Two‐Three.”
Formoreinformation,see
“Copy”onpage 681ofthe
ParameterGuide.
S
ampled digital
w
aveform
Time
Level
Level
Time
A
nalog waveform
16 bit
=65,536 leve
ls
of data
48 kHz
= 48,000 times every second
= 0.0208 mS cycle
CD-R/RW Drive Audio Input
(Audio CD)
(Ripping)
ADC
Sample 0000 ... 3999
RAM (memory):
DAC
Insert Effects
(Master Effects)
Disk
Multisample 000 ... 999
AUDIO INPUT jack
Analog/digital
convertor
Analog signal
Analog signal
Digital signal
Used by combinations
and songs
Resampling
Program, combinations and
songs
AUDIO
OUTPUT
jack
RAM (internal memory)
WAVE File
Digital/analog
convertor
Analog signalDigital signal
Program
ConceptualdiagramoftheOpenSamplingSystem