In an effort to almost continue what I was talking about last week, I have opted to further research how to properly set up a loudspeaker array for the maximum amount of even coverage as well as reducing phase issues and as much as possible. For this, It is necessary to know how to reduce the amount of lobes and nulls within a loudspeaker system.
The word lobe, when used in the context of audio, is often defined as a maximum of sound pressure that occurs within a sound field caused by the loudspeaker array. The author of the article, Pat Brown, describes them as "'fingers' of sound pressure 'maximums' in the three-dimensional space..."(Brown 3) Lobes can be problematic as most microphones set within a lobe will almost undoubtedly feedback. Nulls, on the other hand are the exact opposite. Nulls could be thought of as sound pressure minimums within a speaker array, which can cause a lose of speech intelligibility within the audience.
As Pat Brown has detailed in the article, There are many possible "solutions" one can take to combat these problems, such as comb filtering, with some being much better ideas than others. One could use an analyzer resolution to reduce the comb filtering and adjust the equalizer. Though this may seem like a quick fix, them problem has been temporarily masked and has not truly been fixed. Another option would be to notch out certain problem frequencies, although this could be detrimental to the sound quality because you are removing necessary frequencies. One could simply be to conclude that the audience won't even notice the filtering and do nothing, but that truly doesn't solve anything. The only real way to solve the problem is to address the spacing of the loudspeaker array.
Comb filtering and phasing is a timing issue, so by spacing two loudspeakers that are close together further apart, the amount of lobes and nulls created will be reduced.
Take note that it is also possible to reduce these lobes and nulls by using quality loudspeakers. Some loudspeakers are built to have features, such as horn-loaded components and aggressive pattern control, that help reduce interaction with other loudspeakers, which will reduce a lot of comb filtering and phasing issues. Though larger speakers seem to be better, if size is an issue in a particular venue, one can use smaller speakers in greater number set up closer to the audience, such as an exploded array (Brown 3).
To fully understand this, I had to further research what an exploded array is. Though I wasn't able to find an exact definition of explanation from many images I could find I gather that it involves separating the components in a loudspeaker from each other so that the highs and the mids are not coming from the same speaker enclosure.
Works Cited
Brown, Pat. "Proper Loudspeaker Placement: How To Avoid Lobes and Nulls." ProSoundWeb. 13 Jun 2012: 3. Web. 17 Jan. 2013. <http://www.prosoundweb.com/article/lobes_and_nulls/>.
The word lobe, when used in the context of audio, is often defined as a maximum of sound pressure that occurs within a sound field caused by the loudspeaker array. The author of the article, Pat Brown, describes them as "'fingers' of sound pressure 'maximums' in the three-dimensional space..."(Brown 3) Lobes can be problematic as most microphones set within a lobe will almost undoubtedly feedback. Nulls, on the other hand are the exact opposite. Nulls could be thought of as sound pressure minimums within a speaker array, which can cause a lose of speech intelligibility within the audience.
As Pat Brown has detailed in the article, There are many possible "solutions" one can take to combat these problems, such as comb filtering, with some being much better ideas than others. One could use an analyzer resolution to reduce the comb filtering and adjust the equalizer. Though this may seem like a quick fix, them problem has been temporarily masked and has not truly been fixed. Another option would be to notch out certain problem frequencies, although this could be detrimental to the sound quality because you are removing necessary frequencies. One could simply be to conclude that the audience won't even notice the filtering and do nothing, but that truly doesn't solve anything. The only real way to solve the problem is to address the spacing of the loudspeaker array.
Comb filtering and phasing is a timing issue, so by spacing two loudspeakers that are close together further apart, the amount of lobes and nulls created will be reduced.
Take note that it is also possible to reduce these lobes and nulls by using quality loudspeakers. Some loudspeakers are built to have features, such as horn-loaded components and aggressive pattern control, that help reduce interaction with other loudspeakers, which will reduce a lot of comb filtering and phasing issues. Though larger speakers seem to be better, if size is an issue in a particular venue, one can use smaller speakers in greater number set up closer to the audience, such as an exploded array (Brown 3).
To fully understand this, I had to further research what an exploded array is. Though I wasn't able to find an exact definition of explanation from many images I could find I gather that it involves separating the components in a loudspeaker from each other so that the highs and the mids are not coming from the same speaker enclosure.
Works Cited
Brown, Pat. "Proper Loudspeaker Placement: How To Avoid Lobes and Nulls." ProSoundWeb. 13 Jun 2012: 3. Web. 17 Jan. 2013. <http://www.prosoundweb.com/article/lobes_and_nulls/>.
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