Advice on first ultra budget LINEARRAY

[blamus]

Hi, I am new to this forum and also new to DIY, in terms of practical experience, but I've been reading and researching in the past many many months and I think I am ready to build my first project:

Projects I have read include conventional TM/MTM/TMM 2ways, and all types of 3ways, full rage projects (e.g. using the markaudio CH70 drivers), subs, and line arrays.

I believe I have sufficient electronics knowledge to build XOs etc, but not the experience to design them, so I have only planned to build existing projects.

I have no experience in building boxes and this is what scares me, but I do have a friend whose uncle is a skilled carpenter and will be able to help me/provide tools.

So, with my above mentioned experience, I decided the easiest type of speaker to build would be something along the lines of a single fullrage driver sealed/BR (so no XO or just a simple filter) or a fullrage line array (again no XO, or complicated boxes with different mounting options etc.)

basically I am keep coming back to 'fullrage' for the easiest and simplest implementation. Am I correct?

So, anyway, I have finally decided to build a line array such as this:

http://www.parts-express.com/project.../Kuze3201.html

Looks like I can just slap a load of drivers connected together into the right impedance in a line, maybe add a filter, a bit of external eq, pair with a sub, and I'll get great sound? Or is it much much much more complicated than that?

Anyway, lets say I go ahead with this project, I'd like to go super budget and use these drivers:

http://www.parts-express.com/pe/show...number=289-124

1.
I cannot find any info on these things or anyone else using them. Are they suitable? IS this a bad idea? Any better suggestions for a better driver that is not significantly more expensive?

2.
I'm gona get 100 of them so they will be $2 each, how many should I have on each side for the average size sitting room, used for music as well as HT, paired with a 12" ported sub?

3.
Do I need to model them on computer and design an enclosure for them? Or can I just mount them in a pipe like the showcase or some kind of long thin box? If they need a specifically designed airspace/box can someone please help me and give me some suggestion? should it be ported? sealed? how big? etc.

4.
Do I need any electronics such as XO or filters for something like this? If so, any suggestions? A 100Hz highpass? so just a simple cap will do? I was hoping they would be ok full range.

5.
What is the best way to build the baffle for mounting all these little speakers? Do i need to drill 100 holes on a plank of wood to mount them? Or can I have 2 long planks of wood side by side, 2 inches apart, and just mount the drivers between them - but then there would be slight gaps between the drivers that need to be sealed?

any other advice would be greatly appreciated.

best regards.

[Dirk]

Re: Advice on first ultra budget LINEARRAY

Anyone who says line arrays are the simplest thing to build needs to put the bottle down.

Please tell me you've read Jim Griffin's line array white paper?

[blamus]

Re: Advice on first ultra budget LINEARRAY

I have actually been reading that, its on my desktop and I'm reading that bit by bit everyday. Please correct me if I am wrong, but from all the buildlogs I have been reading, they seem to be simple in the sense that they are fullrange - no XO design, cabinet design as simple as the average sub (just model the correct volume) - i.e. no need to worry about flush/surface mounting, BSC, etc etc. in the conventional 2/2.5/3 way speaker, no need to match the right tweeter to the right woofer and a specific XO with a specific box with specific mounting techniques.

I am only trying to build a fullrage (1-way) XO-less linearray, does that not take out most of the complications? I can imagine a 2-way etc line array would be way beyond me.

Do you have a better suggestion for me? I am really open to all types of advice.

I always wanted to build line arrays because I have never even heard one! I want to know how they would compare to the equiv. priced conventional speaker. For example, Ican build the tritrix for $200, but then thats just putting bits together as opposed to real down and dirty DIY, but thats not a problem as long as the performance is there. Would my mentioned line array be worse than something like the tritrix? Would I get more for my money if I just build something like the tritrix and call it a day? Or something like what was mentioned in the peerless buyout thread? mini Elsinore?

[nordhaven]

Re: Advice on first ultra budget LINEARRAY

BIB's are easy full range projects that actually have some bass.
http://www.zillaspeak.com/bib-howtobuild.asp

[Steve Henry]

Re: Advice on first ultra budget LINEARRAY

I have actually been reading that, its on my desktop and I'm reading that bit by bit everyday. Please correct me if I am wrong, but from all the buildlogs I have been reading, they seem to be simple in the sense that they are fullrange - no XO design, cabinet design as simple as the average sub (just model the correct volume) - i.e. no need to worry about flush/surface mounting, BSC, etc etc. in the conventional 2/2.5/3 way speaker, no need to match the right tweeter to the right woofer and a specific XO with a specific box with specific mounting techniques.

I am only trying to build a fullrage (1-way) XO-less linearray, does that not take out most of the complications? I can imagine a 2-way etc line array would be way beyond me.

Do you have a better suggestion for me? I am really open to all types of
advice.

I always wanted to build line arrays because I have never even heard one! I want to know how they would compare to the equiv. priced conventional speaker. For example, Ican build the tritrix for $200, but then thats just putting bits together as opposed to real down and dirty DIY, but thats not a problem as long as the performance is there. Would my mentioned line array be worse than something like the tritrix? Would I get more for my money if I just build something like the tritrix and call it a day? Or something like what was mentioned in the peerless buyout thread? mini Elsinore?

You might consider the ART Array design from Audioroundtable.com. It is a little more money, but has a simple crossover. Pete S. on this forum even modeled an improved crossover version.

[blamus]

Re: Advice on first ultra budget LINEARRAY

Thanks for the links and advice guys The art array looks nice but already it is a 2way, with big woofers and XOs.

I guess I should just refine my question:

If I build an array exactly like this:

http://www.parts-express.com/project.../Kuze3201.html

but replace all the drivers to this

http://www.parts-express.com/pe/show...number=289-124

Is it a bad idea? Any reasons it might sound like crap? Is it doable. etc. Whats your opinion?

[Steve Henry]

Re: Advice on first ultra budget LINEARRAY

The first problem I see with the buy-out drivers is extension to only 14K. The drivers in the showcase went to 20K. You may be lacking some on the top end. As far as an enclosure design, maybe you could send a couple of the drivers to someone on the board who could measure them. Then a proper enclosure could be designed.

[blamus]

Re: Advice on first ultra budget LINEARRAY

Thats a good point, thank you! I don't think I am too worried about the top end, I was hoping that I can EQ the top a little to help out. Also, are the specs on the site not sufficient to build a good enclosure?

But that is a very valid point and is starting to make me consider maybe just bulding the tritrix instead. But I so wish I can listen to some DIY arrays in person.

[Andy_G]

Re: Advice on first ultra budget LINEARRAY

Wide range drivers are generally not advised for line arrays.

The issue is that above a certain frequency, dependant on driver spacing, there will be what they call comb filtering. This generally manifests itself to the ears as a greater than expected roll off in the upper frequencies than the drivers actually have, so even if the wide range driver seems to extend quite a long way up, the upper frequencies will not actually be there as much as you hope.

Probably the cheapest way of doing a line array that will present a reasonably extended response is something like the Art array mentioned above. Use a good quality tweeter in the middle of either 8 equally powered mids or 10 mids in a 3223 power taper. (as in my 'Gumby')
http://members.optusnet.com.au/~grad...by%20final.JPG

Another is to use a column of cheaper small faceplate tweeters, closely packed alongside the central section of a line of mids.

[djg]

Re: Advice on first ultra budget LINEARRAY

Thats a good point, thank you! I don't think I am too worried about the top end, I was hoping that I can EQ the top a little to help out.

You can't EQ a speaker into producing frequencies it is unable to reach.

You seem to like the super slim tower look of the showcase project, it certainly is unique.

Bill Fitzmaurice has a line array design on his site. It does use tweeters. The people building these are very much into using the very cheapest buyout units available. You might find something interesting there.

www.billfitzmaurice.com

[diru]

Re: Advice on first ultra budget LINEARRAY

I have been looking at these, if I had the pocket to fiddle, these would be it.

So it might be lacking above 18k and about a 150 bottom, but room gain and a over sized box might make it to 100 or lower.

Lay'em 64 high horizontally, on one the next.

http://www.parts-express.com/pe/show...number=269-484

[marlboro]

Re: Advice on first ultra budget LINEARRAY

Don't do a crossoverless line array. You won't like the result.

Follow Jim's white paper.

The tweeter you suggest won't be able to cut the flange tight enough to avoid distortion.

Building line arrays that work takes a huge amount of pre-design planning. Its not as forgiving as a regular speaker system. Believe me I know. It took more 6 months of reading, 6 months of design, and then nearly a year to build them.

See Calipso's below.

Marlboro

[blamus]

Re: Advice on first ultra budget LINEARRAY

the link to the photo album doesn't work for me.

[Taterworks]

Re: Advice on first ultra budget LINEARRAY

First tip for most people considering a line array.

Stop. Right now.

Calculate the value of the drivers you will be purchasing for this project. I know the drivers themselves are only $1.67 a pop, but when you get 32 of them together, you've spent $50 on drivers.

For the same money in drivers, grab a pair of these: http://www.parts-express.com/pe/show...number=279-410

And four of these: http://www.parts-express.com/pe/show...number=292-310

Build a sealed MTM (1 cubic foot will suffice), crossed over 1st-order between 3000 and 3200 Hz. (First order filters mean your crossover will be cheap. It may be a good idea to go second-order on the tweeter, just to add robustness to the design and prevent damage.)

They'll play scary loud (91dB system sensitivity, no tweeter padding needed, plus the ability to take 180 watts 24/7), and even though the crossover design is based on dead reckoning, it'll sound way better than whatever cheap widebander-du-jour is currently being flogged as "Great for line arrays!" The sensitivities of the LF and HF sections are even a good match for each other.

The other reason to avoid line arrays if your application does not require their specific radiation pattern is thus: Your ears are not a line. The closer you sit to a line array (and in a typical room, you won't be sitting further than 12 feet from them), the greater the distance between the outermost driver and your ears compared to the distance between the middle driver and your ears. You'll be dealing with 16 individual sources radiating high frequency energy with very little pattern control. Some of this energy will be radiated throughout the room, and some will find its way to your ear, but the net result of all of this is that you'll hear smeared detail in the treble range (admittedly, something you're giving up already by using inexpensive wideband drivers).

My hypothetical $50/drivers design above would have the distinct edge over any line array in coherence at close range, and give you deeper bass and more extended highs than you'd get from the line of widebanders, and would be a lot less work to build. And unless you want to listen in excess of 115dB (at great cost to your hearing), it'd be plenty loud enough even with modestly-powered receivers.

So if you're still considering a line array with TV speakers, I urge you to reconsider for the reasons I've just presented. A line array built with cheap widebanders may mask some of the shortcomings of the inexpensive drivers, but it's not bringing you closer to the goals of high-fidelity.

(The big assumption in all of this is that you're considering a conventional vertical line array, and not a curved or frequency-shaded array. Frequency shading can be used to alleviate some of the problems line arrays suffer from.)

[blamus]

Re: Advice on first ultra budget LINEARRAY

Thank you for that advice, I understand what you are telling me and you have convinced me, along with other very helpful people over at DIYaudio.com I will no longer be considering building these cheap driver line arrays. I initially considered them because a thin line of them just look so cool, seemed cheap enough, and I always wanted to get into all this array talk. However I know understand alot more than before and see the inherent problem.

However, I am now considering the ART array, if, I can still get the parts for the $278 that PE offered sometime ago. If that deal is now off, then I guess I simply have to give up on arrays until i have that 1k to spend on a 2-way array with better midwoofers and planers.

Anyone know if PE still does the ART group buy deal?

Thank you.