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Petelin, Roman, and Yury
Petelin.
PC Music Home Studio: Secrets, Tips, &
Tricks
Wayne: A-LIST, 2002.– 640 p.
ISBN:1931769079
Click here to buy at Amazon.com
We dedicate this book to
our daughter and granddaughter, Anna.
Introduction
The development of software intended for sound
processing and music editing is progressing at a rapid rate, and
the functionality of musical software is constantly being
improved and enhanced. This is not only due to the fact that the
mathematicians and engineers developing this software are
mastering the secrets of musical art, but also because they
suggest new technical and mathematical methods of solving tasks,
both purely musical ones and those that are both musical and
acoustic. It thus gradually happend that musical skills and
advanced PC user skills are no longer sufficient for someone who
wishes to use the PC for creative activity. Currently, if you
want to create music on your PC, you'll need to master scientific
terminology, understand the ideas behind operations on sound
data, and know the algorithms for processing musical material
implemented in musical software.
Of course, it is rather difficult to master the
scientific basics of all the new technologies implemented in
musical software. In these early years of the 21st century,
musical software for the PC has managed to employ the results of
scientific investigations in the fields of mathematics, technical
cybernetics, and signal processing theory. For example:
- Optimum processing, correlation, and
spectral analysis of signals exposed to interference with
various statistical properties
- Synthesis of sounds with a specified
time-frequency distribution in non-traditional orthogonal
bases
- Adaptive methods of analog-to-digital
conversion
- Polynomial approximation of the
amplitude-frequency responses of the filters
- Elimination of distortions using signal
interpolation with the maximum likelihood method
Even recent advances in the field of artificial
intelligence and psycho-acoustics are now serving the needs of
music.
It is neither fair nor realistic to require the
musician to master all of the above-listed skills. Such a task is
only within the power of those with encyclopedic knowledge.
Still, it is impossible to accomplish anything without an
understanding of some principally important aspects.
Contemporary books on the theory of signals
contain several aspects that are fundamentally important for the
sound engineer or sound producer: statistical radio engineering,
spectral theory, theory of digital signals, information on analog
and digital filters, etc. However, these books are mainly
intended for mathematically skilled radio engineers, not
musicians. For example, a great number of awkward mathematical
expressions mask from the end-users the ideas behind the physical
processes under consideration. In addition, even if you do not
lose your temper and manage to carefully follow this labyrinth of
formulas, it is still very difficult to find the point where
mathematics intersects with music. Many of these books never even say
a word on music. Naturally, scientific literature and
literature on music theory exist in different dimensions.
Actually, this reasoning was partially what led
us to the idea of writing a book, where, besides description of
specific musical software and techniques of their usage, we could
provide the theoretical information necessary to understand the
basic idea of sound processing algorithms. On the other hand, we
have also given ourselves the general goal of discussing
fundamental ideas using the minimum number of mathematical
formulas. When selecting the theoretical materials to be included
in this book, we decided to limit ourselves to describing only
the basic methods, algorithms, and approaches implemented in the
software considered in the book.
If we tried to describe this book using one and
only one phrase, we'd say that this book is on sound synthesis
and sound processing. We intend to cover the following musical
software:
- A sound editor
- A virtual mixer
- A virtual studios
- A sample editor
- Several plug-ins intended for digital
mastering
To work efficiently with these programs, you
need to properly understand spectral representation of signals,
digitization of analog signals, analog and digital filtering, and
dynamic processing.
We'd like to emphasize that if we were
describing how to use some sound editor other than Cool Edit Pro,
then it probably wouldn't be necessary to discuss mathematics and
signal theory. However, a detailed investigation of Cool Edit
Pro's functionality and capabilities allowed us to draw the
following conclusion: Cool Edit Pro is the sound editor that
implements the most advanced methods of signal processing. Such
technologies are technologies of the future, ones used in space
exploration. And this statement is not only figurative. Optimal
filtration with an interference background (which was used when
performing radar exploration of Venus) is also used in Cool
Edit Pro for suppression of the noise accompanying a sound track
recorded directly from a microphone. Or, take for example, the
interpolation algorithm that restores the initial form of a clipped signal. This algorithm is similar
to the ones that allow scientists to restore fragments of signals
transferred to Earth from a space apparatus when the signals get
lost due to ionosphere disturbances. And only a radio amateur who
has spent hours (or, perhaps, days) tuning a 4- or 5-stage filter
of a selector station can truly value the capability of
synthesizing a 30th order Bessel filter with an ideal rectangular
amplitude-frequency response with just a couple of mouse-clicks.
The examples provided above represent only a
small part of the advanced signal processing methods implemented
in Cool Edit Pro. Besides these, Cool Edit Pro also provides the
following capabilities:
- Automatic matching of sound track
fragments at the points where the sound wave intersects
the zero level to eliminate clicks
- Universal virtual dynamic processing
devices
- Special effects based on the time delay of
the signal
- Software filters and equalizers capable of
satisfying the most stringent requirements (and
practically the same as hardware devices that would
likely cost you several thousand dollars)
- The ability to influence the listener's
psyche by generating oscillations synchronized with brain
activity rhythms
Generally speaking, we have not encountered a
more sophisticated and advanced sound editor than Cool Edit Pro.
It implements such a variety of advanced scientific ideas and
efficient signal processing algorithms that the theoretical part
of the book could have been limited to explaining just a few of
them.
We also decided that discussion of signal
theory basics must be complemented by covering several practical
aspects, including the following:
- Microphone design and usage
- Mixer design and usage
- The essence of the most popular acoustic
effects
- Filter classification and properties
- Working principles of dynamic processing
devices
- Theoretical basics and techniques of
digital mastering
Naturally, we don't claim to have discovered
something new when describing theory basics. Making scientific
discoveries nowadays is rather difficult. The theory was
formulated long ago, and is currently fully developed. On the
other hand, we were not aiming to create just another thesis,
either. This book is mainly aimed at providing a popular and
easy-to-read description of contemporary scientific knowledge in
the field of signal processing, and attempts to demonstrate their
relation to the problems of musical computer technologies.
Among other problems that we have encountered,
we wanted to overcome the following difficulty. Digitized musical
compositions are non-stationary processes, the spectral analysis
of which requires using current and instantaneous spectrums. Such
spectrums are the kind calculated and displayed by Cool Edit Pro.
However, most textbooks never even mention the existence of the
spectral-time approach to signal analysis. Usually, only
mathematical abstractions - classical Fourier spectrums
calculated at an infinite time interval - are considered. Because
of this, the chapters of our book dedicated to spectral analysis
at finite time intervals might prove to be useful not only for
musicians using their PC, but also to anyone who deals with
various aspects of processing signals of any type.
Another distinguishing feature of our approach
to discussing theory is the attempt to describe quite complex and
advanced concepts in easy and understandable language. We'd like
to point out, however, that the theoretical aspects covered here
are rather complex, and can't be explained using too simplistic
of an approach. To get a clear understanding of these topics,
it's necessary to do some intellectual work. It's quite a job,
both for your mind and your imagination.
All the theoretical materials presented here
are coordinated with the elements of the software discussed in
the book.
Besides the Cool Edit Pro sound editor that we
have already mentioned, we will also cover the virtual toolkits
that have swiftly gained popularity among computer musicians. We
are speaking here about Nemesys Gigastudio 160 and Reason. These
applications (especially Reason) are powerful and rather complex
virtual tools intended for sound and music synthesis, and also
capable of replacing extremely expensive hardware sound studios.
Even in 1997, we covered virtual synthesizers in
one of our publications. At that time, however, they were more
like toys. The main problem that prevented virtual synthesizers
from being widely accepted was the fact that the time interval
separating the instances of a key being pressed and the sound's
generation was perceivable by ear. Technology has made
significant advances since then, however. Modern PCs have become
faster and more powerful, CPU clock speeds have grown by
approximately 10 times, and large amounts of RAM (gigabytes) are
no longer exotic. Developers of software whose names contain the
"Giga" prefix haven't been asleep at the job either.
They have managed to find convenient data formats for storing
sound information, and thus have optimized playback procedures.
With the release of Reason, the dream of
musicians of implementing a full-featured virtual studio has
become a reality. Several years ago, the difference between
compositions created in home and professional studios was obvious
and clearly noticeable. The situation now has changed radically.
The virtual toolkits and several hundreds of CDs with sound
samples give a chance of success even to amateurs.
Thus, having briefly described the
distinguishing features of the book and its concepts, let us
consider the book's structure, which comprises this introduction,
and 24 chapters split into 5 parts.
Part I:
Acoustic Signal Conversion Theory Basics
The first part includes 4
chapters:
Chapter 1:
Acoustic Signals and Their Basic Properties
Chapter 2:
Spectral Representation of Signals
Chapter 3:
Filtering
Chapter 4:
Dynamic Processing of Acoustic Signals
Part II:
Microphones, Mixers, and Effects
The second part is comprised of 2 chapters:
Chapter 5:
Working with the Microphones and Mixers
Chapter 6:
Sound Effects
Part III: Cool
Edit Pro - a Multitrack Sound Editor
The third part consists of 12 chapters:
Chapter 7:
Getting Started
Chapter 8:
Working with the Main Window Using Waveform View Mode
Chapter 9:
The File Menu - Working with Files
Chapter 10:
The Edit Menu
Chapter 11:
The View Menu - Display Management
Chapter 12:
The Transform Menu - Transforming Audio
Chapter 13:
The Generate Menu - Sound Generation
Chapter 14:
The Analyze Menu - Analyzing Audio Data
Chapter 15:
The Favorites Menu - Creating a List of the Most Often
Used Operations
Chapter 16:
The Option Menu
Chapter 17:
The Window Menu - Managing the Main Window Pages
Chapter 18:
Multitrack View - Multitrack Editing Mode
Part IV:
Virtual Toolkit
The fourth part is comprised of
3 chapters:
Chapter 19:
Nemesys GigaStudio 160 (V.2)
Chapter 20:
Creating Your Own Sampler Libraries Using GigaStudio Instrument
Editor 2.0
Chapter 21:
Reason - a Virtual Sound Studio
Part V: Digital
Mastering
The fifth part contains 3 chapters:
Chapter 22:
Theory
Chapter 23:
Mastering with T-RackS 24
Chapter 24:
DirectX Plug-Ins Useful for Mastering
We actively use all software covered in this
book in our everyday work. For example, it is the multitrack
environment of the Cool Edit Pro sound editor that we used when
preparing all materials for our radio and TV programs. When
writing this book, we also put to use our experience in teaching
musical computer technologies.
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