Microphone Feedback: Difference between revisions

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* If you are using vocal effects like reverb, chorus or delay, turn them off until you can get sufficient [[Gain Before Feedback|gain before feedback]] to get performance level volume. Then add the effects back into the signal chain (one at a time) so you can be aware of the individual impacts that each effect is having on feedback.

* Get close to the microphone. No other technique has a big an impact on feedback. Each halving of distance is approximately another 6 dB of [[gain before feedback]]. This means that the difference between working a microphone at 2 inches, and 1/4 inch is 18 dB, which is more than twice as loud.

* '''Get close to the microphone''' when you want to be loud. No other technique has a big an impact on feedback. Each halving of distance is approximately another 6 dB of [[Gain Before Feedback|gain before feedback]]. This relationship in physics is known as the [[Inverse Square Law]]. This means that the difference between working a microphone at 2 inches, and 1/4 inch is 18 dB, which is more than twice as loud. While good mic technique often involves "working" the microphone at different distances, singers must be mindful of the fact that small changes in distance from the mouth result in very dramatic changes in sound level.

[[Image:Ferrin_eat_mic.jpg|Charlie Ferrin at Bose: Nov. 9, 2007]]

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* Use the high-frequency tone control for the microphone channel carefully. Feedback could occur when this is set too high.

[~~stopped editing here~~]

* Wherever possible, acoustic instruments should use pickups instead of microphones. Pickup systems provide much higher [[Gain Before Feedback|gain before feedback]] than microphones.

* ~~Upgrade your power stand~~ to ~~newer software that offer a high gain preset. see: Software Upgrading (This covers firmware update and Version 2~~.~~0 [[Presets/Model I and Classic|Presets]])~~

=== Techniques specific to the {{L1 family}} ===

* All players should be playing / singing through the {{L1}} closest to them.

~~From the Official Product FAQs <ref>[http://www.bose.com/controller?event=VIEW_STATIC_PAGE_EVENT&url=/musicians/support/product_faqs.jsp&ck=0#question40 Official Product FAQs]</ref>.~~

~~Techniques that control feedback with a conventional system help with the Personalized Amplification System™ approach also.~~

== Other Resources ==

~~== Other general notes ==~~

* [http://www.shure.com/stellent/groups/public/@gms_gmi_web_ug/documents/web_resource/us_pro_mics_for_music_sound_ea.pdf Shure® article on mic technique] Shure Educational Publication 2006 39 pages - pdf format

* All players should be playing / singing through the L1™ System closest to them

* Wherever possible "acoustic" instruments should use pickups instead of microphones. This is important because many players find it a struggle to keep a consistent and close distance between the microphone and their instrument. Also, an instrument can be a source of feedback as it resonates with the amplified sound.

* Another (low priority) design guide-line could be to keep open microphones as far apart as possible. Neighboring systems with open microphones can mutually decrease gain-before-feedback

~~=== Handling the Microphone ===~~

~~shure.com notes <ref>[http://www.shure.com/shurenotes/how_june2004/default.asp Miking Live Vocals - from shure.com]</ref>~~

Seems like a pretty natural thing, doesn't it? But how your vocalists handle the microphone has a major effect on the resulting sound. It may look great, but your tech team won't get the sound they want when your soloist holds a microphone an arm's length from her mouth.

~~=== Why? ===~~

The first reason is the inverse square law. If you hold your mic a half-inch from your lips it receives a given amount of sound energy from your voice. Move it twice as far-one inch-and it receives one-fourth as much energy. That extra half -inch takes away three-quarters of the efficiency of your sound system. While good mic technique involves "working" the microphone, singers that fully extend their arms when reaching for that climax, are usually doing it for dramatic effect. Small changes in distance from the mouth can result in very dramatic changes in sound level.

Second: When you move the microphone away from your lips, you must turn up the microphone level at the mixer to be heard, and more unwanted sound enters the mic. When sound from a monitor speaker enters the microphone , it instantly becomes the earsplitting screech we know as feedback. Keeping the microphone close to your mouth minimizes feedback.

~~See the whole article: [http://www.shure.com/shurenotes/how_june2004/default.asp Miking Live Vocals]~~

~~== Other References ==~~

* [http://www.shure.com/stellent/groups/public/@gms_gmi_web_ug/documents/web_resource/us_pro_mics_for_music_sound_ea.pdf Microphone Techniques for Live Sound Reinforcement] Shure Educational Publication 2006 39 pages - pdf format

~~- [http://bose.infopop.cc/eve/forums/a/ga/ul/5711082304/us_pro_mics_for_music_sound_ea.pdf alternate source for above]~~

~~[[User:ST|ST]] 15:46, 22 August 2006 (GMT-7)~~

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@@ Line 12: / Line 12: @@
 * If you are using vocal effects like reverb, chorus or delay, turn them off until you can get sufficient [[Gain Before Feedback|gain before feedback]] to get performance level volume. Then add the effects back into the signal chain (one at a time) so you can be aware of the individual impacts that each effect is having on feedback.
-* Get close to the microphone. No other technique has a big an impact on feedback. Each halving of distance is approximately another 6 dB of [[gain before feedback]]. This means that the difference between working a microphone at 2 inches, and 1/4 inch is 18 dB, which is more than twice as loud.
+* '''Get close to the microphone''' when you want to be loud. No other technique has a big an impact on feedback. Each halving of distance is approximately another 6 dB of [[Gain Before Feedback|gain before feedback]]. This relationship in physics is known as the [[Inverse Square Law]]. This means that the difference between working a microphone at 2 inches, and 1/4 inch is 18 dB, which is more than twice as loud. While good mic technique often involves "working" the microphone at different distances, singers must be mindful of the fact that small changes in distance from the mouth result in very dramatic changes in sound level.
 [[Image:Ferrin_eat_mic.jpg|Charlie Ferrin at Bose: Nov. 9, 2007]]
@@ Line 26: / Line 26: @@
 * Use the high-frequency tone control for the microphone channel carefully. Feedback could occur when this is set too high.
-[stopped editing here]
+* Wherever possible, acoustic instruments should use pickups instead of microphones.  Pickup systems provide much higher [[Gain Before Feedback|gain before feedback]] than microphones.
-* Upgrade your power stand to newer software that offer a high gain preset. see: Software Upgrading (This covers firmware update and Version 2.0 [[Presets/Model I and Classic|Presets]])
+=== Techniques specific to the {{L1 family}} ===
+* All players should be playing / singing through the {{L1}} closest to them.
-From  the Official Product FAQs <ref>[http://www.bose.com/controller?event=VIEW_STATIC_PAGE_EVENT&url=/musicians/support/product_faqs.jsp&ck=0#question40 Official Product FAQs]</ref>.
-Techniques that control feedback with a conventional system help with the Personalized Amplification System™ approach also.
+== Other Resources ==
-== Other general notes ==
+* [http://www.shure.com/stellent/groups/public/@gms_gmi_web_ug/documents/web_resource/us_pro_mics_for_music_sound_ea.pdf Shure® article on mic technique] Shure Educational Publication 2006 39 pages - pdf format
-* All players should be playing / singing through the L1™ System closest to them
-* Wherever possible "acoustic" instruments should use pickups instead of microphones.   This is important because many players find it a struggle to keep a consistent and close distance between the microphone and their instrument. Also, an instrument can be a source of feedback as it resonates with the amplified sound.
-* Another (low priority) design guide-line could be to keep open microphones as far apart as possible. Neighboring systems with open microphones can mutually decrease gain-before-feedback
-=== Handling the Microphone ===
-shure.com notes <ref>[http://www.shure.com/shurenotes/how_june2004/default.asp Miking Live Vocals - from shure.com]</ref>
-Seems like a pretty natural thing, doesn't it? But how your vocalists handle the microphone has a major effect on the resulting sound. It may look great, but your tech team won't get the sound they want when your soloist holds a microphone an arm's length from her mouth.
-=== Why? ===
-The first reason is the inverse square law. If you hold your mic a half-inch from your lips it receives a given amount of sound energy from your voice. Move it twice as far-one inch-and it receives one-fourth as much energy. That extra half -inch takes away three-quarters of the efficiency of your sound system. While good mic technique involves "working" the microphone, singers that fully extend their arms when reaching for that climax, are usually doing it for dramatic effect. Small changes in distance from the mouth can result in very dramatic changes in sound level.
-Second: When you move the microphone away from your lips, you must turn up the microphone level at the mixer to be heard, and more unwanted sound enters the mic. When sound from a monitor speaker enters the microphone , it instantly becomes the earsplitting screech we know as feedback. Keeping the microphone close to your mouth minimizes feedback.
-See the whole article: [http://www.shure.com/shurenotes/how_june2004/default.asp Miking Live Vocals]
-== Other References ==
-* [http://www.shure.com/stellent/groups/public/@gms_gmi_web_ug/documents/web_resource/us_pro_mics_for_music_sound_ea.pdf Microphone Techniques for Live Sound Reinforcement] Shure Educational Publication 2006 39 pages - pdf format
-- [http://bose.infopop.cc/eve/forums/a/ga/ul/5711082304/us_pro_mics_for_music_sound_ea.pdf  alternate source for above]
-[[User:ST|ST]] 15:46, 22 August 2006 (GMT-7)
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