Roland VGA-7 Musical Instrument Amplifier User Manual


 
7
Main Features
Broad Expandability
Stereo external input jacks are provided, allowing you to
mix the sound of the VGA-7 with an external sound
source, such as a guitar synthesizer. Stereo line out jacks
convenient for recording are also provided.
The foot control jack lets you use your feet to select
patches or turn effects on/off. You can also connect an
expression pedal to control volume or wah.
MIDI connectors allow VGA-7 patch changes and other
operations to be controlled from an external MIDI
device. You can also transmit VGA-7 settings to an
external MIDI device to be saved.
Sound Modeling
Roland believes that the final evaluation of an electric
guitars sound should not be based only on sound output
from the guitar itself, but should also include the sound that
passes through the guitar amps, speakers, and other
equipment.
To achieve this, its necessary to simulate all the steps along
the way from the moment a guitar string is plucked, until
the time the sound reaches the ears thereby re-creating the
sound. Roland has made it possible to re-create these steps
with this latest sound modeling technology in other
words, other means are used to make a virtual model of the
physical structures and materials that actually exist.
COSM
The new Composite Object Sound Modeling (COSM)
advanced by Roland combines a number of sound modeling
technologies to create even newer sounds.
COSM is able to combine optimized sound models for
various objects to simulate anything from existing musical
instruments to sound-producing structures that could not
physically exist in the real world.
COSM GUITAR/COSM AMPLIFIER
COSM guitar/COSM amplifier are modeling technologies
that can reproduce the sounds of any existing guitar. This
includes the following.
Electronic Modeling, which simulates all characteristics
which can be attributed to the use of vacuum tubes,
transistors, and all other electronic circuitry.
Magnetic Modeling, which simulates all the
characteristics which can be produced as a result of
using pickups, transformers, speakers, and other
electromagnetic parts.
Physical Modeling, which simulates all the
characteristics that are produced as a result of the use of
certain types of materials to make a guitar, including the
kind of wood, metal parts, or finish that are used.
In addition, COSM guitar is able to produce completely new
sounds that never existed before. The numerous harmonics
contained in the sound from the vibrating strings (the sound
source) can be radically emphasized, added to, or removed,
in order to create totally new guitar sounds.
A guitarist conveys musical expression through string
vibration. Vibrating strings carry a great deal of information
about the dynamics of a performance, including that which
expresses the way in which strings have been pressed, the
location at which theyve been picked, the position of the
pick, and the kind of vibrato that's been used. The V-Guitar
system uses the string vibration itself (which contains all of
this performance information) as the sound source, and can
create not only previously existing guitar sounds, but also
completely new sounds. One great advantage of this system
is that it preserves the playing dynamics of the guitarist, as
they are conveyed by the vibration of the string.