State Tech Training Spring 2014

1. State Tech Training Spring 2014

2. Welcome to State-Aud-Con “State Tech Audio Concepts”

3. State Tech Plaza

4. Faces to know – Pro Staff Jen Lichty Angie Courteau Mark Venhuizen

5. Faces to know – more Pro Staff Keith Skogstad Lindsie Bartley Jenn Novotny

6. Coordinators Kate VanHeel Brian Eiesland Nathan Rausch Sidney Smith

7. Rigs • Sound C (with or without subs) • Extremes • EAW • JBL • DJ Rig • House Sound (VBR, Campanile, Wills, Einstein)

8. Types of events • Speeches • Panel Discussions • PowerPoint presentations • Stage Load-ins • International Nights • Banquets • Dances • Bands/Concerts

9. State Tech Acronyms & TermsMost common • FOH – Front of House • VBR – Volstorff Ballroom • Media – Equipment rack with media gear • FX – Equipment rack with effects processors • EQ – Equalizer • Comp/Gate – compressor/gate combo unit • Mic – microphone • EAW – Eastern Acoustic Works…our monitor and FOH gear • Sound C – small/medium format sound system • Extreme – very small format sound system • DI – direct input (unbalanced signal to balanced signal) • PCDI – personal computer direct input

10. Locations to Know • VBR - Volstorff Ballroom • Camp Hope – VBR Booth • 135 Hallway/ North Hallway • Loading Dock/Freight Elevator • Data Closet • 150 Office Suite • Tech Plaza • 001 • Market Stage • Campanile/ Hobo Day Gallery • Lewis and Clark • Jacks Place • Sylvan Green • Frost Arena • Animal Science Arena • Coughlin Alumni Stadium • PAC - Performing Arts Center • Peterson Recital Hall(Lincoln) • The Barn VS DePuy • Storage Unit

11. Basic components of Sound Reinforcement • Sources – Microphones, iPods, Guitar(DI), Etc. • Mixer (Sound Board) – Analog, Digital • Signal Processor – EQ, Delay, Compression, Limiting • Amplifier • Loudspeakers – Active/Passive • Acoustical Environment – Noise/Reflections • Audience – Sufficient soundlevel (easy) andclarity (hard).

12. General Setup Goals (1) Place loudspeakers for even coverage --Aim for back row --Minimized coverage overlap (2) Use Appropriate Interconnect practices --Use Balanced Cables when possible --Correct Gauge Cable for Loud Speakers --Use DI’s for Long distance runs (6’+) • Establish System Gain Structure -- Set Mixer at 0dB or “Unity” --Set Amplifiers to Desired Volume.

13. General Setup Goals Cont. (4) Verify setup with iPod or CD Tracks --Music AND SPEECH -- Walk the audience areas and LISTEN --This is your goal for the performance. (5) Connect mics and set levels --Fader at “zero” or “unity” --adjust gain to “unity” --Watch for overload

14. A Quick note of “unity” • Unity is in most cases is “Zero” however “Zero” means a variety of things in different cases. Most often it is 0dB. dB is only a reference. dB SPL, dBu, dBFS actually mean something. However, 0dB SPL is inaudible, 0dBu is generally mix position, and 0dbFS is just under clipping the system.

15. General Setup Goals Cont. (6) Set monitor levels --Must be at least 10db below mains in house (half loudness) --Set house first, leave house up, then set monitors (7) Details = Ear Candy --If it does not sound good by now go back to step 1 --EQ Main loud speakers --Channel EQ, Compression, Effects --Address micing problems with placement/swapping --Refine by subtraction – Simplify!

16. Back to dB What is dB? A Reference! Relative: Turn it up 3dB. Absolute: Set it for 80 db SPL. Even better: Set it for 80db SPL A weighted Slow

17. Relative Levels The Decibel Perceived Change dB Change Power Ratio No change0 dB 1x Perception Threshold 1 dB 1.26x Minimum practical change 3 dB 2.0x Goal for system changes 6 dB 4x Twice loudness 10 dB 10x 20 db 20 dB 100x 30 dB 30 dB 1000x 40 dB 40 dB 10,000x What you need always depends on what you start with!

18. Absolute SPL • Sound level change of 1 or 2 dB is barely noticeable • Ears need 10 dB SPL to perceive sound as twice as loud • 100 watt amp sounds twice as loud as 10 watt amp using same speakers & same distance • Switching from 100 watt amp to 200 watt amp = 3 dB increase • 1000 watt amp doubles perceived volume from 100 watt amp

19. Absolute Sound Pressure Levels (From OSHA, SPL A-weighted slow)

20. Absolute Sound Pressure Levels (From OSHA, SPL A-weighted slow)

21. Absolute Sound Pressure Levels (From OSHA, SPL A-weighted slow)

22. Other SPL Factors • For a given power to a loudspeaker, perceived loudness depends on: • 1) Distance between listener & loudspeaker • 2) Audio frequency • 3) Room acoustics • 4) How well listener’s ears work • 5) Loudspeaker efficiency

23. Audio Frequencies - Hearing • Human hearing ranges from about 20 Hz to 20,000 Hz • Speech range from about 100 Hz to 4 kHz • Music fundamentals fall between 40 Hz & 15 kHz

24. Audio Frequencies - Harmonics • Audio waveforms contain harmonics or overtones

25. Audio Frequencies • Octave - interval between 2 frequencies having 2:1 ratio • Each doubling of fundamental is an octave • Audio frequencies cover 10 octaves • Center for articulation located in the 2kHz Octave Articulation

26. State Tech FOH Sound System Overview

27. Interconnects Unbalanced Pros: Cheap Good fidelity Cons: Sensitive to any input voltage No noise immunity Prerequisites: Short cables (<1m) ¼” TS Connector RCA (Phono) Plug

28. Interconnects Balanced Pros: Good Fidelity Noise immunity Polarity easily reversed Cons: Polarity easily reversed More Expensive than Unbalanced XLR Connector ¼” TRS Connector

29. Interconnects Sound System

30. Interconnects Other

31. The Channel Strip

32. The Channel Strip - Signal Flow

33. Microphone Placement Tips

34. Mike’s Micing Techniques • For many applications, keep the microphone as close to the source as possible Mike Hi, I’m Mike!!! Mic -Make sure customer speaks into the microphone with sufficient volume AND clarity, and at a very small distance from the microphone

35. Mike’s Micing Techniques (cont.) • For guitar and bass cabs, place the mic slightly off-center of the cone and as close to the grill as possible without touching the grill.

36. Mike’s Miking Techniques (cont.)

37. Mike’s Miking Techniques (cont.)

38. Microphone Specs 1. Sensitivity The signal level post gain should be sufficient to produce a “meter zero” indication on the main or solo meter. The factors that affect this are: 1. Mic sensitivity 2. Source level 3. Mic-to-source distance 4. Gain/Trim setting  2. Pattern Polar patterns can be used to reject unwanted sound

39. Microphone Specs (cont) 3. Distance Close-micing produces improved signal-to-noise ratio and direct to reflected ratio 4. Iteration The 3 to 1 rule Only one mic should be used for each program source (generally). Large sources may require multiple mics. 5. Polarity

40. Microphone Types Dynamic General Features -Passive (No External power) -Ultra Reliable -Low sensitivity -Robust construction -High SPL • Tech Microphones include Beta 58, SM 58, SM57, Beta 52, Beta 56, ATM 25

41. Microphone Types Condenser General Features -Active (Requires power source AKA phantom power) -Wide Bandwidth -High Sensitivity -On-board filters (sometimes) • Tech Microphones include SM81, Beta 87, Beta 98, Podium Mics

42. Phase Cancellation • Happens when a single source is 180degress out of phase. (can happen with only 1 mic!)

43. Microphone Notes -Use dynamic mics when possible (more reliable, less loading on mixer, no pops) -Mic proximity affects the sound. The closer the better! -Avoid lapel microphones when possible…AT ALL COSTS!!! -Compared to lapel mics, head worn mics sound better, provide more gain, and have less interaction with other mics and reflective sources. -Use wired mics instead of wireless when possible Phantom Power Phantom power is a DC power source, that is originated at the mixer, and feeds the microphone through a standard mic cable (XLR). -Current limited by mixer design -Causes “pops” if interrupted -Requires shield connection in cable -48VDC is “standard” but other voltages can work -Turn off if not needed -DON’T supply to tape decks, ribbon mics, etc. -Turn off prior to patching mics -Needed for active DI’s, unless DI is supplied with a battery

44. Mixer Gain Structure 1. During the sound check, adjust each channel trim to produce a “zero” reading on the main meter. This is the minimal level that will be needed from a single channel. Always -Do this before you set stage monitor levels. -Don’t readjust trims if you are running the monitors

45. For a Quick Setup, Set all the faders to “Unity” and do a quick mix with the channel trims.

46. Inserts • Line level signal processors can be “inserted” into the signal chain for individual mixer channels if needed Insert Processors: Notch Filters, Equalizers, Compressors, Effects 1. Set external device to unity 2. Keep Cables Short 3. Use Sparingly

47. Dynamic Range Control

48. Our Compressors To make a compressor a limiter simply set the ratio to infinity to 1. General Rule; If you can hear the limiter, you’re using too much. If you can’t hear the compression, you’re using too little.

49. Graphic Equalizers • Graphic Equalizer. A multi-band variable equalizer using slide controls as the amplitude adjustable elements. Named for the positions of the sliders "graphing" the resulting frequency response of the equalizer. Only found on active designs. Both center frequency and bandwidth are fixed for each band.

50. Equalizer effects