ETR II FINAL Flashcards
Channel Path
- Mic preamp output
- EQ
- Small Fader Input
- Direct Channel Output
- Multitrack Input
Monitor Path
- Multi-track output
- Input of Large fader
- Mix bus
- Master fader
- Monitor select
Insert Send + Insert Return
There is a separate insert send+return for the Small and Large faders.
Multi-track Output
This is a direct patch point for the output of a track from Pro Tools. This is the “O” in the I/O setting for each track in Pro Tools.
Multi-track Input
This is the direct patch point for the input to Pro Tools. This is the “I” in the I/O setting for each track in Pro Tools.
Aux Send Outputs
“Sends” the signal to an outboard Effects Device- e.g- a Digital Reverb device or a Digital Delay Device.
Stereo Return Inputs
These patch points are where you would patch the output of an effects device to have the reverbs output “returned” to the Mix Bus as a Parallel Effect
***You must also make sure the small STA button is engaged on each stereo that is being used to have that return in the Mix Bus.
Line Input
This is the patch point for line level signals directly to the input to one of the large monitor faders on the console.
Stereo Output L- STA –R
Output of the mix bus.
Five parameters of compression
Threshold, Ratio, Attack, Release, Makeup Gain
6 Track 1 MNTR In L+R
Patch point to monitor external sources of audio that are not going to the Mix Bus but only to the monitors.
Threshold
Sets the amplitude above which compression is to occur and below which compression is to stop.
- As long as signal remains below this level, it will not be compressed.
- When signal exceeds threshold, the compressor attenuates the signal.
Ratio
Amount of compression - compares the amount of input signal above the threshold to the amount of attenuated output above the threshold.
- 4:1 ratio describes a situation where the input level above the threshold is to be four times higher than the output above threshold (4 dB above in becomes 1 dB out).
- Only applies to portion of signal above the threshold.
- Ratio below 10:1 indicates compression.
- Ratio above 10:1 indicates limiting.
Attack
The speed with which the signal is attenuated (how quickly the compressor fully kicks in after the threshold has been exceeded.
Release
Sets the speed of the signal as it moves towards unity gain.
Makeup Gain
Turning the signal back up by a fixed amount.
Sidechain
A gain change device that can significantly change the sound of compression.
Tube compressors
- Level detector circuit sends a voltage to the tube that directly drives the gain of the tube.
- Produces distortion
- Includes the reaction time of the tube as the gain is changed.
- slower
Optical Compressors
- Use interaction between a light source and a light sensitive resistor to influence gain.
- Essentially illuminates a light which then shines on a photovoltaic cell - amplitude of the signal through the compressor is driven by the resistance of the photocell in reaction to the amount of light shining upon it.
- The time it takes the bulb to turn on and off is synonymous with the attack and release of the compression.
- Slower
VCA Compressors
- Leverages a voltage controlled amplifier to affect gain of the compressor.
- Fastest and smoothest.
Pumping
Generally unwanted audible artifact of compressor release revealed by the slow or unchanging amplitude of the audio signal being compressed.
Expander
Signals that fall below a designated threshold are reduced by a specified ratio.
Gate
When the input signal falls below the threshold, the gate closes and passes no signal.
Upward expander (rare)
Increases the amplitude when the signal exceeds the threshold in an attempt to raise the signal without distortion.
Downward expander
Decrease the amplitude when it falls below the threshold in an attempt to lower the level of the noise.
Threshold (expansion + gating)
determines amplitude below which attenuation is triggered into action
- When amplitude sinks lower than the threshold, however, the expander begins to attenuate the signal
Slope (expansion + gating)
Degree of expansion
- Compares the level below the threshold of the input to the level below the threshold of the output
Attack (expansion + gating)
How fast the signal is attenuated
- How quickly the expander returns to unity gain after the amplitude of the signal has passed upward through and above the threshold.
Release, Fade or Decay (expansion + gating)
Speed of the imagined fader within the machine as it moves down.
Hold (expansion + gating)
Minimum length of time that the expander/gate must wait after the signal crosses the threshold before any attenuation is allowed to occur.
Expansion
Minimizes outside noise, separates the volume of the wanted signal from the volume of the unwanted signal.
Noise Gating
Cleaning up signals on tracks like snare in the tom tracks, or kicks in a snare track.
- Can patch an expander/gate on the during mixdown.
- Some low level noises like tape hiss or amp buzz can be completely silenced by a noise gate.
Gating Through Waveform Editing
Work through each and every track and edit out any and all unwanted noises - find the parts where the singer is not singing and cut them out.
Gating
Alter attack and decay envelop to make the sound more pleasing to the ear, but still natural and realistic.
Coincident
- Two directional mics angled apart with capsules nearly touching
- Stereo effect produced by level differences between two channels
- Images are sharp
- Stereo spread ranges from narrow to accurate
- Mono-compatible
Near-Coincident
- Two directional mics angled apart with a few inches between the capsules
- Stereo effect produced by level and time differences between channels
- Images are sharp
- Stereo spread tends to be accurate
- Sense of air and depth
Spaced Pair or AB Pair
- Two omni mics spaced several feet apart
- Stereo effect produced by time differences between channels
- Off center images are diffused
- Stereo spread tends to be exaggerated
- Provides a warm sense of ambience
- Phase differential could be problematic
XY
Coincident: 90 degree angle with cardioids
- dryer than the blumlein
Blumlein
Coincident: 90 degree angle with 3 bi-directional microphones.
Mid Side
Coincident: one cardioid center mic and one bi-directional mic.
- Bi-directional is copied and polarity reversed
- Adjustable stereo image after recording
- Cardioid facing signal, bi-directional facing sideways right under
ORTF
Near-Coincident: cardioids angled 110 degrees apart and spaced 17 cm.
NOS
Near-Coincident: Cardioids angled 90 degrees apart and spaced 30 cm
OSS
Near-Coincident: omnis spaced 16.5 cm and separated by a foam covered disk of 28 cm diameter.
Decca Tree
Spaced Pair or AB Pair: uses 3 Neumann M50 Omni microphones in a left center right configuration.
Feedback
Parameter of digital delay devices that allows an engineer to make the delay time repeat more than once.
Flanging
Short delay (under 15) with modulation.
- Short delays have spectral effects on the sound
Parameters of Digital Delay
depth, rate, shape
To find BPM in a 4/4
time 10 full beats for a ¼ note delay
Short-time (1ms - 20ms)
- Spectral Effect: due to short delay times the delayed signal when combined
- Will create a comb filter when paired with original frequency
- Phasing: breaks the signal into different frequency bands that are then phase shifted by different amounts - 90, 180, 270, etc…
- This produces non linear frequency phase responses
- Flanging: short modulating delay - delay and phase shift across all frequencies
Medium time (20ms - 50ms)
- Spreaders: either mono or stereo with or without modulation
- Chorusing: multiple panned delays with various amounts of modulation
- Pitch Shifting: detuned up and down by equal amounts, starting around 6 cents
Long Delays (50 ms upward)
- Slap Delay: with tape machine or DDL to create the delay depending on tempo - 80-120 ms - decrease tape machine speed for longer delay time
- All Rhythm Delays: 1/16, 1/8, 1/2, etc…
Chamber
Physical space - dedicated rooms or a recording studio.
Mechanical
- Spring: mechanical device
A transducer vibrates the spring, sound waves bounce back and forth along spring until the energy dissipates
Sound quality: lots of low-mid range around 1khz, a boost at 5k, steep roll off above 5k and below 1k - Plates: mechanical device
Uses a steel plate tensioned on a frame - there is a transducer that caused vibrations on the plate, the sound wave travels back and forth on the plate until the energy dissipates
There is a dampening pad on the plate to shorten the vibrations to shorten the decay time
Sound quality: relatively flat response until around 9k, then there is a boost, smooth response
Digital
- Infinite Impulse Response (IIR): digitally produced
Majority of digital reverbs - algorithm based and have the most flexibility with changing parameters
Created using a series of comb filters and all pass filters
Sound quality: very good - able to mimic many natural spaces and mechanical reverbs - Convolution Reverbs: digitally produced
Uses as impulse response to capture a sort of snapshot or blueprint of all of the reflections of a space and can apply those reflections to another signal
Sound quality: best ability to capture the most accurate convolution of real spaces
Pre-Delay
Difference in time of arrival between the direct sound and the subsequent first associated reflection
- Allows you to hear if a space is small or large - provides the most significant aural cue in determining the size
Equalization
frequency dependent gain control
Gently tempers the shape of a sound’s spectral content
Surgically removes unwanted frequencies
Cannot manufacture frequencies that don’t already exist
High Pass
cuts out low frequencies and allows high frequencies to pass unaffected
- Frequencies that are cut and passed are relative to the cutoff frequency
- Slope of the filter measured in db per octave
Low Pass
cuts out high frequencies and passes low frequencies
- Frequencies that are cut and passed are relative to the cutoff frequency
- Slope of the filter measured in db per octave
Band Pass
cuts frequencies outside of a selected band and passes frequencies within it
- Combination of high pass and low pass filter
- Slope of the filter measured in db per octave
Notch
cuts frequencies within a specific band and passes all others
- Combination of high pass and low pass filter
- Slope of the filter measured in db per octave
Shelf EQ
boosts or attenuates program content from a given frequency and extends the gain change above or below that frequency like a shelf
- Slope is a measure of how the frequencies around the turnover are affected
- Relatively gentle slope, or low q
- Low frequency shelf symbol opens to the left
- High frequency shelf symbol opens to the right
Bell Curve
reach its peak boost or cut at the center frequency, and the surrounding frequencies will gradually return to a gain change of 0 dB.
- Resembles the shape of a bell
- Q of a curve is the ratio of the center frequency divided by the bandwidth of the curve - t is analogous to the slope of the curve
- Has an associated bandwidth
- Measured on both sides of a bell curve
- Bandwidth is measured when it is 3 decibels away from the maximum boost or cut of the Center Frequency
- A small Q value equals a wide bandwidth
- A Large Q value equals a narrow bandwidth
Parametric Equalizer
features a frequency selection control that is continuously variable over a wide band of frequencies
- offers the variable of user adjustable Q
- variable Boost or Cut amplitude controls
Graphic Equalizer
Controls imply a graphic display of the resulting frequency response
- Typically spaced at octaves or ⅓ octaves
Phase shift
EQ’s rely in part on capacitors and inductors,which induce tiny amounts of time delay and cause phase shifts
- Vary with frequencies ,filter shape and amount of gain applied
- In moderation it will enhance and clarify the frequencies you are trying to highlight
- Too much phase shift unsurprisingly, smears a sounds harmonics and muddies up your original intentions
- Can dramatically altered gain structure- meaning it will add volume to the signal
Less Is More
Use EQ to attenuate signals, not boost
Passive EQ
- Passive equalizers create tonal changes without using any powered components like transistors, op-amps or tubes in their tone shaping circuits
- Use only passive electronic components—resistors, capacitors, and inductors
- Requires a make-up amplifier to boost the EQ’d signal back up to its original level—and that amplifier may use colorful tubes, transformers, and transistors
- Passive EQ’s have a smooth silky top end and a warm low end
- Passive EQs provide organic tone shaping with low distortion and musical coloration
- utilize inductors, which are coils of wire that act as frequency-dependent resistors to create electrical inductance
