Generalmusic GRP-800 - Manual (Page 22)

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owner's manual rp800
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owner's manual rp800
Physical Modeling
Physical Modeling is a method of sound synthesis based upon a mathematical model which de scribes the physical construction of the
instrument being simulated. Unlike sampling technology, in which an existing sound is simply recorded at a particular moment in time,
(to remain essentially the same for ev er), the sounds produced by a Physical Model continuously react and respond to the player’s input,
maintaining all the little nuances and im per fec tions which provide the most reliable subconscious as sur ance that the in stru ment being
played is the real thing. A sampled sound can be likened to a “snapshot” of a particular mo ment in time during which an instrument is
being played. It’s like taking a photograph. The goal of Phys i cal Mod el ing is this: Instead of simply recording the final audible product
of a in stru ment like an electric piano, we replicate all the elements which are incorporated into its con struc tion. If the physical
model is constructed carefully and accurately with meticulous attention to detail, the re sult ing sound should be ex act ly like the real thing
and, more importantly, the experience of playing and interacting with the in stru ment should be similarly convincing. In the Rp 800, all
the acoustic piano sounds are created by combining sample playback with Generalmusic’s Natural String Resonance, Damper Phys i cal
Model, Ad vanced Re lease and FADE tech nol o gies, (described below). Other instruments such as RHODES, WURLI and CLAVINET are
created using pure Physical Modeling.
TECHNOLOGY
The Rp 800 is powered by Generalmusic’s break-through technology DRAKE. DRAKE (Dsp-Risc-Advanced-Keyboard-Engine)
is the ultimate DSP: probably the most advanced piece of musical hardware in the world. Its 32-bit and 50-MIPS internal
structure and its totally programmable software architecture make this processor so fast and powerful that any kind of algorithm,
from Wavetable to Physical Modeling, can be implemented in real time, either in generation or in post-processing. Using the
Physical Modelling power offered by DRAKE, Generalmusic has created and patented a number of new algorithms which
replicate some of the world’s most famous vintage instruments like Rhodes™, Wurlitzer™ and Clavinet™. DRAKE has found
unanimous, enthusiastic appraisal from experts in these fields.
FADE - Filter Algorithm Dynamic Emulation
Reproduction of the complex harmonic and dynamic changes which take place as you increase or de crease the velocity of a key-strike on
a piano have always presented a serious problem for traditional sam ple-playback tech nol o gy. The only practical way to re pli ca te these
changes has been to select three or four distinctly dif fer ent levels and switch between these according to the velocity with which the key
is struck. This produces the unnatural effect of having clearly audible steps between different velocity levels, further diminishing the
authenticity of the sound reproduction. Unlike the velocity-switching meth ods used in other elec tron ic pianos, Generalmusic’s unique
FADE technology utilizes only one specially configured sound source per note. At the heart of the FADE engine is a extensive database
which can be used to look up the precise harmonic content of any note played at any velocity level. Whenever a note is played, the FADE
engine analyzes the velocity of the key-strike and constructs, in real-time, a model of the nec es sary har mon ic con tent for that particular
note played at that velocity. The note’s sound source is pro cessed by the FADE engine with appropriate harmonic content being added
or subtracted ac cord ing ly. In practice, FADE tech nol o gy provides seamless transition from pianissimo all the way through to for tis si mo for
each note without any audible switching.
Advanced Release Technology
The particular sound of a piano string being stopped by a damper while in motion is replicated by Generalmusic’s unique Ad vanced Re-
lease Technology. Sample based electronic pi anos traditionally use a en ve lope generator to control what happens when a key is released.
This simply allows the sample loop to continue playing for a set period of time until its amplitude is finally reduced to zero by the envelope
generator. In an acoustic piano, vibrating strings are silenced when a felt damper comes into contact with the moving string. When this
happens, depending on how hard the key was struck and the length of the string itself, certain frequencies are damped earlier than oth-
ers while some other frequencies are even accentuated, (anyone who ever studied how to produce harmonics on a guitar will recognize
this principle). This produces a distinctive harmonic “ring” as the different fre quen cies in the string’s tone dis si pa te through out the piano
soundboard. This Advanced Release Tech nol o gy in the Rp700 series simulates these phe nom e na with complete accuracy throughout the
88 note range.
Damper Physical Model
Another technology patented by Generalmusic is Damper Physical Model. Whenever the damper pedal is depressed, the damper physi-
cal model simulates the effect of sym pa thet ic resonance being produced by the strings which the action of the pedal has now left free to
res o nate. Use the damper pedal to hear the effect of the Damper Phys i cal Model by comparing the sounds of notes played in the highest
octave of the in stru ment with and with out the damper pedal de pressed.
Natural String Resonance
This physical modeling technology, patented by Generalmusic as Natural String Resonance, allows all of the complex harmonics normally
produced by a piano’s soundboard to be faithfully re pro duced. This means that a note’s individual sound will always be slightly different
depending upon which other notes are currently being held, (and consequently which strings are un-damped and free to resonate in sym pa thy
with the note played). If you hold down a low C and let the note decay, the strings for that note are still un-damped for as long as the key
remains depressed. If you now strike another C higher up the keyboard, (stac ca to), you will hear the sympathetic resonance of the low C
strings in response to the new note played. This natural effect replicates exactly what hap pens inside a grand piano. If you experiment with
different combinations of notes you will hear harmonic colors particular to each. Because this effect is produced by physical modeling and
not by samples or DSP effects, the result is a musically and technically ac cu ra te simulation of a piano’s soundboard and virtually infinite
combinations of har mon ics can be produced.