APPLIED ACOUSTICS SYSTEMS STRINGSTUDIO Uživatelský manuál stáhnout pdf (Strana 37)

4.7 The Geometry Module 37

4.7 The Geometry Module

The Geometry module is used to set the location of the point

of action of both the excitator and the damper on the string. These

positions are adjusted with the Position knobs under the Excitator and

Damper labels and can be set to any value between zero (the point of

ﬁxation of the string) and half the length of the string (value of 0.5).

When the Abs (absolute position) LED is switched on, the posi-

tion of the excitator or the damper is ﬁxed whatever the note played.

This would be the case, for example, on a guitar when the player keeps the position of the pick

ﬁxed while varying the effective length of the string when changing notes. The actual position is

determined with the setting of the Position knob applied to the length of a string corresponding to

C3 (middle C). Note that when the note played is such that the string length corresponding to this

note is shorter than this position, the excitator or the damper will follow the ﬁxation point of the

string.

When the Abs LED is in its off position, the location of the damper or the excitator is changed

in order to always correspond to a certain fraction of the length of the string. This fraction of the

string length is that determined by the Position knob. This type of geometry is found in instruments

such as the piano where hammers excite strings at about 1/7 of their length.

Note that both the excitator and damper position can be modulated with the pitch signal or

velocity signal received from the keyboard. The modulation will be relative to the value set by the

excitator or damper Position knobs.

4.8 The Pickup module

The Pickup module reproduces the functioning of magnetic pick-

ups such as found in electric guitars or electric pianos. This type

of transducer is sensitive to the motion of a nearby metallic string.

When a string vibrates near a pickup, the latter outputs an oscillating

signal at the same frequency as that of the string and proportional to

the string velocity.

The only parameter to adjust in the Pickup module is its position relative to the string which

affects the waveform of its output.

Note that usually, the signal from a pickup is sent directly to an external device such as an

ampliﬁer. In other words, the body of the instrument does not play any role in the radiation of

the sound. In String Studio, this behavior is obtained when the Pickup module is on and both the

Filter and Body modules are switched off. When the Pickup,theFilter and Body modules are on,

the output signal from the Pickup is ﬁltered by the Filter and Body modules. Finally, when the

Pickup module is switched off, the output signal from the String is sent directly to the Filter and

Body module.

1 2 ... 32 33 34 35 36 37 38 39 40 41 42 ... 69 70

Žádné komentáře

APPLIED ACOUSTICS SYSTEMS STRINGSTUDIO Uživatelský manuál Strana 37