How To Mix Live Music Chapter 9 - EQ for Outputs — Transcript

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1. 0:07Thanks for joining me again,
2. 0:09for chapter 9 in the series “How to Mix Live Music”.
3. 0:14This time, we will be EQ-ing our outputs:
4. 0:17that is, the speakers for the audience and for the performers on stage.
5. 0:23If you get this right first,
6. 0:25it's going to be easier to EQ all the input channels.
7. 0:30Taking time to work on the outputs first
8. 0:33will save time when working on the inputs later!
9. 0:37The sound you hear from a loud-speaker in a room
10. 0:41will vary depending on its position and your position.
11. 0:46It will also vary depending on the size and shape of the room,
12. 0:51or the outside environment.
13. 0:54You may need to compensate with EQ to obtain the best sound.
14. 1:00The TF3 digital mixer has a parametric EQ
15. 1:03available on all its output channels: Stereo Masters, Aux and Matrix.
16. 1:10This is really useful for such situations.
17. 1:14However, the MGP32X doesn’t have any parametric EQ for its outputs.
18. 1:20Though it does have a Graphic EQ available for the Stereo Master,
19. 1:26which is found in its digital display section.
20. 1:30So, to partner with MGP32X mixers,
21. 1:35I recommend to use powered speakers
22. 1:38that have a choice of frequency curves available.
23. 1:42Such as the Yamaha DXR range, with its “D-CONTOUR” function.
24. 1:49Test which mode sounds best in the room.
25. 1:53The MONITOR mode is useful,
26. 1:55as it reduces low frequencies which otherwise would be boosted too much
27. 2:00due to the proximity of the speaker to the floor.
28. 2:04The HPF, high pass filter, is useful in combination with a Sub-Woofer,
29. 2:10to allow the low frequencies from the Sub to punch through effectively.
30. 2:16To test the sound, play your favorite music tracks through the system,
31. 2:21at the sound levels expected for the performance.
32. 2:24Remember the gain structure we set up in chapter 6.
33. 2:30If you are using a TF-series mixer,
34. 2:32and you don’t have time to make such a sound check,
35. 2:36then there are some useful output EQ presets you could try:
36. 2:40select the output, open the EQ window, and press the Preset button.
37. 2:49You can find settings for “Small Room”, ‘Large Room” and “Outside”.
38. 2:54If you do have time to make your own adjustments, then here are some tips:
39. 3:00use the EQ mainly for gain reduction rather than boosting,
40. 3:05to reduce the risk of feedback.
41. 3:08If you think the sound needs more low frequency punch,
42. 3:12rather than increasing the low EQ band, try reducing the high.
43. 3:18If the vocal is not prominent enough,
44. 3:21rather than increasing the mid frequencies,
45. 3:24try reducing both low and high bands.
46. 3:29This task is all about getting a balanced sound.
47. 3:34Play several different styles of track to check the sound
48. 3:37and confirm your settings.
49. 3:40Now we’re going to consider the use of a Graphic EQ.
50. 3:44A traditional analog unit looks like this, with up to 31 short sliders,
51. 3:49each one adjusting a different band of frequencies.
52. 3:54Both MGP and TF mixers have digital Graphic EQ available.
53. 4:01The TF on all mono Aux outputs for stage monitors, and the Stereo Master.
54. 4:11In hi-fi and car audio systems,
55. 4:13the Graphic EQ has often been used for shaping the sound:
56. 4:17it is more visual and intuitive than a parametric EQ.
57. 4:22However, we are going to use the Graphic EQ in live sound
58. 4:26for reducing the chance of feedback squeals and howls.
59. 4:32Let’s take a look at the TF first, because it's easier to use.
60. 4:38Select the Stereo Master channel and open its Graphic EQ window.
61. 4:44Then you can scroll from left to right to see all the 31 bands.
62. 4:50It is so useful to see a spectrum analysis along the top,
63. 4:54which shows the signal level at each frequency.
64. 4:57It can clearly show where feedback is occurring!
65. 5:02Our aim now is to deliberately create audio feedback,
66. 5:07and then eliminate it with the Graphic EQ.
67. 5:12First, switch off the playback music
68. 5:15and switch on the channels for the mics on stage,
69. 5:22but we are keeping the stage monitor speakers off.
70. 5:27Push up the faders, to allow sound through the PA speakers.
71. 5:32Then keep on raising the faders until some feedback squeal occurs.
72. 5:38Then locate the frequency on the spectrum analyzer,
73. 5:43and bring the Graphic EQ fader down about 5 dB.
74. 5:49Each fader creates a narrow bell shaped curve,
75. 5:52reducing the gain around its stated center frequency.
76. 5:57Raise the faders further to create feedback again.
77. 6:01It could be at a different frequency,
78. 6:04or it could be the same one again.
79. 6:07Reduce the Graphic EQ band to make it safe.
80. 6:11Do this several times, to catch the most dangerous frequencies for feedback.
81. 6:17Another method is to raise each Graphic EQ band about +5, one band at a time.
82. 6:27If it doesn’t cause feedback, return it to zero point.
83. 6:32If it does cause feedback, take it down to about -3 to -5.
84. 6:39If you find more than six or seven feedback frequencies,
85. 6:43it could mean the loudspeakers are too close to the microphones,
86. 6:47so consider re-positioning them to a safer distance.
87. 6:52Or the sound might just be too loud for the acoustics of the room!
88. 6:57Well, at least the presence of an audience later in the day
89. 7:01will usually help to absorb and diffuse the sound a bit more
90. 7:05to reduce the risk of feedback.
91. 7:10Now let’s take a look at the MGP32X.
92. 7:14On the Stereo Master channel, there are two choices for Graphic EQ type.
93. 7:2014-Band Graphic EQ
94. 7:22is more suitable for shaping the sound character to suit the venue.
95. 7:27Use it if there is no problem with feedback.
96. 7:30However, it is best to use “Flex-9 GEQ” to deal with feedback,
97. 7:36because it has narrower frequency bands:
98. 7:40there are 31 bands, of which any 9 can be adjusted.
99. 7:45Here’s how to use it:
100. 7:47Bring the faders up to the point where feedback is almost starting.
101. 7:53Then take a look at the Graphic EQ “SWEEP L/R” page on the screen.
102. 8:00Dial in a 3 dB offset
103. 8:04and scroll through the frequencies, spending a couple of seconds on each one.
104. 8:10If a screech or howl is heard,
105. 8:13reduce that band to -3 dB and press the OFFSET knob to set the level.
106. 8:20Then continue through all the frequencies.
107. 8:23And repeat using an offset of +6 dB,
108. 8:26cutting the feedback frequencies as you go,
109. 8:29until you have either dealt with 9 bands,
110. 8:32or reduced just a few of the most troublesome bands.
111. 8:37Next, bring the master fader back down to a safe level,
112. 8:41and switch on the stage monitors.
113. 8:44Unfortunately the MGP mixer doesn’t have any EQ facility on its Aux outputs:
114. 8:51you would need some stand-alone Graphic EQ units for that.
115. 8:54But TF-series consoles have Graphic EQ available.
116. 8:59So let’s fight the feedback on stage, using the same method.
117. 9:04Keeping the mics active,
118. 9:05raise the output level of the Aux until feedback occurs.
119. 9:11Find the feedback frequency, and cut it a bit.
120. 9:16Raise the level, find the next frequency, and so on.
121. 9:21If you are short of time, you can set this up using one monitor speaker,
122. 9:26then copy & paste the Graphic EQ settings to the other Aux channels,
123. 9:30using the menu button on the bottom-right side of the touch-screen.
124. 9:36And remember TF series has an iPad app
125. 9:39which lets you edit the Graphic EQ while walking around the stage!
126. 9:45Now some musicians choose to use in-ear monitors on stage,
127. 9:49and there is one big advantage: no feedback!
128. 9:54But they will generally require an additional EQ
129. 9:58to make a more pleasant sound for the performer.
130. 10:01Especially the singers,
131. 10:02as they will hear their own voice partly amplified through the ear-phones
132. 10:06and partly through vibrations from throat to ear.
133. 10:11Thankfully, the TF has various presets for that too,
134. 10:15on its Stereo Aux outputs.
135. 10:18Select the channel, and recall the preset!
136. 10:26Notice how these EQ curves have a couple of small peaks:
137. 10:30to increase low frequency punch, and to improve vocal clarity.
138. 10:37You can increase or decrease their effect
139. 10:39by using the TF console’s special “1-knob” “Intensity” mode.
140. 10:46See the peaks grow or shrink as you adjust!
141. 10:52We’ll talk more about mixing for in-ear monitors in a later episode.
142. 10:58But after all that EQ-ing,
143. 11:00we should have a good balanced sound at the outputs.
144. 11:04Now we’re ready to start applying EQ to all the input sources.
145. 11:10Different instruments and voices require different techniques.
146. 11:14In the next chapter, I’ll fill you in about EQ-ing drums!
147. 11:19Join me again then!