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Getting to Know Pro Tools Chapter 1:
Getting to Know Pro ToolsChapter 1:
Topics...
Brief history of Digidesign (Avid Audio)
Modifier Keys & Special Characters
Fundamentals of Digital Audio
The industry standard for music and post production
Multi-track audio recording and editing
Runs on a host computer (software-based)
Hard-disk audio recording, graphical audio editing
What Is Pro Tools?
Audio
MIDI
Notation
Mixing
Post Production
Features of Pro Tools
1984 - Founded as Digidrums by Peter Gotcher and Evan Brooks. Later became Digidesign.
1989 - Digidesign launches the first digital audio workstation system, Sound Tools, for the Apple Macintosh. The company refers to it as "the first tapeless recording studio".
1991 - Digidesign releases the first Pro Tools multitrack system, marking a significant advance in digital audio. The system offered 4 tracks of recording and cost about $6000!
The Story of Digidesign
Evan Brooks & Peter Gotcher
2001 - Digidesign wins a Grammy award for Pro Tools.
2003 - Avid acquires Bomb Factory's extensive product catalog. These products are now included with Pro Tools systems.
2003 - Digidesign wins an Oscar award for their contribution to audio post production for film.
2004 - Avid acquires M-Audio, which now operates as a business unit of Digidesign.
The Story of Digidesign
2005 - Avid acquires Wizoo, which now operates as Digidesign Advanced Instrument Research Group (A.I.R.), but remains largely autonomous, operating out of Bremen, Germany.
2006 - Avid acquires Sibelius, the music software, in a deal worth over $23 million.
2010 - the Digidesign brand name is phased out, with Digidesign products now falling under the Avid product banner.
2011 – Digidesign becomes Avid Audio
The Story of Digidesign
Pro Tools SE
Pro Tools MP 9
Pro Tools 10
Pro Tools HD 10
Pro Tools Software Configurations
Pro Tools HD Series Interfaces
Mbox family (3rd gen)
Eleven Rack
M-Audio Interfaces
Third party hardware
Pro Tools Hardware Configurations
Modifier Keys and Special Characters
Keyboard Commands
/ slash
\ backslash
: colon
* asterisk
? question mark
" quotation marks
' apostrophe
< less-than symbol
> greater-than symbol
| vertical line or pipe
Pro Tools IncompatibleASCII Characters
Basics of Digital Audio
Sound is caused by vibrations
Vibrating objects cause air molecules to vibrate at the same rate
Humans hear vibrations as sound when the frequency is between 20 and 20,000 cycles per second
Sound Basics
Vibrations from different objects create different "shapes"
Each sound is complex - influenced by materials and surroundings
The waveform gives each sound its unique character
Waveform
The pitch of the sound
Measured in cycles per second (CPS) or Hertz (Hz)
1 Hz is the same as 1 CPS
1,000 Hz = 1 kilohertz (kHz)
Frequency
Humans hear frequencies between 20 Hz and 20 kHz
Each time the frequency doubles, the pitch rises one octave
Example - the note “A” has frequencies of: 110Hz, 220Hz, 440Hz, 880Hz, etc.
Frequency
Humans hear frequencies between 20 Hz and 20 kHz
Frequency
The loudness or softness of a sound
Dynamic range of hearing
Measured in decibels (dB)
Threshold of hearing = 0 dB
Threshold of pain = 120 dB
Amplitude
Hearing Damage
88 dB ≈ 8 hours per day
91 dB ≈ 2 hours per day
94 dB ≈ 1 hour per day
97 dB ≈ 30 minutes per day
100 dB ≈ 15 minutes per day
Hearing Damage
103 dB ≈ 7.5 minutes per day
106 dB ≈ 3.75 minutes per day
109 dB ≈ 1.875 minutes per day
140 dB ≈ instantaneous hearing damage
Earplugsetymotic.com $13
Etymotic Research ETY-Plugs ER-20
Humans perceive a doubling of loudness with an increase 10 dB (approximately)
The decibel is a logarithmic ratio (non-linear)
Amplitude
Amplitude
Sound is vibrations in air pressure
A microphone translates the vibrations in air pressure into an electric signal (with waveform, frequency, and amplitude)
This signal is analogous to the original vibrations in pressure
Analog Audio
The electrical signal can be captured on magnetic tape
The signals on tape can be played back through an amplifier and loudspeaker
The speaker translates the electrical waveform into vibrations in the air
Analog Audio
Analog to Digital Conversion
Film captures light at 24 frames per second
Sound must be captured 40,000 times per second (minimum)
A digital “snapshot” of an audio signal is called a sample
Analog to Digital Conversion
Sample Rate
Harry Nyquist (1889-1976)...
For digital audio, a sound must be sampled at twice its highest frequency
A lower sampling frequency will produce strange overtones known as alias tones
Sample Rate
Frequency range of human hearing = 20 Hz to 20 kHz
Full-frequency audio requires a 40 kHz sample rate (at least)
CDs use 44.1 kHz
DV tape uses 48 kHz
Sample Rate
Sample rate determines the highest frequency a digital system can accurately capture.
Sample Rate
Dynamic Range
Full dynamic range of human hearing is 0dB to 120dB
CDs have a dynamic range of 96dB
Popular music typically has a dynamic range of 6 to 10 dB, with some forms of music having as little as 1 dB or as much as 15 dB
Dynamic Range
Loudness is captured using quantization
Each sample is quantified (assigned) to the closest amplitude value
Computers use binary digits called bits (zero or one)
A set of bits is a binary word
Quantization
Bit Depth = Binary Word Length = Resolution
A binary word with 4 bits can have 16 possible values (2 to the 4th)
16 bits = 65,536 possible values (2 to the 16th)
24 bits = 16,777,216 possible values (2 to the 24th)
Bit Depth
Bit Depth determines the dynamic range a digital system can accurately capture.
Bit Depth
More bits = more accurate quantization
More accurate quantization = less noise
Less noise = more usable dynamic range
Bit Depth & Dynamic Range
6 x bit depth ≈ Dynamic range (dB)
8 bits = 48 dB dynamic range
16 bits = 96 dB dynamic range
24 bits = 144 dB dynamic range
32 bits = 192 dB dynamic range
Bit Depth & Dynamic Range
8-bit example
Review
Frequency, loudness, waveform?
Human hearing - frequency range?
Human hearing - dynamic range?
Nyquist?
Bit depth -- dynamic range?
