sia-smaart school applications seminars

2. What are we going to cover? System Alignment Overview Reading the Phase Trace. Our TF Friends: Averaging Coherence Magnitude Thresholding System Alignments: Crossovers, Setting Delays, Subs, etc. What Ever Else You Want . . . .

3. System engineering is managing interactions Acoustically Multiple Drivers, Speakers, Systems Reflections/Acoustics

4. Signal Addition Jean Baptiste Joseph Fourier All complex waves are composed of a combination of simple sine waves of varying amplitudes and frequencies

5. The Big Question

7. System Engineering Key Concept: Interactions are greatest where signals are equal level - Crossover Points

8. System Engineering Key Concept: Interactions are greatest where signals are equal level - Crossover Points Phase determines the interaction Phase Shift (Filters)? Polarity (Wiring)? Delay (Time Alignment)?

9. Arrays

10. Arrays:Point Destination

11. Arrays: Planer

12. Arrays: Point Source

13. Reading the Phase Trace�It�s About Time�

14. Math You Need: T=1/� & �=1/T

15. �Our Friend the Comb Filter�or�Where Did All That Ripple Come From?�

17.

20. Reading the Phase Trace

21. Smaart Measurement Delay

22. Phase Trace Slope Shows Delay

23. Phase Trace Slope Shows Delay

24. Phase Trace Slope Shows Delay

31. Polarity Reversal

32. System Alignment

33. An analyzer is only a tool: YOU make the decisions You decide what to measure. You decide which measurements to use. You decide what the resulting data means. And you decide what to do about it.

34. Any idiot can get squiggly line to appear on the Smaart screen.

35. To use Smaart for system alignment, we must first: Verify that we are making our measurements properly. Verify that it is an appropriate measurement for our purpose.

36. Dual-Channel Measurement Issues: Propagation Time Linearity - Does response change with level? Noise Averaging & Thresholding Coherence

37. Coherence Given as a value between 0 to 1 (0% - 100%)? 100% = Highest Coherence = great data 0% = Lowest Coherence = bogus data

38. Coherence Three causes of bad coherence: Bad measurement Check measurement delay Check measurement signals Check measurement set-up Check equipment

39. Coherence Three causes of bad coherence: Bad measurement Poor Signal to Noise Ratio Turn up measurement level Turn down �noise�

40. Coherence Three causes of bad coherence: Bad measurement Poor Signal to Noise Ratio Poor Direct to Reverb Ratio Move mic closer to source Move source closer to mic Damp reverberance

41. You Are Responsible For Checking Your Measurement Ask yourself, �Does this make sense?� If it doesn�t, check your measurement You are responsible for checking the validity of your measurement � Smaart is responsible for crunching numbers and drawing pretty lines.

42. Transfer Function ModeRecommended Settings

43. Art&System Engineering

44. Art & Engineering Art is the goal Engineering makes the goal possible

45. Art is the goal. Art is a subjective experience. If you don�t know where you�re going, how will you know when you get there? The system needs to fit the goal Your artistic goals set your priorities One size does not fit all. Make the right compromises

46. System Engineering:The Alignment Process Eliminate technical problems Fix wiring errors Patching errors Polarity reversals Grounding/Hum problems Detect / replace bad components Blown drivers Bad amplifier channels Faulty electronics

47. Eliminate technical problems Increase efficiency Gain structure Better dynamic range Good addition through crossovers Maximize power-bandwidth Proper limiter settings / system protection System Engineering:The Alignment Process

48. Eliminate technical problems Increase efficiency Increase consistency Consistent in Level and Tonality Everyone gets the same show Mix translates well to audience System responds to equalization System Engineering:The Alignment Process

49. Eliminate technical problems Increase efficiency Increase consistency Adapt to changing environments Changes in temperature and humidity Changes in acoustics with addition of audience Detection of problems during performance System Engineering:The Alignment Process

50. Eliminate technical problems Increase efficiency Increase consistency Adapt to changing environments Give objective feedback/reinforcement Quantify what you�re hearing Peaks vs dips True center frequency and bandwidth Help for tired ears System Engineering:The Alignment Process

51. System Alignment

52. Systems From single devices to complex combinations of equipment and acoustical environments: Loudspeakers (in an acoustic environment)? Equalizers Consoles Microphones Complete Sound Systems

53. Systems Total system response is the sum of responses of the individual system elements Links in a chain - �weakest link� Align from Individual Combined Systems

54. System Engineering Key Concept: Interactions are greatest where signals are equal level - Crossover Points

55. System Engineering Key Concept: Interactions are greatest where signals are equal level - Crossover Points Phase determines the interaction Phase Shift (Filters)? Polarity (Wiring)? Delay (Time Alignment)?

56. Our goal is to fix our systemnot the trace on the screen.

57. Key Concept: Solve problem at source The closer to the source . . . the more effective the solution.

58. System Engineering Key Concepts: Use the right tool �Every item in your tool box is a hammer . . . except your wood chisels, they�re screwdrivers.�

59. Tools in Order of Use Acoustic Design / Treatment Equipment Choice / Maintenance System Design - �Design to align�

60. Tools in Order of Use Acoustic Design / Treatment Equipment Choice / Maintenance System Design - �Design to align� Level Delay

61. Tools in Order of Use Acoustic Design / Treatment Equipment Choice / Maintenance System Design - �Design to align� Level Delay And lastly . . . EQ

62. Problem

63. Solution(s)?

64. Setting Delays

65. Setting Delays

66. 1 ms : 1 kHz : 1 ft

67. Example: Delay vs. Physical Positioning

68. Example: Delay vs. Physical Positioning

69. System engineering . . .Is optimizing your compromises It�s all give and take.

70. System Engineering&The Serenity Prayer . . . Grant me the SerenityTo accept the things I cannot change�

71. System Example: