ENGLISH
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5
Pitch bends produced by a pitch bend wheel are not always accurate.
Natural acoustic musical instruments have no “pitch parameter.” Pitch is determined by the
properties of the instrument’s resonant body as well as the condition of the instrument’s
driver. The same applies to Virtual Acoustic Synthesis: in the pitch bend is simulated by
manipulating the appropriate pipe/string length and driver characteristics. As a result, the
pitch bend range may not always be “mathematically” accurate.
With reed instruments such as saxophone or clarinet, highly realistic pitch bends are pro-
duced by controlling both pitch and embouchure at the same time. Since the embouchure
component of the pitch bend behaves with characteristics acoustic unpredictability, precise
pitch bends are not always produced.
6
Some voices don’t respond as expected to EG edits.
The effect of editing envelope generator parameters may not always be as expected — par-
ticularly with plucked string instrument voices such as guitar or bass. This is because the VL
actually simulates the plucking, free oscillation, and muting of the strings rather than simply
using an EG to approximate these events. If the sound of a string voice decays naturally, for
example, setting a long release time will have little or no effect on the actual sound of the
voice. Since the attack and decay portions of the voice also have natural timbre variations,
these can be unnaturally altered by inappropriate EG settings — which is OK if you’re trying
to produce an unnatural effect. Trial and experimentation and the only sure ways to deter-
mine how the EG parameters are going to affect a particular voice.
7
The PLG100-VL is a monophonic tone generator. Why is the “poly” mode initialy
selected when the VL-XG sound module mode is engaged?
This is to provide compatibility between the current XG format and future polyphonic VL-
series tone generators. It also provides a certain degree of compatibility to allow playback of
VL-XG song data on existing tone generators which do not feature the VL-XG extension.
Specifically, to switch the PLG100-VL to the mono mode a “mono mode” command (control
change no.126, value 0-16) is embedded in the song data which, when received by a 32-note
or 64-note polyphonic XG tone generator, switches the appropriate parts to the mono mode.
The same will apply to future polyphonic VL-series tone generators, so no changes will be
required. The PLG100-VL therefore has a “poly” which is automatically selected when a
MIDI “XG on” system exclusive message is received.
Q & A