Akai FORCE User Manual page 251

LFO LFO is an acronym for low-frequency oscillator. The LFO generates a periodic oscillation at a
low frequency and features variable waveshapes. Similar to an envelope, an LFO can be used to
modulate a sound-shaping component.
MIDI MIDI stands for musical instrument digital interface. Developed in the early 1980s, MIDI
enables interaction between various types of electronic music instruments from different
manufacturers. At the time a communications standard for heterogeneous devices did not exist,
so MIDI was a significant advance. It made it possible to link various devices with one another
through simple, standardized connectors.
Essentially, this is how MIDI works: One sender is connected to one or several receivers. For
instance, if you want to use a computer to play a MIDI synthesizer, the computer is the sender
and the synthesizer acts as the receiver. With a few exceptions, the majority of MIDI devices are
equipped with two or three ports for this purpose: MIDI In, MIDI Out and in some cases MIDI
Thru. The sender transfers data to the receiver via the MIDI Out jack. Data are sent via a cable to
the receiver's MIDI In jack.
MIDI Thru has a special function. It allows the sender to transmit to several receivers. It routes
the incoming signal to the next device without modifying it. Another device is simply connected
to this jack, thus creating a chain through which the sender can address a number of receivers.
Of course, it is desirable for the sender to be able to address each device individually. To
achieve this, a MIDI channel message is sent with each MIDI event.
MIDI Channel This is a very important element of most messages. A receiver can only respond to incoming
messages if its receive channel is set to the same channel as the one the sender is using to
transmit data. Subsequently, the sender can address specific receivers individually. MIDI
Channels 1–16 are available for this purpose.
The MIDI clock message transmits real-time tempo information to synchronize processes among
MIDI Clock
several connected devices (e.g., a sound generator's delay time to a MIDI sequencer).
Modulation A modulation influences or changes a sound-shaping component via a modulation source.
Modulation sources include envelopes, LFOs or MIDI messages. The modulation destination is a
sound-shaping component such as a filter or a VCA.
This is the most important MIDI message. It determines the pitch and velocity of a generated
Note On & Note
Off note. A note-on message will start a note. Its pitch is derived from the note number, which can
range from 0 to 127. The velocity ranges from 1 to 127. A velocity value of 0 is equivalent to a
note-off message.
Normalize Normalization is a function to raise the level of a sample to its maximum (0 dB) without causing
distortion. This function automatically searches a sample for its maximum level and
consequently raises the entire sample's level until the previously determined maximum level
reaches 0 dB. In general, this results in a higher overall volume of the sample.
Panning The process or the result of changing a signal's position within the stereo panorama.
Pitch-Bend Pitch-bend is a MIDI message. Although pitch-bend messages are similar in function to control
change messages, they are a distinct type of message. The resolution of a pitch-bend message
is substantially higher than that of a conventional controller message. The human ear is
exceptionally sensitive to deviations in pitch, so the higher resolution is used because it relays
pitch-bend information more accurately.
Program Change These are MIDI messages that select sound programs. Programs 1–128 can be changed via
program change messages.
Release An
value after a trigger is terminated. The release phase begins immediately after the trigger is
terminated, regardless of the envelope's current status. For instance, the release phase may be
initiated during the attack phase.
envelope parameter. This term describes the descent rate of an envelope to its minimum
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