Line Array Reading List

[airborne]

Hi !

I have designed / built speakers / systems before, but i have never built Line Arrays.

After moving from NYC apartment to NJ house i needed new speakers because my old ones were too small and my original idea was to go with horns for higher output ...

I did a lot of reading ( and a lot of modeling in HornResp ) and learned a lot about horns to the point where i felt like i really understood them ... unfortunately understanding horns made me realize i will probably be better off with a Line Array.

So now i want to do for Line Arrays what i did for horns - read enough quality material to the point where i really understand them ( if i can model them in some free software even better ! ) ...

What should i read ?

I found this paper:

https://jblpro.com/en/site_elements/aes-journal-article-analysis-of-line-arrays

and hope to read it maybe tomorrow after i get some sleep ...

the JBL paper on compression drivers really helped me understand them ... so i hope this JBL paper on line arrays will be good too ...

but what else should i read ?

i am looking to gain a deep level of understanding that will allow me to calculate SPL output at various frequencies because Line Arrays are very expensive and i want to make sure i don't waste money on getting louder drivers than i really need to get the job done, but whereas with point source calculating SPL at listening position is straightforward with Line Arrays it is not ...

i actually already designed the system but i used a lot of assumptions and it would be a very expensive mistake if those assumptions end up being wrong ...

thanks in advance !

PS: the name i came up with for this forum comes from this driver:

One moment, please...

which i am hoping to use as the tweeter in the line array.

yes i know it's a relabeled Hygeia but "airborne" just sounds better

 

[Ericglo]

Why do you want a line array? Have you heard one?

Read @fluid and @Wesayso posts on this forum and diyaudio.

Google Jim Griffin line array. He wrote a paper.

If you are going to do a line array, then it should be floor to ceiling. If you don't want to do that then consider a CBT. The aforementioned Jim went that route. Google Don Keele

There is also some good info in the threads myself and ppataki started about MCLA. It is a corner line array.

 

[D!sco]

+1 on CBTs or Murphy Corner semi infinite arrays. Line arrays are great for SPL and range but sacrifice directivity. You could also look into line sources, with high quality tweeter/midranges in the center to reduce cancellation. I know GR Research, despite their reputation, has a good video outlining the differences and benefits

 

[airborne]

Why do you want a line array? Have you heard one?

Read @fluid and @Wesayso posts on this forum and diyaudio.

Google Jim Griffin line array. He wrote a paper.

If you are going to do a line array, then it should be floor to ceiling. If you don't want to do that then consider a CBT. The aforementioned Jim went that route. Google Don Keele

There is also some good info in the threads myself and ppataki started about MCLA. It is a corner line array.

haven't heard line arrays except the ones at rock concerts and martin logan electrostatics but obviously both are very far from the type of line array i'm trying to build so no i don't know what they sound like ...

i'm in NJ if you have any idea where i can listen to some it would be nice ...

as for why i want line array - loudness

i am willing to sacrifice a little bit of sound quality for a lot of loudness ...

i already have plenty of good sounding speakers but none of them loud enough for my taste ... and the speakers i actually use are COMPLETELY BLOWN and sound like TRASH but i use them because they're the loudest speakers i have ( they're PA speakers ) ...

just came to realize i prefer the sound of PA speakers to that of audiophile speakers because they are simply punchier at any given price point ... you need a $20,000 audiophile speaker to match the punch of a $500 PA speaker

so i figured it's a perfect opportunity for me to combine some properties of PA speakers and audiophile speakers by building a line array out of AMT ribbons on the top and PA woofers on the bottom ...

i was inspired to try this by Beyma producing an AMT line array driver which made me realize i can have rock concert SPL without the harshness of titanium domes in breakup ...

of course Beyma AMTs are $700 a pop but "Airborne" AMT is $100 and although it has 10 db less output than Beyma it's still louder than any dome tweeter even if i were to use just one but i want to use twelve of them ...

you know to compare the sound of two good bookshelf speakers each with a 6" woofer and 1" dome assuming both of them are designed by a good company like Genelec or whatever - neither of them is actually "better" than the other - they will simply have different tune. to replace such speakers one with another is to run around in circles chasing your own tail - no time for that BS !

the only way to really UPgrade ( as opposed to SIDEgrade ) is to go up in SPL and displacement ... and i don't mean by 1 or 2 db but by 10 or 20 db ... and when i say upgrade displacement i mean by a factor of 10X to 20X as well ...

some fidelity loss is inevitable when you go up in SPL by orders of magnitude - my goal is to get to rock concert SPL while sacrificing as little fidelity as possible but i grew out of my audiophool phase - i'm at a point where i don't take people who talk about sound quality seriously - 99% of them are talking out of their ass. they can't hear sh1t they are just making it all up. i actually can hear things but i have come to realize that i don't care !

as i explained on another forum i only care about 3 things:

1 - speakers must go to ear-ringing levels without showing any strain
2 - bass must hit hard and deep without any distortion
3 - female vocals must sound real

for bonus points i would also like

4 - airy top end, meaning the same kind of awesome power above 10 khz as below 100 hz ...

 

[airborne]

+1 on CBTs or Murphy Corner semi infinite arrays. Line arrays are great for SPL and range but sacrifice directivity. You could also look into line sources, with high quality tweeter/midranges in the center to reduce cancellation. I know GR Research, despite their reputation, has a good video outlining the differences and benefits

i never have and never will build any speaker that i haven't 100% designed myself from start to finish and that isn't 100% original with no similar speaker existing anywhere on earth

for me the point of DIY is to make it original and uniquely mine with nobody else on the planet having a similar design unless they copied mine, which they are welcome to do

there are some people who will only have sex with men or women that are married to somebody else

and there are others who will only have sex with virgins

for me - i only care about building things if nobody has ever built anything similar before - i already redesigned this system about 100 times ( it started as a 5-way horn system, and is now an array ) and not one of those design iterations was like anything that has ever been done ...

my worst fear is that by the time i learn all the science that there is to learn my design may end up morphing into something that has already been done before - i might have to slit my wrists then

the morons at DiyAudio insisted i MUST pick one of the designs they are building ( like synergy horn for example ) and build that. they told me i am not allowed to get creative. i told them all to go f*** themselves and they banned me. thus i am here.

well they were actually right that the design i posted there was problematic ... it was the 5-way horn system ... further research caused me to abandon that design ...

the array design is already starting to show signs of stress after briefly examining the JBL paper i linked - i first tried following the math and couldn't - then i just looked at all their diagrams and understood it easily - now i want to go back and read the math again now having the benefit of knowing what the result of all those calculations was ...

anyway ... i am not about to build something to just to validate somebody else's design. my designs are to validate ME not somebody else.

my designs are supposed to prove that i am a creative genius with rock solid understanding of the science involved ... unfortunately as it turned out my understanding of science is actually GARBAGE and i literally have no clue - but that's exactly what i'm trying to fix !

 

[Wesayso]

So why the move away from horns?
They can do your complete list:
1 - speakers must go to ear-ringing levels without showing any strain
2 - bass must hit hard and deep without any distortion
3 - female vocals must sound real

Signed, Wesayso, a moron from DIYaudio...

Make your own version of this:

It could blow your head off...

 

[airborne]

So why the move away from horns?
They can do your complete list:
1 - speakers must go to ear-ringing levels without showing any strain
2 - bass must hit hard and deep without any distortion
3 - female vocals must sound real

Signed, Wesayso, a moron from DIYaudio...

Make your own version of this:

It could blow your head off...

compression drivers have 100 times higher distortion than AMT ribbons ... that's according to Beyma who makes both and publishes AES papers on optimizing compression driver distortion ...

once i realized this fact the Horn idea sort of didn't make too much sense anymore ...

but now i'm realizing that getting arrays to have a flat response is only possible with floor to ceiling array or in an open space without a ceiling

but i actually have sloped ceiling and worse than that - what if i move to a space with a normal ceiling ? it is impossible to design an array that will work with any ceiling unless you make it flexible enough to where it can be re-shaped like prosound arrays can be ...

the complexity of building an array that can be bent like a prosound array to match the ceiling situation would be insane ...

not giving up yet though, i have only started the research ...

 

[Wesayso]

compression drivers have 100 times higher distortion than AMT ribbons ... that's according to Beyma who makes both and publishes AES papers on optimizing compression driver distortion ...

Luckily for the rest of the horn lovers out there, the distortion of compression drivers is low enough not to be a limiting factor...

 

[airborne]

Luckily for the rest of the horn lovers out there, the distortion of compression drivers is low enough not to be a limiting factor...

yes if you use a 130 db compression driver only up to 90 db distortion will be quite low

if you drive it to full power distortion can easily hit 50% or so ...

you will have paid $500 and gotten $20 worth of performance

oh look my DAC has 0.0001% distortion and my amp has 0.001% distortion and my tweeter ... 50%

woops ...

on other hand with AMT ribbon even though its peak SPL may be lower than that of compression driver ... it will be able to go louder for a given distortion level ... so you're actually getting your money's worth

not only that but the $100 Airborne ribbon is flat to 30 khz without any breakup while most compression tweeters are only flat to about 5 khz and go into bad breakup above 10 khz or so ...

every technology has its fan base - whether it is horns, transmission lines, tubes, vinyl etc ...

but 100% of the most technically advanced and highest performance speaker systems are arrays ...

 

[Ericglo]

You haven't given a budget.

I agree with Wesayso. A horn might be a better approach. Look at B&C's new coax compression driver and the new horn to go with it. Pair it with a big woofer and it should give you the ear shattering SPLs you desire.

Test Bench: B&C Speakers DCX464 High Power Coaxial Compression Driver and Horn

The driver to be characterized in this Test Bench is from B&C Speakers and is the DCX464, a pretty unusual ring radiator compression driver. First, because it’s a coaxial compression driver - a rare category of compression driver, and second because the DCX464 compression driver and the...

audioxpress.com

If you want to do something that not many people have done, then try a CBT. You could go with some planar drivers and some woofers from Acoustic Elegance for high SPLs.

Test Bench: Radian Audio Engineering’s LT6 Horn-Loaded Ribbon Planar Device

In this article, Vance Dickason measures the Radian Audio Engineering's LT6 Horn-Loaded Ribbon Device, part of an expanding series designed by 35-year loudspeaker engineering veteran Igor Levitsky for the Californian manufacturer. The LT6 is a pro sound driver but was designed to be a more...

audioxpress.com

 

[airborne]

You haven't given a budget.

I agree with Wesayso. A horn might be a better approach. Look at B&C's new coax compression driver and the new horn to go with it. Pair it with a big woofer and it should give you the ear shattering SPLs you desire.

Test Bench: B&C Speakers DCX464 High Power Coaxial Compression Driver and Horn

The driver to be characterized in this Test Bench is from B&C Speakers and is the DCX464, a pretty unusual ring radiator compression driver. First, because it’s a coaxial compression driver - a rare category of compression driver, and second because the DCX464 compression driver and the...

audioxpress.com

If you want to do something that not many people have done, then try a CBT. You could go with some planar drivers and some woofers from Acoustic Elegance for high SPLs.

Test Bench: Radian Audio Engineering’s LT6 Horn-Loaded Ribbon Planar Device

In this article, Vance Dickason measures the Radian Audio Engineering's LT6 Horn-Loaded Ribbon Device, part of an expanding series designed by 35-year loudspeaker engineering veteran Igor Levitsky for the Californian manufacturer. The LT6 is a pro sound driver but was designed to be a more...

audioxpress.com

what's a CBT ?

radian is trash. planar magnetics are trash. acoustic elegance is trash.

Beyma and Eighteen Sound AMTs are the best tweeters on earth - can't afford them.

budgets are for Americans. Americans live to spend money - but i am Russian, well Ukrainian but it's the same thing.

bottom line i don't have a goal to spend X amount of money because i don't live to keep the federal reserve in business.

my goal is to build a speaker as best as i can for the least amount of money for which it can be built.

the Airborne AMT is the cheapest full-size AMT on the market - literally cheaper than Dayton Trash - that's why i want to use it.

if cost was no object i would have used Beyma or Eighteen Sound, followed by Aurum Cantus - all of them can cross at 1 khz while the Airborne can only be crossed at 3 khz, which is a severe limitation, but Airborne is $100, Aurum Cantus is $300 and Beyma / Eighteen Sound are $800 each ... so Airborne it is

 

[BlackTalon]

I suspect you have no idea what 'budget' means...

Best sound for how much money? $100? $300? $2,000? Don't you think driver selection, etc. will depend on whether or not you are limited to $15?

 

[airborne]

I suspect you have no idea what 'budget' means...

life is too short to try to unprogram every victim of brainwashing ...

much faster to add them to ignore list ...

bye bye !

 

[beefkabob]

there are some people who will only have sex with men or women that are married to somebody else
and there are others who will only have sex with virgins

Please tell me more.

my worst fear is that by the time i learn all the science that there is to learn my design may end up morphing into something that has already been done before - i might have to slit my wrists then

You mean that an engineering problem being already solved would lead to you committing suicide? Seems a bit extreme.

the morons at DiyAudio insisted i MUST pick one of the designs they are building ( like synergy horn for example ) and build that. they told me i am not allowed to get creative. i told them all to go f*** themselves and they banned me. thus i am here.

well they were actually right that the design i posted there was problematic ... it was the 5-way horn system ... further research caused me to abandon that design ...

How to win friends and influence morons... who were actually right all along.

anyway ... i am not about to build something to just to validate somebody else's design. my designs are to validate ME not somebody else.

my designs are supposed to prove that i am a creative genius with rock solid understanding of the science involved ... unfortunately as it turned out my understanding of science is actually GARBAGE and i literally have no clue - but that's exactly what i'm trying to fix !

Please, tell me more about your mother.

radian is trash. planar magnetics are trash. acoustic elegance is trash.

Don't forget the Kardashians.

budgets are for Americans. Americans live to spend money - but i am Russian, well Ukrainian but it's the same thing.

Yes, yes, and... ohhh... A few million armed Ukrainians may disagree with that. Just ask Vladimir. He gets it.

bottom line i don't have a goal to spend X amount of money because i don't live to keep the federal reserve in business.

You prefer the gold standard then?

my goal is to build a speaker as best as i can for the least amount of money for which it can be built.

Laudable.

if cost was no object i would have used Beyma or Eighteen Sound, followed by Aurum Cantus - all of them can cross at 1 khz while the Airborne can only be crossed at 3 khz, which is a severe limitation, but Airborne is $100, Aurum Cantus is $300 and Beyma / Eighteen Sound are $800 each ... so Airborne it is

Sounds like you have a budget.

life is too short to try to unprogram every victim of brainwashing ...

This is true, but perhaps inadvertently ironic.

much faster to add them to ignore list ...

bye bye !

That's not very nice. Looking forward to joining airborne's list.

 

[airborne]

planar magnetics are trash.

actually changed my mind yesterday.

certainly AMT is far superior to planar magnetic but AMTs only come as tweeters

planars also come as mids

and AMT tweeter with planar mid could actually be a perfect match

i was just struggling to find a suitable cone driver smaller than 4" in diameter to act as a midrange to go up to 3.5 khz without beaming ...

anything smaller than 4" is a "full range" and those sacrifice output capability for wide bandwidth. a true midrange is narrow-band but loud, which is what i want, but they only come in 4" to 10" size. if on other hand you try to cover 200 hz to 20 khz with one driver output capability will suffer, and line arrays are bottlencked by output capability in the higher frequencies ( still have to do more reading )

i looked at Bohlender Graebener Neo 8S midrange yesterday and these drivers have some useful properties for a line array midrange ...

 

[airborne]

Looking forward to joining airborne's list.

Vires in Numeris ...

 

[airborne]

i looked at Bohlender Graebener Neo 8S midrange yesterday and these drivers have some useful properties for a line array midrange ...

essentially there simply are no good line array midrange options except planars as much as i think Planars are trash ...

AMTs are much more dense and linear than Planars but have one issue ...

the flexible AMT diaphragm isn't supported by anything - it flops around in the wind basically ... making it impossible to pressurize a chamber behind it to produce lower frequencies ...

this is why most AMTs like Aurum Cantus are open back - they market them as being dipole capable but it's complete BS - the reason they don't include a rear chamber is it would ruin the measurements - they use open back design because AMT can't pressurize a chamber ...

in this sense AMTs are like true ribbons, which also can't pressurize a chamber because they aren't even airtight ...

the reason AMT can't pressurize is because motor force is sideways - there is no force in the direction needed to compress the air in the chamber ...

the benefit of AMT is motor force is constant with displacement resulting in low distortion ... and also extremely dense packing of radiating surface and conductors into a narrow line source resulting in good horizontal dispersion ...

basically true ribbons make good supertweeters

AMTs make good tweeters

planars make good upper midrange

because planars actually CAN pressurize a chamber, but they are much wider than AMT and thus more prone to beaming ... but also they are less linear and prone to resonances in the passband ... which is why i called them "trash"

in a perfect world we would have an AMT with some support of the diaphragm to stabilize it from flopping back and forth driven by changes in chamber pressure ... but low end would still be limited due to the need to flex the light but stiff pleats resulting in a high FS so to speak ...

in fact an AMT has two resonance frequencies - that of the pleats and that of the chamber - but both are pretty high

Planars can go a lot lower ... albeit with crap quality - right in the heart of the vocal range - ouch !

but what's the alternative ? i can do an array of 4" mids like this:

Single Product | Lavoce Italiana Pro Audio Speakers

www.lavocespeakers.com

but even though genelec runs 4" to 3 khz it's kinda stretching it IMO ...

or i could use smaller drivers like this:

2FE24 (8Ω) by FaitalPRO

FaitalPRO combined the latest R&D methods and technologies with the most advanced industrial automation techniques and all FaitalPRO drivers are made in Italy with the highest level of quality, consistency and durability.

faitalpro.com

but output is kinda low ...

 

[airborne]

Test Bench: Radian Audio Engineering’s LT6 Horn-Loaded Ribbon Planar Device

In this article, Vance Dickason measures the Radian Audio Engineering's LT6 Horn-Loaded Ribbon Device, part of an expanding series designed by 35-year loudspeaker engineering veteran Igor Levitsky for the Californian manufacturer. The LT6 is a pro sound driver but was designed to be a more...

audioxpress.com

you know what ... as much as i hate Planars and Radian your post was unintentionally brilliant because this driver >>>

LM8K - Wide Band Planar Ribbon Transducer

Neodymium magnets and Kapton diaphragm Smooth extended response Superior sonic transparency and resolution of vocal range Extremely wide and even horizontal dispersion Reliable design for long term operation Environmental protection Optimized for line array application...

radianaudio.com

is actually fairly solid value mid-tweeter !

i had no idea Radian was making line source drivers - i thought they just make those stupid beryllium compression drivers.

to use this Radian mid-tweeter with the airborne tweeter with 1 khz and 6 khz crossovers versus to just use the Aurum Cantus down to 1 khz is about the same price ...

this is like that situation where the donkey dies of starvation between two piles of hay unable to decide which one to eat ...

 

[airborne]

well i have some bad news and some worse news ...

basically realized Airborne / Hygeia is trash so now i am named after Trash ...

but the worse news is that i realized that what i actually need is starting to enter Beyma price territory ...

i realized i need Aurum Cantus G3 true ribbon supertweeter crossed to Radian LM8K mid-tweeter ...

basically it's what i said before

True Ribbon > Supertweeter
AMT > Tweeter
Planar > Mid-Tweeter

you either have to run AMT all the way down to cone drivers or you have to run True Ribbon with Planar

the problem with AMT all the way down to cones is AMTs are fairly wide so they beam above 10 khz ...

nor do they really go very low for reasons explained earlier ...

i just kinda got carried away with the whole AMT idea when i read the Beyma paper about how they have 100 times lower distortion than compression drivers while also being robust and loud and true line sources ...

but having had some time to think about it as good as AMT technology is it does have those two issues mentioned above ... i just got too focused on the very real benefits of AMT and neglected to consider the downsides ...

this is sort of how i keep cycling through these design iterations ... it's horrible !

 

[airborne]

the advantage of True Ribbon is it is narrow ...

now to most people this would be a disadvantage since they're using a single unit and trying to get it to cross to something like a 6" woofer and they don't have enough ribbon area to get low enough in frequency ...

but if you're using a line array and crossing to planar mid-tweeter capable of going to 10 khz then you don't need the area or the width ...

Aurum Cantus G3 ribbon is just 8.5 mm wide, which is 40% of the wavelength of sound at 16 khz - that's PERFECT for horizontal dispersion all the way up ...