Roland VG-99 Workshop Manual page 5

Like the VG-99, a guitar synthesizer—such as Roland's GR-20—utilizes string
information from a divided pickup. However, it processes that information
in a much different way. When a string is played and sensed by the divided
pickup, the guitar synth determines the pitch of the string, and then it
converts that pitch into digital information that triggers a sound engine,
either internally in the guitar synth or externally via MIDI. As such, the guitar
is only used as an input device—like the keys on a keyboard synth—to play
sounds you call up on a menu, such as piano, strings, drums, and so forth.
With the VG-99, the guitar's string signals are the fundamental building
blocks of the sound you hear, even when the realtime modeling process
modifies that sound into something quite unlike a guitar. As a result, playing
a COSM instrument always feels and responds just as naturally as playing
your normal guitar, with every subtle, expressive nuance coming through.
Guitar to MIDI
While COSM instrument modeling itself isn't a guitar synthesizer,
the VG-99 does have the ability to use the divided pickup signal
to trigger sounds in an external synthesizer or sound module via
MIDI. This is called the "Guitar to MIDI" function, and it's basically like having
a Roland GI-20 GK-MIDI Interface built in.
Connecting a Normal Guitar Without a Divided Pickup
If you like the sound of your normal pickups as is—or you
don't want to install a divided pickup—you can still use
your guitar with the VG-99. Just plug its output into the
VG-99's rear-panel 1/4-inch GUITAR INPUT jack. You won't
be able to use COSM instrument modeling (including its alternate tunings
and polyphonic effects) or the Guitar to MIDI function; those require a
divided pickup. But you can use all the rest of the VG-99's processing options,
including COSM amps and effects.
As mentioned earlier, the Roland GK-3 and other divided pickup
systems allow you to send the guitar's normal pickup output along
with the divided pickup output over the 13-pin cable connection. The
GK-3 control unit has an onboard switch to allow you to easily switch
between regular guitar, divided pickup output, or both, and the VG-99
has internal mixing options to blend the sounds as well.
COSM Amps to the Max
Once you've created a COSM instrument—or
plugged your regular guitar into the GUITAR
INPUT—you can "amplify" it virtually using a
COSM amplifier model. The VG-99 offers 49
COSM amps, from vintage legends to modern
classics. Each amp model offers uncannily
accurate sound replication, as well as a set of
familiar controls (volume, bass, treble, bright
switch, etc.) as found on the real amp. The
amp's speaker system—a critical component of any guitar amp's sound—is
modeled as well, with a selection of five different virtual mics and variable
mic positioning. (You can mix and match speaker types at will, or turn the
speaker models off altogether if desired.)
For a detailed listing of the COSM amps and speakers, see the VG-99
Owner's Manual.
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