• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Everything you ever wanted to know about Line Arrays ( but we’re afraid to ask)

dasdoing

Major Contributor
Joined
May 20, 2020
Messages
4,208
Likes
2,673
Location
Salvador-Bahia-Brasil
The idea is that, if you have a perfectly reflective floor and ceiling (which never happens), then the floor and ceiling will act as mirrors, and "images" of the speakers will be appear above and below the room, making the line array extend infinitely above the ceiling and below the floor. So, in your simulation, picture an infinitely tall array with infinite number of drivers, and the sound will only radiate horizontally and uniformly.

what?
if this was possible I could use a single driver on the floor and put a board on top, no?
 

NTK

Major Contributor
Forum Donor
Joined
Aug 11, 2019
Messages
2,656
Likes
5,819
Location
US East
no but the board fills the space up to the ceiling. than the ceiling fills to infinitty
Remember the "listener" also has to be between the floor and the ceiling. And the rules regarding the separation distances between the sources (< λ), including the distances between the "real" source and its mirror images, still apply.
 

dasdoing

Major Contributor
Joined
May 20, 2020
Messages
4,208
Likes
2,673
Location
Salvador-Bahia-Brasil
Remember the "listener" also has to be between the floor and the ceiling. And the rules regarding the separation distances between the sources (< λ), including the distances between the "real" source and its mirror images, still apply.

ok, I sandwich two 1" drivers between two boards and have them at ear height.
 

somebodyelse

Major Contributor
Joined
Dec 5, 2018
Messages
3,680
Likes
2,958
ok, I sandwich two 1" drivers between two boards and have them at ear height.
Unless you can fit your head in that 2" gap ( I couldn't!) it's got to have an opening into your room, at which point the behaviour changes.
 
  • Like
Reactions: NTK

LesterNZ

Member
Forum Donor
Joined
Sep 22, 2020
Messages
25
Likes
38
A very good overview of a Line Source for near field (domestic) use is here:


A slightly old, 2003 paper, though he's very good on the subjects of V and H directivity index and for power tapering with floor-ceiling bounce reduction which helps the "scaling" (huge single instrument/vocalist etc.) imaging thing. And right off, I'll say big orchestral, big band, stadium pop - whatever, simply sounds more lifelike from all those un-stressed lightweight little drivers. But they don't (can't) do that pin-pointy nonsense that only occasionally happens in the real world - if you get "just the right seat".

I built 2 line source systems based on this and McIntosh's Roger Russell's papers. (AudioXpress-Speaker Builder re-printed).


My first effort was with 28 Tang-Band 3 inch paper cones. And the second system was with 74 Peerless 'FR' 2 inchers. I had a great time in these very labour intensive projects. E.G. Just tapping screw holes 'exactly' for hundreds of little M3 or M4 screws taught me "careful-careful-steady". Plus all wiring & measuring series-parallel sub-groups while maintaining polarity required a painful reduction in workshop beer consumption.

Shame about those paper three inchers that just didn't actually get above 9 or 10kHz. No EQ pushing helped. I measured DC impedance & 50Hz "buzzability", but should've FR swept them all - FIRST! Live & Learn, the hard way! Although I probably can put a 5 kHz Raven ribbon at, or a little above ear height, and 'maybe' fix this design flaw. The 74 Peerless 2 inchers are great little singers - and they're smooth & peak over at 22kHz which is far beyond my aged perception. Matching with woofs below 150 - 300Hz was easy, and I even had some decent sonics with my 4x sealed Peerless XLS 10's at 460 Hz, L-R 4th order.

So, any Line Source build is labour intensive - big factory or your DIY bench. There's all those little parts that want to rattle, and all those wires to be correctly placed & soldered etc. Probably why we don't see more of them in shops. BOM and assembly time. Shipping 6 foot+ or 2M+ plus 'delicate' heavy structures isn't cheap. Is it?

But they can make music beautifully, and because of their 'slimness' can disappear in domestic situations - behind drapes, on window frames, or wherever you can position a "sort of" pole lamp. They can provide big "good" music capabilities on a very small footprint.

Friends with ESL panels & Maggies like my efforts and that's OK enough for me.

Have Fun
JP
 

benanders

Senior Member
Joined
Nov 12, 2022
Messages
391
Likes
411
Location
Hong Kong SAR
Wasn’t addressed directly yet - DSP a must if any line array is to show normal measurements. If you’re in the well-measuring speakers camp, life will be a harder slog with lines, albeit more fun, too, if you like software (re-enter @Wesayso efforts).

I’ve listened to a number of line array models and although my own setup admittedly contradicts certain principles of true line arrays - perhaps I should call mine lyin’ arrays - their attributes have been well-described by the previous posts, along with the drawbacks (also: no close sidewalls unless you build a Murphy Corner).

I always refer to the effect of mine as: not the sound everyone will want at home, but I’m still looking for the person who doesn’t love it.

One thing should be pointed out. Line array designs in-home are not the same as PA kit, and the effects tend to be quite different. Some of the hifi line array models I’ve heard in home / showroom setups do a remarkable job of blending attributes of live venue x hifi. Some purists would call that “speakers coloring the sound.” Maybe.

If you like the studio concocted pinpoint imaging inherent to recorded music, however, then your typical move with line arrays will be to
1683523195264.gif
 

Philbo King

Addicted to Fun and Learning
Joined
May 30, 2022
Messages
669
Likes
871
Interestingly, Bose came out with mini-line array PA speakers about a decade ago. In a small enclosed venue they sound great (for a PA) and prevent the need for stage monitors or IEMs. This is the first exception to the old pro audio adage "got no highs? Got no lows? Must be Bose!"

On the other hand, since their radiation pattern is basically a horizontal toroid, they really need reflective walls or corners behind them. This makes them pretty useless for outside gigs where no walls are nearby.

 

LesterNZ

Member
Forum Donor
Joined
Sep 22, 2020
Messages
25
Likes
38
There was the quite popular Shure Bros "Vocal Master" (often: "Blaster") systems long before the Bose Arrays. And the the grey box columns of all those mid-range drivers could often be seen in many churches & small auditoriums. Musicians would put them up on chairs or tables in club-hotel lounges etc where in all these locations they effectively did what they were named to do.

At home, in the 1950's-70's, the fully-loaded Bozak Concert Symphony, or something grandiose like that, had a multiple vertical tweeter array that covered any room pretty nicely. And sounded pretty good because each driver didn't have to do too much work to get up to respectable SPL's for whatever was fed to them.

Again, it's the price with high Basic Order of Materials (BOM) and construction & shipping complexities that keep these "better" (low distortion, wider dispersion etc) designs out of mainstream markets.
IMHO, at least DIY'ers could eventually make their wettest dream build come true with a Line Array project.
jp
 

MoreWatts

Addicted to Fun and Learning
Forum Donor
Joined
Oct 30, 2022
Messages
714
Likes
811
Location
The Mojave Desert
A short video on the use of line arrays at the Coachella Music Festival, and how they revolutionized festival sound, in general. Uneven sound and speaker arrays too large and too heavy pushed the need for a better way. I cracked-up when he said how they used to 'eyeball' speaker placement in the old days, and how that has changed. :cool:

 
Last edited:

Bergante

Member
Joined
Sep 9, 2022
Messages
54
Likes
61
Location
Bilbao, Spain
I really liked small floor-standing line array PA system in a hall with 7-10 meter tall reflective glass ceiling

It was a huge improvement in regards to excessive reverberation compared to traditional PA speakers on stands in the same space

Slower than usual distance falloff was also a nice bonus

Same system as described here, same pros and cons as reviewer mentions, not great for nearfield but nicer than expected in farfield
I recently resigned, but I´ve been the sound guy at a jazz club in Bilbao for 20 years. The MAUI 28 has an unbelievable price performance ratio and it really shines when used for jazz concerts by blending with the actual live stage sound.

I have used them at a 400 seats auditorium and I still didn´t crank up the power to the maximum. But I don´t see the value at home. These things are optimized for listeners several metres away from the units.

Moreover, being a small line array they provide better sound pressure uniformity over different distances and even help prevent feedback (when you are close to them phase cancellations occur). And they especially help with the decay of high frequencies with distance. They help so much that, in order to achieve a "club" sound for brass I ended up attenuating high mids and beyond for sax and trumpet. I didn´t want a "bell close to your ear" sound, but a more natural "several metres away" and much more natural sound.
 
Last edited:

benanders

Senior Member
Joined
Nov 12, 2022
Messages
391
Likes
411
Location
Hong Kong SAR
...

I have used them at a 400 seats auditorium and I still didn´t crank up the power to the maximum. But I don´t see the value at home. These things are optimized for listeners several metres away from the units.


I think the utility of line arrays in homes depends on the size and use(s) of the room, and in some instances how “precise” vs. “overall” the listener(s) want sound to be. In big rooms where more than a few people mingle instead of sit stationary, home vs. small auditorium makes less difference in whether line arrays can serve well, IMO. PA line arrays, regardless of brand/model, will not often be advisable in a home hifi setup.

I agree that for many/most homes and in many/most traditional stereo listener cases, the ROI for many/most line arrays is probably a challenge. ;)
 

MaxwellsEq

Major Contributor
Joined
Aug 18, 2020
Messages
1,627
Likes
2,422
People may rationalize: "I'm trying to recreate the concert sound, but at home, so I should use line arrays at home". But line arrays of the type used in a stadium are for a specific use case that is never encountered at home. What is more, I think they create issues domestically which would count against their suitability.
 
Top Bottom