KORG M3 - Manual (Page 116)

Sampling (Open Sampling System)
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3. Digital audio signals from an audio CD in a USB
A connected USB CD-R/RW drive (commercially
available) can be sampled directly (“ripped”).
4. Samples can be processed through effects and
internally sampled again (“resampled”).
You can use either “Auto” mode which automatically
applies the specified effect processing to the sample
you specify, or “Manual” mode which lets you play the
sample manually with effects applied and resample
your performance.
5. You can view the sample waveform in the display,
and modify it using a variety of waveform editing
commands (menu commands), loop settings, time
slice, and time stretch.
Program, Combination, Sequencer modes
1. You can resample a performance that uses the
functionality (filters, effects, KARMA function,
sequencer, etc.) of each mode.
2. You can sample external audio sources via the
M3’s input jacks (see “Sampling mode” 1 and 2,
above).
At this time, you can mix the M3’s own performance
with the audio signals from the external source and
sample the combined result, or you can monitor the
performance of the M3 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 M3 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
Sampled digital
waveform
Level
Time
Level
Time
Analog waveform
16 bit
= 65,536 levels
of data
48 kHz
= 48,000 times every second
= 0.0208 mS cycle
Conceptual diagram of the Open Sampling System
AUDIO INPUT jack
CD-R/RW Drive Audio Input
(Audio CD) (Ripping)
S/P DIF IN jack
ADC
Option FireWire connector
Analog/digital
convertor
Sample 0000 ... 3999
RAM
DAC
Digital/analog
convertor
AUDIO
OUTPUT
jack
Analog signal
Analog signal
IFXs (MFXs, TFX)
Digital signal
Analog signal Digital signal
Media
RAM
Multisample 000 ... 999
Program Used by combinations
and songs
WAVE File
Resampling
Program,
combinations
and songs