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S.E.O.S.R. MEGA BUILD - Page 37

post #1081 of 1496
"I'd like to see a photo of the speaker with the baffle beside a grown adult, hard to really get an idea of how big they really are."

not sure which direction chop is headed, but here is the massive 5674 on the left with a seos 24 and quad 15's on the right.

post #1082 of 1496
Thread Starter 
I'll try to get one up tonight. You will be surprised when you see them next to a full size adult...I'm about 6'2" and 235lbs and they look huge next to me.
post #1083 of 1496
LTD lmao you just love photo-chopping smile.gif I already know the quad 15" is way too large for my space, but I am trying to convince myself I can do the dual 15"
post #1084 of 1496
That photo shop picture got me thinking and I just played around in PCD. If doing side by side woofers you'll wanna cross below 500hz at least. There's a giant null at 600hz and 45degrees. My one and only time doing side by side mids ended up being worse than PCD predicted too, so take that with a grain of salt.

Will the SEOS hold directivity down to 500hz? If it can, then it would make a great setup. There would be vertical nulls like crazy going MTM, which Chop's setup will have to address somewhat. Depends how far back he's sitting. Might be a benefit.
post #1085 of 1496
photo shop? i wish. i use ms word for all that farting around which is why they look so clumbsy. :-)

"If doing side by side woofers you'll wanna cross below 500hz at least. "

the crossover target is 450hz and that seems right looking at the frequency response and distortion plot for the coax driver.

"There would be vertical nulls like crazy going MTM..."

the speakers are going in a dedicated theater. if the speakers are placed properly, pretty much all ears should be on axis vertically and certainly far enough back for good summation. does mtm present any other problems in that scenario?
Edited by LTD02 - 10/1/13 at 1:19pm
post #1086 of 1496
Thread Starter 
Good comments tux, good question LTD.

So the seats will be at (approx) 12ft, 19ft and 26ft back.....they should all be in a position where sound to each is good I would think. If not, please correct me, I've been wrong plenty. The height variance will be something like...on axis in row two, 14" below in row one and 14" above in row three(relative to the waveguide center). This is with a WMTMW setup. I honestly had scrapped the idea of the side by side and quads, but if there is more benefit or less negative to that than the vert arrangement, I'm open to it. I honestly thought the vert would be easier to get right.
post #1087 of 1496
You should be fine like that. I agree the vertical is easier to get right. There will be a lot of vertical directivity, and it won't be matched to the WG, but that's not such a big deal in the vertical direction. Most people would say horizontal is much more important. So no, no problem IMO.

My SEOS10 WTMW has narrow nulls at roughly 30 degrees and 700hz and it's ok. It's technically bad, but vertically I can hear there's no ceiling reflection and this is quite nice. Horizontally, I can't hear it because I used it in the CC position about 15' from any side walls and sitting 10' away. So the reflected sound wasn't really heard in that case. Consider further this would occur very low in frequency for you (500hz or so) and the room is just starting to take over, it's even less of an issue. And considering people listen to crappy MTM centers all the time, a horizontal woofer arrangement wouldn't be nearly that bad. But you're certainly not trying to match the performance of a 6" MTM either tongue.gif
post #1088 of 1496
the tannoy vq have angled / recessed woofers to improve off axis radiation (i assume). came up in another thread. renkus heinz also has something similar.

not sure what imax speakers are spec for new construction, but here is a pic of one (12" woofers in that one).

seos 24 quad 15 mockup. :-)~






Edited by LTD02 - 10/1/13 at 3:24pm
post #1089 of 1496
Your photo shop skills keep getting better LTD02 biggrin.gif
post #1090 of 1496
any idea if woofers angled and inset like that radiate more or less as a single driver with a width of the opening or is it still two sources?
post #1091 of 1496
I'm not sure. The centers are closer. They're also already beaming on axis since they're physically angled. At 45d the one driver would be 90d and the other about 0d. So maybe it does act like one. I should experiment with that sometime. What are your thoughts?

EDIT - There's also gotta be some coupling effects like they're in a horn.
post #1092 of 1496
There's no comb filtering with angling two woffers like that? Overall dispersion will be better at the expense of some phase interaction issues ?
post #1093 of 1496
If those were 8" woofers, what type of angle do you think they'd be on? I can make up some test boxes with dual 8's or 10's.
post #1094 of 1496
Good question.

I don't recall ever seeing any such work examining these issues.

I wonder if EAW has any documented work in this regard. Their clamshell subs, SB2001(double 21) and SB1001(double 18) are so config'd, obviously the big difference is pass-band limited to 190hz up top. Their (2)21" is a tight V the entire cab merely measuring 33.5" wide x 22" high, resulting in nice tight packs, minimal frontal elevation.

Also, Bill Fitz sells crossfire tweeter arrays, MKtheater uses some IIRC. Point being I wonder what previous work was been explored prior to employing such an approach.
post #1095 of 1496
the specs and measurements are available in an xls file here (click on downloads on the left):

http://www.tannoypro.com/#Page=Downloads&Id=-1

this is the vx60. crossover point is a hair over 500hz.



the off axis, while smoothed, looks pretty good. only shown out to 40 degrees.

ha! there is the geddes on-axis hole! at about 3500hz, they boost eq for flat on axis response which goofs up the polar. tannoy needs a seos 24!

anyways, these are 12's i think, but it seems to work pretty well. is there something that would mess this design up that isn't showing up here?


Edited by LTD02 - 10/1/13 at 5:07pm
post #1096 of 1496
the polars around the crossover point don't seem to exhibit any weirdness either. maybe it kind of works.





..........

erich, i'm not sure that the angle depends on the driver size, if anything that would seem to impact the off axis response.

my intuition suggests a 90 degree would be a good start. any more than that and there may be a rising manifold like peak in the response?
Edited by LTD02 - 10/1/13 at 5:06pm
post #1097 of 1496
A pair of 12s with a close spacing and a top pass band of 500hz, even some stop band of say 700hz shouldn't have any nulls, so that's not a big surprise. But an interesting data point.

Nice call on the on axis hole smile.gif If listening with toe in, there might be some squak right there. SEOS for the win!
post #1098 of 1496
Thread Starter 
Quote:
Originally Posted by tuxedocivic View Post

You should be fine like that. I agree the vertical is easier to get right. There will be a lot of vertical directivity, and it won't be matched to the WG, but that's not such a big deal in the vertical direction. Most people would say horizontal is much more important. So no, no problem IMO.

My SEOS10 WTMW has narrow nulls at roughly 30 degrees and 700hz and it's ok. It's technically bad, but vertically I can hear there's no ceiling reflection and this is quite nice. Horizontally, I can't hear it because I used it in the CC position about 15' from any side walls and sitting 10' away. So the reflected sound wasn't really heard in that case. Consider further this would occur very low in frequency for you (500hz or so) and the room is just starting to take over, it's even less of an issue. And considering people listen to crappy MTM centers all the time, a horizontal woofer arrangement wouldn't be nearly that bad. But you're certainly not trying to match the performance of a 6" MTM either tongue.gif

Thanks, I though I had that right in my mind (that a quad WMTMW would be easier for me to make work). I keep fighting with the ideas of how each works with directivity and such..all new to me. When you say horizontal is more important, you mean the horizontal directivity right?? and that a vertical WMTMW arrangement will provide a better horizontal match with the waveguide?? Sorry, I'm trying to digest so much all at once.

Quote:
Originally Posted by LTD02 View Post

the tannoy vq have angled / recessed woofers to improve off axis radiation (i assume). came up in another thread. renkus heinz also has something similar.

not sure what imax speakers are spec for new construction, but here is a pic of one (12" woofers in that one).

seos 24 quad 15 mockup. :-)~






I have gotten to the point tonight where the only thing left to do on the dual 15 seosr main cabinets is attach the baffles. I also got two of the single 15 cabinets done for testing with different quad 15 arrangements. Hopefully I can get the other two singles done tomorrow night and be ready to move everything outside this weekend and at least get some measurements. We only have so much longer that the weather will cooperate. I figure if I leave the cabinets raw for now, in the interest of testing asap, I can fine tune the finish over the winter and take my time with the look...even though they won't get seen too often:)

The way the singles are made, I can test all sorts of different angles like shown above also. It scares the crap out of my to try, but what's the worst that can happen..I need some advice or need to keep trying or just go back to an easier to integrate design....the reward is bigger than the risk biggrin.gif
post #1099 of 1496
Horizontal is more important because we all are about a foot and a half in height the same, but seating can be 10' wide or more. Also, our ears are more sensitive to horizontal cues and reflections. Vertical is actually quite important in that its nasty. The less we hear the better. And what we do hear is hopefully attenuated a large amount. MTM is better for this.

MTM is earlier to get a directivity match because you don't have to deal with the nulls we've been discussing for two pages. There's no way you can screw up the directivity match to a 15" at 500hz.

Ya, I have a pair of 10" in modular cabs I was thinking of test to see what happens. It's raining like crazy here lately, and I think ground plane would be the best way to test this kind of thing. Ill try in my shop where I can get down to around 200hz, but I'm fairly busy lately. If you get to it first let us know how it goes. Outside would be best for this kind of excersize though.
post #1100 of 1496
Quote:
Originally Posted by ChopShop1 View Post

Thanks, I though I had that right in my mind (that a quad WMTMW would be easier for me to make work). I keep fighting with the ideas of how each works with directivity and such..all new to me. When you say horizontal is more important, you mean the horizontal directivity right?? and that a vertical WMTMW arrangement will provide a better horizontal match with the waveguide?? Sorry, I'm trying to digest so much all at once.

Yeah basically is better to have any nulls in the response from multiple woofers on the vertical axis rather then the horizontal axis as the listening area tends to always span further across the horizontal plane then it does vertically. Using a single woofers stacked vertically there are no nulls as you move off axis horizontally so there is no concern there. Only if you place then side by side will you run into trouble as you get a comb filtering effect off axis horizontally as frequency rises. The frequency at which that happens is determined by the CTC distance of the two drivers, mounting them cross firing in the baffle allows for a closer CTC. Playing around with the angle and taking off axis measurements would be the best way to figure out if the directivity of the SEOS-24 could be matched.

I had thought of doing something crazy like that back when you were thinking of using 4 woofers before you started cutting down the design. I still think it could be made to work out and would look really impressive biggrin.gif

Ah tux got to it first tongue.gif
post #1101 of 1496
Thread Starter 
Thanks guys, I'm finally starting to understand the foundation. In the beginning of this thread, I didn't have a clue. Not saying I know too much now, but at least my understanding of the basics is better. I started out thinking that more woofers side by side mean wider sound...little did I know it created problems from a width standpoint. It makes me laugh because I feel all smart in the audio realm when I walk into a BB, but when I'm in the diy section I feel like an infant.

I know it came up before Matt, maybe I just couldn't understand then redface.gif I am open to trying everything now, and modular cabinets will make it nice and easy..at least from a portability standpoint:D

I feel like I have leaned on you so much with the seosr project and all the other things you have going on, perfecting the seos12/td15 design for surrounds, etc. I don't want to dump any more on you now. I really hope I'm able to ask enough questions here and learn enough to work some of quad designs out at home. I'm smart enough to know I'm not that smart, so I'll take all the advice I can get biggrin.gif
post #1102 of 1496
Thanks EVERYONE. Thats what I was hoping to see. I was looking at keeping width down to a minimum and the angled woofers look like my ticket. Angled 12's wont really be an option though because they will be a lot smaller than the width of the SEOS 24". SO all this data is very helpful. I do have some NLW9300 15's on me now so I could slowly build an angled baffle and test that. Erich you and others will probably have a better testing setup that I.

I forgot all about the surrounds. How are those coming along? Are there any finalization's yet?

I think you should also do a video of you listening to your speakers for the very first time. The sheer enjoyment/shock would be worth watching. biggrin.gif
Edited by chrapladm - 10/1/13 at 8:50pm
post #1103 of 1496
Quote:
Originally Posted by LTD02 View Post


ha! there is the geddes on-axis hole! at about 3500hz, they boost eq for flat on axis response which goofs up the polar. tannoy needs a seos 24!

LTD02, there's a project you could really help with. You have a lot of good information on the SEOS and post bits of it in many threads. Would it be possible to consolidate that into something we can put on the website? Right now I have zero information posted on the waveguide itself because I'm not as 'technical' as you are. Nor do I know all the audio lingo. Fact is, for what we've created, the info on the site is extremely lame......thanks to me. rolleyes.gif

Could you start writing up the benefits of the SEOS? Technical stuff, why it works, how it works, what it does better, why the speaker designs are made the way they are, etc. You give a lot of great information on the forum, and I wanted to start taking notes over the past 6 months or so. But with all the projects I'm working with, it just hasn't worked out.

I don't really know where you would start. Most of your informative posts over the past few months have given some pretty good details. It would be great to consolidate that into one place.
post #1104 of 1496
Thread Starter 
Quote:
Originally Posted by chrapladm View Post

Thanks EVERYONE. Thats what I was hoping to see. I was looking at keeping width down to a minimum and the angled woofers look like my ticket. Angled 12's wont really be an option though because they will be a lot smaller than the width of the SEOS 24". SO all this data is very helpful. I do have some NLW9300 15's on me now so I could slowly build an angled baffle and test that. Erich you and others will probably have a better testing setup that I.

I forgot all about the surrounds. How are those coming along? Are there any finalization's yet?

I think you should also do a video of you listening to your speakers for the very first time. The sheer enjoyment/shock would be worth watching. biggrin.gif

Sweet! It will be cool to see this thread spark off some other new projects and take the SEOS based designs to a whole new level. I'm willing to guinea pig my stuff for testing as well, so keep that in mind. If there are other things folks want to do, with some of the same components, I'm happy to build cabinets to accommodate and test with. I could post the measurements, pics, etc and just let the help and advice come in from there.

The surround design is done!!! The xovers are upwards of a hundred bucks each, but it seems to be more than worth it. As the designer of both the Fusion Sentinel and this TD based surround, Matt believes that this new unit with upgraded xover is significantly better in many ways. The total cost isn't bad at all either....$250 woofer(with group buy we had) $75 DNA360, $25 seos12 and $100 xover. So $450 a piece plus materials or flat pack. With a sheet of BB and build your own, it's just over $500. I kinda put all me efforts into the seosr lately as far as cabinet building and so forth, so now that the surround design is done I'll get some of those cabinets built and give em' a listen.

Love the video idea! I think all you'll see is biggrin.gif:D:D:D I haven't even heard them yet and I can't wait to see the faces of everyone when we finally do a GTG and they make their public debut:D

Quote:
Originally Posted by Erich H View Post

LTD02, there's a project you could really help with. You have a lot of good information on the SEOS and post bits of it in many threads. Would it be possible to consolidate that into something we can put on the website? Right now I have zero information posted on the waveguide itself because I'm not as 'technical' as you are. Nor do I know all the audio lingo. Fact is, for what we've created, the info on the site is extremely lame......thanks to me. rolleyes.gif

Could you start writing up the benefits of the SEOS? Technical stuff, why it works, how it works, what it does better, why the speaker designs are made the way they are, etc. You give a lot of great information on the forum, and I wanted to start taking notes over the past 6 months or so. But with all the projects I'm working with, it just hasn't worked out.

I don't really know where you would start. Most of your informative posts over the past few months have given some pretty good details. It would be great to consolidate that into one place.

Erich, that's an awesome idea! These guys certainly do know their stuff! I think LTD has posted something useful in about every thread in the diy section.

You should also talk to Matt regarding the new TD15/dna360 seos12 design with the updated xover. Seems like the xover upgrade might make it a good SEOS Reference contender on the lower end of the price spectrum. It might creep a little bit higher in cost due to the slight increase on the TD woofers.
post #1105 of 1496
So the actual pro's & con's for having the woofers side by side are that; a.) you have a closet center to center distance, b.) better verticle directivity? The con's would be; a.) nulls in the horizontal axis as frequency rises, b.) comb filtering.

Do I have that right?
post #1106 of 1496
Instead of building test angled baffles, couldn't you just build two separate boxes? You could keep the drivers as close to the edge as possible, put them together at whatever angle you want to test.
post #1107 of 1496
Thread Starter 
Quote:
Originally Posted by sdaddy View Post

Instead of building test angled baffles, couldn't you just build two separate boxes? You could keep the drivers as close to the edge as possible, put them together at whatever angle you want to test.

That's exactly what I'm doing. The four single 15 cabs are just squares and can placed or angled however I want. The woofers are going to be mounted within 9/16" to the edge of the cabinet, so as close to each other as it's going to get. This way I can test vertical arrangement, horizontal arrangement, angled, etc.
post #1108 of 1496
If someone can figure out the angle used on those dual woofers, I'll get a box made up with the SEOS-15 or 18 and a BA-750.
post #1109 of 1496
Thread Starter 
Quote:
Originally Posted by Erich H View Post

If someone can figure out the angle used on those dual woofers, I'll get a box made up with the SEOS-15 or 18 and a BA-750.

What, no 24?? tongue.gif

Hopefully I'll be testing the angled ones in the next week or so. I'll post all the measurements, graphs, etc so they can be broken down and the collective suggestions can be implemented to see what works best.
post #1110 of 1496
Ya, hold up Erich. We already have the capability. Do the preliminary stuff first smile.gif
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