Manual

206
Filter
A
filter is a component that allows some of a signal’s frequencies to pass through it and dampens
other frequencies. The most important aspect of a filter is the filter cutoff frequency. Filters generally
come in four categories: low-pass, high-pass, band-pass, and band-stop. These are the available
filters in MPC Live:
A low-pass filter (the most common type) dampens all frequencies above the cutoff frequency.
A high-pass filter in turn dampens the frequencies below the cutoff.
A band-pass filter allows only those frequencies around the cutoff frequency to pass. All others
are dampened.
A band-stop filter does the opposite of a band-pass: it dampens only the frequencies around the
cutoff frequency.
A band-boost filter boosts the frequencies around the cutoff frequency, similar to what a band on
an equalizer would do. All other frequencies pass through normally.
The number of poles in a filter’s “slope” determines how extreme or subtle the effect of the filter
will be. Filters with one or two poles produce a more subtle sound while filters with six or eight
poles are much more pronounced.
In MPC Live, the Model filters are analog-style emulations of famous vintage synth filters. Model1
is a four-pole filter that distorts at high input levels. Model2 uses a mellow resonance with a
“fattening” distortion in the lower frequencies. Model3 can produce howling, piercing resonances
and extreme sub frequencies—watch your speakers!
In MPC Live, the Vocal filters are formant filters that emulate the human voice. Vocal1 produces
“ah” and “ooh” vowel sounds. Vocal2 uses three bands to produce “oh” and “ee” vowel sounds.
Vocal3 uses five bands to emulate an idealized model of the vocal tract.
In MPC Live, MPC3000 LPF is a dynamic, resonant low-pass filter (12 dB/oct) that was used on
the original MPC3000, released in 1994.
Please also see the entry for Resonance, an essential characteristic of a filter’s sound.
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
j
ack, 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.
MIDI Cloc
k
The MIDI clock message transmits real-time tempo information to synchronize processes among
several connected devices (e.g., a sound generator’s delay time to a MIDI sequencer).