How does a line array differ from a stack of speakers?

[akio123008]

Line array speaker systems are becoming increasingly popular. I've done some research on this, and it turns out a line array is simply a bunch of identical speakers stacked on top of each other, fed in phase, with the drivers being as close to each other as possible for higher frequencies. But is there nothing else to it? could a line array be made from a stack of off the shelf speakers that are the same?

 

Thanks in advance for any replies!

[ricksteendam1]

6 minutes ago, akio123008 said:

Line array speaker systems are becoming increasingly popular. I've done some research on this, and it turns out a line array is simply a bunch of identical speakers stacked on top of each other, fed in phase, with the drivers being as close to each other as possible for higher frequencies. But is there nothing else to it? could a line array be made from a stack of off the shelf speakers that are the same?

 

Thanks in advance for any replies!

its used to spread the sound more evenly but I won't see a consumer use for it.

[Ahoy Hoy]

7 hours ago, akio123008 said:

Line array speaker systems are becoming increasingly popular. I've done some research on this, and it turns out a line array is simply a bunch of identical speakers stacked on top of each other, fed in phase, with the drivers being as close to each other as possible for higher frequencies. But is there nothing else to it? could a line array be made from a stack of off the shelf speakers that are the same?

 

Thanks in advance for any replies!

Line arrays have a drop of 3dB every time you double the distance which is half of what a point source is which drops audio at 6dB every time you double the distance. So they are louder at longer distances. Which is why they are commonly used at music festivals etc since there such long distances.

[akio123008]

I'm aware of all that, I've done quite a bit of reading online. But I'm wondering how these systems that are officially called line arrays, are different from a simle stack of identical speakers. I mean, a stack of identical speakers should in theory be the same as one of those suspended line arrays right?

[Ahoy Hoy]

7 minutes ago, akio123008 said:

I'm aware of all that, I've done quite a bit of reading online. But I'm wondering how these systems that are officially called line arrays, are different from a simle stack of identical speakers. I mean, a stack of identical speakers should in theory be the same as one of those suspended line arrays right?

Well to get a speaker to couple together it has to be closer then 1/4 of the wavelength.  So in the case of a low frequncy like 170Hz the wavelength is 2 meters so the speakers cant be further then 50cms away, which is not too had to do. But at a high frequncy such as 13500Hz the wavelength is 2 inchs so the speakers have to be less then 1/2 a inch. Thats not easily done without making custom cabinets. So using a standard speaker and just stacking it on top, the mid lows be alright, but any high frequncies wont couple and will actually be quieter as it will probably cause cancellation in some areas.

http://www.mcsquared.com/wavelength.htm
Find the frequncy response of your speakers and use the website above to calculate the wavelength and work out how close the speakers will have to be. I suspect unless you've got sub woofers and separate mid drivers you will struggle to get the speaker in a close enough space to couple. 

[akio123008]

Oh now I get it. I didn't even think of that. The drivers need to be really close to each other, which is difficult when using standard speaker cabinets. That makes sense. Thanks!

[Ahoy Hoy]

1 hour ago, akio123008 said:

Oh now I get it. I didn't even think of that. The drivers need to be really close to each other, which is difficult when using standard speaker cabinets. That makes sense. Thanks!

its why line arrays commonly have one mid driver the width of the speaker, yet the cabinet has multiple tweeters to get them close enough.