3 Way Line Array, Lots of questions...

[A RandomGuy]

Hi guys I'm new here but I have browsed around here for quite a long time.

Just so you guys know.... I have never built a speaker in my entire life. And the only "reference" speaker I have atm is a Energy RC70. The reason I picked this place is because it seems there isn't any snake oil BS and everything is based on facts and good design. I know some basics but lack the immense amount of knowledge on here.

I have picked a few drivers and I am planning on using it for my 150" theater screen. It will be a absolute maximum of 93" tall.
I'm planning on using a active crossover with an SP2060. I am avoiding the DEQX due to price and sticking with the SP2060 since it is supposed to sound better then the DCX2496 according to other forum members in another forum.

I'm thinking of using Emotiva XPA-1 due to their measured performance and low distortion.

I'm also upgrading my PT-7030 to an Emotiva XMC-1 Next year for it's fully balanced circultry and dirac next year. Yes it's XLR is fully balanced.

My goal is to create a extremely accurate Line Array for seating 13+ feet away. If I can succeed creating a accurate(without a raal) dynamic line array with practically no SQ loss I would be extremely happy.

My room currently is shown in the below video link:
Sherbourn PT 7030 - Around the Theater with the new Pre/Pro - YouTube

=======================================================
Midrange:

Bohlender Graebener Neo8 Planar Transducer

11 Per side - 86-5/8" Tall

The reason I'm picking this driver is simply because it has some of the most detailed midranges. I'm planning on using it between 650 - 2.8-2.9khz and shouldn't run into any problematic horizontal dispersion I think
=======================================================
Tweeter:

Fountek NeoX 3.0 Ribbon Tweeter with Silver Faceplate

15 Per side - 85.05" Tall

I cannot afford Raal at nearly 5-6 times the cost.... and simply because it has similar performance to the raal at the upper registers according to people I randomly read on various forums. Raal being a great performer and able to crossover low seem to be making the difference. But please correct me if I'm wrong. Since ribbon are supposed to be the most detailed and due to space and looks. I thought this was probably the best choice

Other tweeters I have considered....
Hiquphon OW2 tweeter - I did not consider this one because of spacing between the drivers
Raal 150-15D - I cannot afford

=======================================================

Woofers:

Seas E0021-08S W12CY001
I just recently did some research on this one yesterday... and supposedly have very good bass precision and low distortion. And the driver looks cool around 200$ mark

Scanspeak - 18WU/4747T00
I know people like these ones a lot but the price is a bit high.
It seem that it is a fact that these have a nice "warm" sound that many people like. I may consider these once I have listened to them.

Seas Excel W18EX001 (E0017-08S) 7" Magnseium Cone Woofer
Larger driver/ Better base Extension compared to the other SEAS driver.
Not sure about distortion. but I'm assuming it is another accurate SEAS driver.
Looking at the FR it looks like it's something that can be used.

=======================================================

Cabling: ETP Copper from BJC
Err... it's good quality cable


I think in "theory" it should work.
Things I do not know is...

Cabinet thickness? Need a lot of reinforcing?

Speakers spacing, is having them right beside each other stop lobbing as I have heard with line arrays?

Would it be a problem with this array?

Would using the Small SEAS Driver work?

Would the Larger SEAS driver be better?

Is the BG neo the best choice for this?

Are the crossover points around were they should be?

Would a 4th order crossover be best?

Would I have to get DC protection for the Fountek Ribbons in an active crossover?

I'm planning to using a steeper slope crossover, Is it a good choice?

What books would you suggest that would get me up to date on design?

What software do you use?

What equipment should I use to test?

Is TrueRTA good?

What MICs are recommended?

Is there really a difference between MICs?

Setups and tips?

I'm planning to have this setup sealed, is that a good idea?

I think parallel series is only choice right?

Would time alignment be a big problem with this array?

If so, what would I need to do and would it be worth it?

Tweeters on the inside or outside or is it mostly aesthetics?

Maybe Rick Craig can have some input on this if he's around =P?

I realize my room is flawed and there is nothing I can do about that stupid fireplace... Would this setup work?

Would there be horizontal problems?

Is there other amps you may recommend are very low distortion and accurate?

Would yamaha pro amps be recommended?

I'm always open to any suggestions as I am a noob here...
I look forward to your responses.

-Steve

 

[planet10]

Neo8 Planar -- 11 Per side - 86-5/8" Tall
NeoX 3.0 Ribbon Tweeter -- 15 Per side - 85.05" Tall
Seas E0021-08S W12CY001
Scanspeak - 18WU/4747T00

An aweful lot of money to spend on a 1st speaker project. The woofer array should be floor to ceiling as well. You should choose quanties of drivers that series/parallel into a reasonable end result (ie 11/side is a no-go).

Cabinet thickness? Need a lot of reinforcing?

Depends on how elegant the box design is. Not much needed for the mid-top. The bass arrary is likely going to be best as a well-braced box, 18mm quality ply will likely be sufficient.

Speakers spacing, is having them right beside each other stop lobbing as I have heard with line arrays?

As close as possible

What MICs are recommended?

It should at least be calibrated.

Is there really a difference between MICs?

Huge. The usual cheap candidates are not much good above 10k.

Would time alignment be a big problem with this array?

Yes. Since it is a line array next to impossible.

dave

 

[A RandomGuy]

Huge. The usual cheap candidates are not much good above 10k.

Are there ones that had a good track record for performing well?

Yes. Since it is a line array next to impossible.

Would multiple drivers (like Bass drivers) flatten out frequency response? Or it wouldn't work the same way? I did notice that some measurements on other arrays showed peaks and valleys of +/- 3-6 dB

An aweful lot of money to spend on a 1st speaker project. The woofer array should be floor to ceiling as well. You should choose quanties of drivers that series/parallel into a reasonable end result (ie 11/side is a no-go).

I am planning to make it a woofer array as well. But I haven't decided on the driver since there is not much information comparing the drivers.
I picked those drivers because of it's known performance. But would probably buy one to try out.

But hey! It's still cheaper then the B&W or Wilsons... and I'm hoping it would perform a lot better. But in theory these drivers should blow them away.

 

[A RandomGuy]

Maximum Speaker Height of 93"

Driver total heights assuming they are going to be right beside each other touching.

BG Neo 8
10 = 78-3/4"

Fountek NeoX 3.0
14 = 79.38"

Seas Excel W18EX001 (E0017-08S) 7" Magnseium Cone Woofer
12 = 83.14956

Does that look right to you? Should make it better for wiring with parallel series.
Umm... Does having one of the drivers slightly longer effect sound in a negative way?

Is the smaller SEAS Driver better in this application?
What should I used to calculate box size for speakers used?

 

[planet10]

10 BG Neo 8

4 ohms nominal, could be wired for 10 ohms (OK)

~$2k

14 Fountek NeoX 3.0

8 ohms nominal, could be wired for just over 2 ohms (not OK) or 28 ohm (also not OK)

~$4.5k

You'd be better off with 12.

12 Seas Excel W18EX001

8 ohms nominal, could be wired for 11 ohms (OK) or 6 ohm (OK)

~$5.8k

Does having one of the drivers slightly longer effect sound in a negative way?

decreases the maximum XO point

There are a lot of other ways i'd spend $12k on my hifi/HT

dave

 

[A RandomGuy]

There are a lot of other ways i'd spend $12k on my hifi/HT

What would you do?

I picked these drivers because of their good reputation here and being able to produce very accurately.

Do you know something that will perform better and cheaper ?

I know the Emotiva XPA-1 can handle 2 ohms according to the engineer(Loonie) to a very high wattage. Since I'm most likely not going to be coming anywhere close to maxing it out I think running 120v should be fine.

I do not have space for more speakers for a full 7 ch. And I listen to music a lot.
I'm trying to get as much performance as I can get from a 2.1 ch setup. All I need is a bit of treatments and some moving of furniture.

btw, your not so far from me I'm just an hour from Vancouver.

Would still like to know a bit about Fountek ribbons and still some unanswered questions >.<"

 

[Jim Griffin]

Your project is certainly ambitious. If you haven't studied my Near Field Line Array White Paper, then you should. It is located at:

http://audioroundtable.com/misc/nflawp.pdf

Fred Thompson has recently constructed a three way open back line array with a DEQX DSP controller. This is at:

The DR912ad Open Baffle Line Array Speakers

An excellent resource is to contact Rick Craig at:

Selah Audio

Rick has been using Don Keele's CBT technology in most of his recent efforts.

Don't buy anything until your plan is solidified and you have thought through everything. Best of luck.

Jim

 

[Generic George]

It's basically a bad idea to get ambitious as your first project. If you really want a high end line array, just contact Rick Craig directly and ask him to design one for you. He charges quite reasonable fees for doing so and has LOT more experience with line arrays than you will ever likely have.

If you want to experiment and learn, I'd highly recommend a digital crossover, possibly something like a pro amp wt DSP built in like a Behringer iNuke.

Also one of the beauties of a line array is that you can get excellent results from very cheap drivers, since none of them will have to work very hard. So PartsExpress always seems to have various drivers for a couple of bucks and you can pick up 20-30 of them for a nominal sum.

There's a lot of little things that go into speaker building that the only way to really learn is to go out there and do it.

Finally, invest in some good measuring tools like a calibrated usb microphone, without something like that you are flying blind.

 

[planet10]

What would you do?

1st off i wouldn't be doing a line arrary. And i'd be spending more money on quality electonics.

If you are set on a LA & ribbons, you should contact Bob at Creative Sound in Abbotsford.

You should note that with a typical SS amp every time you halve the impedance, you double the distortion.

dave

 

[planet10]

It's basically a bad idea to get ambitious as your first project.

+ 1

dave

 

[A RandomGuy]

Thanks a lot for the Jim for the White Papers.

I will definitely be active, that was the plan from the start!
And I am definitely not buying anything yet That's why I checked with you guys.

Finally, invest in some good measuring tools like a calibrated usb microphone, without something like that you are flying blind.

I am still looking for a one that you guys might recommend.
I have also heard there is a "thump" noise for behringer units.

I don't think I'll be maxing out the amps on the XPA-1s I'm waiting for the Gen 2 to come out with 60 watts of class A. I think I won't come anywhere close to audible distortion

Atm the specs are at
1,000 watts RMS @ 4 ohm (0.1% THD)
500 watts RMS @ 8 ohm (0.1% THD)

And bench tests
Emotiva XPA-1 Monoblock Power Amplifier - Secrets of Home Theater and High Fidelity

So should I buy these drivers to try in a small 2 or 3 way bookshelf or floor standing speaker first?
I know that line arrays are very different though, but at least I know what they sound like in different configurations.

I currently have a pt-7030 which is very good compared to my previous Yamaha. I currently have my Parasound A21 as the AMP. It sound is clear and almost 3D?

I'm not really sure as to what electronics you think I should get. My mind is definitely set on getting MICs for calibration and then Dirac in February next year with the new pre/pro.
I will still need a recommendation so I can look up these things...

It's basically a bad idea to get ambitious as your first project. If you really want a high end line array, just contact Rick Craig directly and ask him to design one for you. He charges quite reasonable fees for doing so and has LOT more experience with line arrays than you will ever likely have.

I have noticed Rick has quite a few line arrays, obviously I cannot even compare to him since he does it as a living and acquiring knowledge/experience from using so many drivers. I have seen his Tempestas as well with the accuton drivers. He would probably have more experience then most people on here... I still want his raal+scanspeak Line array. But I also want to learn as well and understand why something is implemented. That's why I'm here right? How much does he generally charge? Does he explain why something is done a certain way?

I'm the kinda guy that wants every detail. Sorry if I'm asking too many questions.
If there is more info like white papers etc that would be great. I'm still interested in any information and experiences including books that are recommended.

Some time ago I was told by Rick that a Line Array is better for my setup. I didn't ask him much since he's running a business.

Anyways, I'm still here to look for information. Obviously we can't buy every single driver in the world right?

I really don't care if anyone overwhelms me with information

At some point in my lifetime I hope I am gonna build some sort of an array

 

[architect7]

Completely off topic, but how is the video switching speed with the 7030? I have the 7020 and it is painfully slow compared to how fast my TV can switch inputs. I am considering an upgrade to the 7030. Isn't it fully balanced like the XMC-1 will be? Edit: just found this: http://emotivalounge.proboards.com/thread/30712/sherbourn-7030-preamp-official-thread?page=7

Thanks!

 

[planet10]

Another line array paper (Taylor 1964)

http://p10hifi.net/TLS/downloads/taylor-line-array.pdf

dave

 

[A RandomGuy]

Completely off topic, but how is the video switching speed with the 7030? I have the 7020 and it is painfully slow compared to how fast my TV can switch inputs. I am considering an upgrade to the 7030. Isn't it fully balanced like the XMC-1 will be?

Thanks!

I can try when I hook up another source maybe today or tomorrow. I think it's maybe a second. Atm, I only use my computer as my source. The PT 7030 is not fully balanced according to Andrew Robinson and the one of the Sherbourn guys I believe.

And thanks for Papers Dave!

 

[architect7]

I can try when I hook up another source maybe today or tomorrow. I think it's maybe a second. Atm, I only use my computer as my source. The PT 7030 is not fully balanced according to Andrew Robinson and the one of the Sherbourn guys I believe.

And thanks for Papers Dave!

Thanks! After some quick research, that will be amazing to have fully balanced analog with the XMC-1. Looks like I will cancel my Marantz upgrade and wait for the Emotiva instead

And best of luck with your project. I run a "simple" system with RAAL tweeter, SEAS W15CY mid and SEAS W22EX woofer, 1 of each per channel, all open baffle and the results are astounding. And SPL is a non issue, I haven't officially measured it but it will crank distortion free far beyond my comfort zone. Which is impressive because I like to listen LOUD on occasion. Imaging is incredible as well. My only gripe is mid-bass "kick" which I will be fixing with a pair of W22EX woofers per side, sealed.

I also agree with many others here regarding the ambition of your first project. I am on my 3rd (or 4th?) iteration of my project in 2 years and I am glad I never invested a great deal in baffles/enclosure/finish because of how much I have learned about my own tastes which has driven new designs and lots of scrapped MDF. I love how things sound now but of course I have my eyes on other mids/woofers...such is the audio addiction.

 

[planet10]

...and lots of scrapped MDF

And even more once you discover that MDF is not all that great a speaker building material

dave

 

[wesayso]

I'd look at this thread for some inspiration:
http://www.diyaudio.com/forums/multi-way/142015-my-open-baffle-dipole-beyma-tpl-150-a-118.html#post2922246

Another woofer worth considering might be the SB Acoustic Satori.

But it might be easier just to get a Danley setup and be done with it .
Have you seen what they do?
Check out: https://www.youtube.com/watch?v=JceVrR1nR2Q

 

[sreten]

Hi,

Its an awful amount of money for something that is probably total
overkill, and IMO will have a lot of design issues that as a novice
you are probably blissfully unaware of. Not recommended.

rgds, sreten.

 

[Generic George]

I am still looking for a one that you guys might recommend.
I have also heard there is a "thump" noise for behringer units.

I believe this one is considered adiquate

Dayton Audio UMM-6 USB Measurement Microphone* 390-808

I know there is a thump issue with the MiniDSP units, but I don't recall seeing any similar issues with the Behringer units. Most pro-amps have some sort of max vol limiters that is I believe intended to protect against such things.

I don't think I'll be maxing out the amps on the XPA-1s I'm waiting for the Gen 2 to come out with 60 watts of class A. I think I won't come anywhere close to audible distortion

Unless you have extremely high efficiency speakers (100+db@1w) where the efficiency is close to the S/N ratio of the amp, if you have audible distortion your amplifier is busted.

Class A amps are VERY large and VERY heavy and waste a LOT of power. None of which are admirable traits IMHO.

So should I buy these drivers to try in a small 2 or 3 way bookshelf or floor standing speaker first?
I know that line arrays are very different though, but at least I know what they sound like in different configurations.

A line array is a very different kind of speaker than a 2 or a 3 way conventional speaker. It really isn't going to tell you something useful about that.

If you do it, do it because you need the experience and practice with the little quirks and tricks of speaker building and/or you want some surround speakers.

I currently have a pt-7030 which is very good compared to my previous Yamaha. I currently have my Parasound A21 as the AMP. It sound is clear and almost 3D?

I would love to know how an amp without DSP makes sound "3D". If your amp is changing what you are hearing, it's not working properly. The purpose of an amp is to amplify a signal, not going and screwing with it (well at least if it's not a DSP amp..).

I'm not really sure as to what electronics you think I should get. My mind is definitely set on getting MICs for calibration and then Dirac in February next year with the new pre/pro.
I will still need a recommendation so I can look up these things...

Personally, I would definitely wait until people have had some of the XMC-1s in their hands long enough to see how well they actually work. Emotiva makes some great amps and decent speakers, but their track record on Pre-pros is... not inspiring of confidence.

I have noticed Rick has quite a few line arrays, obviously I cannot even compare to him since he does it as a living and acquiring knowledge/experience from using so many drivers. I have seen his Tempestas as well with the accuton drivers. He would probably have more experience then most people on here... I still want his raal+scanspeak Line array. But I also want to learn as well and understand why something is implemented. That's why I'm here right? How much does he generally charge? Does he explain why something is done a certain way?

As to what he charges, you should ask him that. Mine was a relatively straightforward 3 way wt an active crossover. That's a much easier thing to set up than a conventional crossover and much easier to experiment and tweek with. I'm not sure what else may be involved in doing a line array, it could be a lot more work, it could be less.

He was very responsive to question when I asked him, but I already knew enough to be dangerous and that I didn't want to be putting the expensive drivers I wanted to be using in my unskilled hands.

I'm the kinda guy that wants every detail. Sorry if I'm asking too many questions.

You at least seem to understand that you don't understand, that puts you ahead of a lot of people who come here.

Some time ago I was told by Rick that a Line Array is better for my setup. I didn't ask him much since he's running a business.

As long as you respect the demands his business places on his time and aren't insisting that he respond instantly to a long email, I think he's willing to discuss with you what you want and where it's best to put your money.

He's got a web board for his company here that he talks about various projects he's working on and where people ask questions.
Selah Audio

 

[sreten]

Hi,

Its an awful amount of money for something that is probably total
overkill, and IMO will have a lot of design issues that as a novice
you are probably blissfully unaware of. Not recommended.

rgds, sreten.

Hi,

Just add to the above if your heart is set in a line array do
so by all means but it needs to be very well thought out.

You could do very much worse than building these :

An externally hosted image should be here but it was not working when we last tested it.

CBT36 Line Array Speaker Kit Pair 301-980

http://www.parts-express.com/pedocs/manuals/301-980-audio-artistry-inc-cbt36k-manual-9148.pdf

Add a couple of serious subs and your good to go.

A very sensible plan for a novice IMO.

rgds, sreten.