# Shared Flashcard Set

## Details

AUDIO MEASUREMENT SYSTEMS
MIDTERM STUDY GUIDE
86
Engineering
07/16/2013

Term
 WHAT ARE THE MAIN REASONS FOR SOUND SYSTEM MEASUREMENT?
Definition
 •Maintenance•Legal•Artistic
Term
 WHAT ARE THE 5 BASIC TEST SIGNALS USED FOR SOUND SYSTEM MEASUREMENT?
Definition
 •Pink Noise•White Noise•Sine Waves•Shaped Noise •Broadband Pulse
Term
 WHAT IS WHITE NOISE?
Definition
 •Equal energy per frequency
Term
 WHAT IS PINK NOISE?
Definition
 •Equal energy per octave
Term
 WHAT ARE THE 2 MOST COMMON WEIGHTING CURVES USED FOR SPL METERS?
Definition
 •A and C
Term
 WHICH DIMENSION IS A REAL TIME ANALYZER MISSING?
Definition
 •Time
Term
 WHAT IS THE FOURIER TRANSFORM?
Definition
 •A mathematical calculation – converts amplitude vs. time into amplitude vs. frequency
Term
 WHAT MEASUREMENT SYSTEMS IN SHOW PRO PRIMARILY USE FFT’S?
Definition
 •SIM and SMAART
Term
 WHAT DOES TEF STAND FOR?
Definition
 •Time Energy Frequency
Term
 WHAT DOES MLS STAND FOR?
Definition
 •Maximum Length Sequence
Term
 EASE WAS DEVELOPED BY?
Definition
 • Dr. Wolfgang Ahnert
Term
 IN EASE WHAT OTHER TYPES OF ROOM INPUT METHODS ARE THERE OTHER THAN VERTEX BY VERTEX?
Definition
 •Extrude •Insert shape 3D •Insert - Load prototype
Term
 NAME THE FIVE TYPES OF 3D SHAPES YOU CAN INSERT?
Definition
 •Cuboid•Pyramid•Cone•Cylinder•Cupola
Term
 INTERIOR SURFACES ARE WHAT COLOR?
Definition
 •Yellow
Term
 IN EASE WHAT IS THE HOT KEY TO SAVE AND APPLY?
Definition
 •F6
Term
 WHY ARE MOST ROOMS MODELED IN THE NEGATIVE Y AXIS?
Definition
 •That is the direction speakers are facing when inserted
Term
 WHAT IS THE COMMAND FOR CUTTING A FACE INTO TWO FACES?
Definition
 •Fixed Cut
Term
 WHAT IS THE HOTKEY TO DELETE UNATTACHED VERTICES?
Definition
 •Control + Shift + F12
Term
 WHEN ADDING FLOOR TO CEILING COLUMNS IN A ROOM YOU MUST?
Definition
 •Use “is coat of”
Term
 WHAT ARE SOME OF THE PROTOTYPES AVAILABLE IN EASE?
Definition
 •Amphitheater •Auditory •Basilica •Church •Coliseum •Gothic Dome •Multipurpose •Octagon •Opera •Redoubt •Shell •Sporting Hall •Stadium •Station •Theater •TriCube
Term
 DESCRIBE POLARITY?
Definition
 •A source or signal is either pushing positive or negative
Term
 DESCRIBE PHASE IN FOUR WORDS?
Definition
 •Frequency dependent time delay
Term
 NAME THREE WAYS TO REVERSE POLARITY?
Definition
 •Swap pins 2&3 in cable•Reversing the speaker wiring•Polarity switch or setting (Console Processor Amp)
Term
 TWO SIGNALS OF EQUAL AMPLITUDE AT 0 DEGREES OFFSET WILL RESULT IN?
Definition
 •6dB of coupling
Term
 TWO SIGNALS OF EQUAL AMPLITUDE AT 180 DEGREES OFFSET WILL RESULT IN?
Definition
 •Full Cancellation -100dB
Term
 TWO SIGNALS OF EQUAL AMPLITUDE AT 120 DEGREES OFFSET WILL RESULT IN?
Definition
 •No coupling or cancellation
Term
 READING PHASE TRACES; IF THE TRACE IS ANGLED TO THE LEFT IT IS?
Definition
 •Lagging
Term
 READING PHASE TRACES; IF THE TRACE IS ANGLED TO THE RIGHT IT IS?
Definition
Term
 READING PHASE TRACES; IF THE TRACE IS ANGLED STRAIGHT UP AND DOWN IT IS?
Definition
 •Wrapping or wrap around
Term
 WHAT APPLICATIONS IN SIM II 2.0 IS LAB MODE USED FOR?
Definition
 •Standalone measurement and research
Term
 WHAT ARE THE STATUS PANELS IN SIM II?
Definition
 •Information windows at the bottom of the screen
Term
 WHAT DOES DATA REJECTED MEAN IN SIM II?
Definition
 •One of the ports has reached overload
Term
 IN SIM II WHAT ARE THE 2 WINDOWS IN SPECTRUM MODE CALLED?
Definition
 •Reference and Measurement
Term
 IN SIM II WHAT ARE THE DIMENSIONS IN THE DELAY FINDER SCREEN?
Definition
 •Relative amplitude vs. time (bottom window is a 10x magnification of the upper window).
Term
 IN SIM II WHAT DOES FIFO STAND FOR?
Definition
 •First in First out
Term
 IN SIM II WHAT IS THE HOT KEYS FOR THE TRACE OFFSET?
Definition
 “+/-“ key
Term
 IN SIM II WHAT IS THE HOTKEY TO TURN THE GENERATOR – PINK NOISE ON?
Definition
 Alt+G
Term
 IN SIM II WHAT IS THE HOTKEY TO SET THE AUTOSET DELAY?
Definition
 F3
Term
 WHAT ADVANTAGES DOES A PARAMETRIC EQ HAVE COMPARED TO A GRAPHIC EQ?
Definition
Term
 WHAT IS COMPLIMENTARY EQUALIZATION?
Definition
 •Creating the opposite in gain •Matching the Bandwidth•Matching the Center frequency
Term
 WHAT IS ERROR IN CENTER FREQUENCY?
Definition
 When the center frequency of the anomaly and the center frequency of the correction do not match.
Term
 WHAT IS ERROR IN BANDWIDTH?
Definition
 When the bandwidth of the anomaly and the bandwidth of the correction do not match.
Term
 WHAT IS COMB FILTERING?
Definition
 Two signals arriving at different times near equal amplitude; causing cancellation of linear frequencies.
Term
 WHAT ARE THE TWO INDEPENDENT FACTORS THAT DETERMINE THE MAGNITUDE AND FREQUENCY RESPONSE OF COMB FILTERING?
Definition
 •Time Offset•Level Offset
Term
 HOW DO YOU CALCULATE FOR COMB FILTERING?
Definition
 •F = 1/t(seconds) •1st null = f/2
Term
 WHY IS IT CALLED COMB FILTERING?
Definition
 On a linear scale it looks like the bristles of a comb.
Term
 WHAT ACTIONS COULD YOU TAKE TO REDUCE COMB FILTERING?
Definition
 •Delays•Level offset•High Pass Filters•Noise Gates
Term
 WHY ARE EQ’s BLAMED FOR POOR RESULTS WHEN TRYING TO CORRECT COMB FILTERING?
Definition
 It’s a time problem, it cannot be corrected with frequency.
Term
 WHAT 3 APPLICATIONS THAT SIM 3 CAN BE USED FOR?
Definition
 •Device Analysis•Speaker Analysis•Room Analysis
Term
 IN SIM 3 WHAT ARE THE 2 SCREENS IN THE FREQUENCY RESPONSE TAB IN THE "GROUP" VIEW?
Definition
 •Result •Processor/Room
Term
 WHAT ARE THE 3 WINDOWS IN THE BAND SPECTRUM SCREEN AND WHAT IS THEIR SIGNIFICANCE?
Definition
 •Console •Processor •Mic
Term
 IN SIM 3 HOW MANY DIFFERENT MODES ARE AVAILABLE?
Definition
 •Free Run•Single System•Lobe Study•Combine Systems•Show•Mic EQ •Console Check•Mic Compare
Term
 WHAT ARE THE 2 TYPES OF SPECTRUM ANALYSIS VIEWS IN SIM 3?
Definition
 Band Spectrum and Line Spectrum
Term
 WHERE DO YOU TOGGLE PHANTOM POWER FOR SIM 3?
Definition
 On the front panel tab
Term
 WHAT IS THE MOST SIGNIFICANT UPGRADES MADE TO SIM 3 FROM SIM 2?
Definition
 Ability to do multi-channel and CD-Rom
Term
 WHAT ROLE DOES THE GALILEO PROCESSOR PLAY IN SIM 3 MULTI-CHANNEL?
Definition
 Line Switcher
Term
 WHAT FUNCTION OF THE GALILEO PROCESSOR CAN BE CONTROLLED FROM SIM 3?
Definition
 The Muting
Term
 How many mics can you input to 1 mic switcher?
Definition
 8
Term
 Name the Branch Measurement Points?
Definition
 •Console•Processor•Mic
Term
 Name the three frequency responses in a branch.
Definition
 •Processor•Speaker+Room•Result
Term
 What does LONAXN Mean?
Definition
 Left ON Axis Near
Term
 What does ROFFAXF Mean?
Definition
 Right OFF Axis Far
Term
 What are the two variables for a Primary Mic Placement?
Definition
 +/- 10 degrees on axis & center of listening area
Term
 What is the Inverted EQ?
Definition
 An upside down EQ, cuts look like boosts and boosts look like cuts. Used as a reference when tuning a system.
Term
 What is Single System?
Definition
 When measuring one system at a time, the other systems are muted.
Term
 What is Lobe Study?
Definition
 The primary system being studied is muted while looking at the other systems interacting. Look for bleed-over.
Term
 Name the six traces of the following SIM Screen shot. [image]
Definition
 [image]
Term
 What are the 7 steps to Analyze a Stereo System?
Definition
 •Preliminary Prep•Interfacing SIM w/Sound System•Initial Testing•Testing for Harmonic Distortion•Finding the Delay offset•Initial EQ•Adding the Systems Together•Show Mode
Term
 What kind of mic is used for acoustic measurement?
Definition
 Omni Directional w/ Flat Freq Response
Term
 What happens when a measurement microphone is angled 90 degrees from the source?
Definition
 At 5k and above starts to roll off
Term
 Where should the secondary mic placement be?
Definition
 Anywhere in the listening area
Term
 Typically, where should we not place the measurement microphone?
Definition
 •Near walls or Pillars•Exact center of rooms•In the Aisles (expect in line array situations)
Term
 When should we use sitting height for the measurement microphone position?
Definition
 In Recording Studios and Frontfills (First 3-4 rows)
Term
 Why does Auto-EQ not work?
Definition
 Because it is Blind
Term
 What are the initial EQ considerations in Studios?
Definition
 •Sweet spot must be wide enough for both ears.•Pay close attention to the s/n or coherence.•Only EQ for the low q problems (wide) – don’t worry so much about the high q issues.
Term
 Which company manufactures the Galileo?
Definition
 Meyer Sound
Term
 What is the name of the software used with the Galileo?
Definition
 Compass
Term
 What kind of cable is used to connect the Galileo to the measurement system?
Definition
 SIM BUS Cable
Term
 NAME THE 3 FORMS OF PARTICLE MOTION.
Definition
 •Cylindrical wave •Transverse •Longitudinal
Term
 WHAT IS THE FORMULA TO CALCULATE THE SPEED OF SOUND, KNOWING ONLY THE TEMPERATURE?
Definition
 C=49√459.4+F
Term
 HOW DOES TEMPERATURE AFFECT THE VELOCITY OF SOUND?
Definition
 •If the temp goes up the speed of sound goes up.•If the temp goes down the speed of sound goes down.
Term
 WHAT IS WAVELENGTH?
Definition
 •The distance a wave travels to complete one cycle
Term
 HOW DO YOU CALCULATE WAVELENGTH?
Definition
 •1130/Hz(frequency)
Term
 HOW DO YOU CALCULATE OCTAVE RELATIONSHIPS?
Definition
 •2:1 ratio a doubling of frequency
Term
 HOW DO YOU CALCULATE HARMONICS?
Definition
 •Multipliers of the fundamental
Term
 WHAT IS THE FORMULA TO CALCULATE A RANGE OF OCTAVES?
Definition
 2^n=fH/fL
Supporting users have an ad free experience!