8
Table Of Contents
- Logic Express 8 Instruments and Effects
- Contents
- Introduction to the Logic Express Plugins
- Amp Modeling
- Delay
- Distortion
- Dynamics
- EQ
- Filter
- Imaging
- Metering
- Modulation
- Pitch
- Reverb
- Specialized
- Utility
- EVOC 20 PolySynth
- EFM1
- ES E
- ES M
- ES P
- ES1
- ES2
- The ES2 Parameters
- Tutorials
- Sound Workshop
- Sound Design From Scratch, Filter Settings, Digiwaves
- Three Detuned Sawtooth Oscillators and Unison Mode
- Extremely Detuned Monophonic Analog Sounds, Effects
- Clean Bass Settings With One Oscillator Only
- Distorted Analog Basses
- FM Intensity and Frequency
- Controlling FM Intensity by an Envelope and FM Scaling
- FM With Drive and Filter-FM
- FM With Digiwaves
- FM With Wavetables
- Distorted FM in Monophonic Unison
- FM With Unusual Spectra
- Slow and Fast Pulse Width Modulations With Oscillator 2
- Pulse Width Modulation With Two Oscillators, PWM Strings
- Ring Modulation
- Oscillator Synchronization
- First Steps in Vector Synthesis
- Vector Synthesis—XY Pad
- Vector Synthesis Loops
- Bass Drum With Self-Oscillating Filter and Vector Envelope
- Percussive Synthesizers and Basses With Two Filter Decay Phases
- Templates for the ES2
- Sound Workshop
- EXS24 mkII
- Learning About Sampler Instruments
- Loading Sampler Instruments
- Working With Sampler Instrument Settings
- Managing Sampler Instruments
- Searching for Sampler Instruments
- Importing Sampler Instruments
- Parameters Window
- The Instrument Editor
- Setting Sampler Preferences
- Configuring Virtual Memory
- Using the VSL Performance Tool
- External Instrument
- Klopfgeist
- Ultrabeat
- GarageBand Instruments
- Synthesizer Basics
- Glossary
- Index
Appendix Synthesizer Basics 419
Subtractive Synthesis
Subtractive synthesis is synthesis using filters. All analog and virtual analog synthesizers
use subtractive synthesis to generate sound. In analog synthesizers, the audio signal of
each voice is generated by the oscillator. The oscillator generates an alternating current,
using a selection of waveforms which contain differing amounts of (more or fewer)
harmonics. The fundamental (or root) frequency of the signal primarily determines the
perceived pitch, its waveform is responsible for the basic sound color, and the
amplitude (level) determines the perceived volume.
Cutoff and Resonance—Illustrated With a Sawtooth Wave
This picture shows an overview of a sawtooth wave (a = 220 Hz); The filter is open, with
cutoff set to its maximum, and with no resonance applied. The screenshot shows the
output signal of Logic Express’s ES1, routed to a monophonic Logic Express output
channel. The recording was performed with the Bounce function of this channel, and is
displayed in the Sample Editor at a high zoom setting.
∏ Tip: Classic synthesizer literature indicates the use of the sawtooth wave to create a
sound similar to that of a violin. The rich and full sound of the sawtooth wave is the
most popular synthesizer waveform, and serves as a basis for synthetic string and brass
sounds. It is also handy for synthesized bass sounds.
When Michelangelo was asked how he would manage to cut a lion out of a block of
stone, he answered, “I just cut away everything that doesn’t look like a lion.” This, in
essence, is how subtractive synthesis works: Just filter (cut away) those components of
sound which should not sound—in other words, you subtract parts of the oscillator
signal’s spectrum. After being filtered, a brilliant sounding sawtooth wave becomes a
smooth, warm sound without sharp treble. Analog and virtual analog synthesizers are
not the only devices that make use of subtractive synthesis techniques. Samplers and
sample players also do so, but use modules which play back digital recordings
(Samples) in place of oscillators (that supply sawtooth and other waveforms).