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post #211 of 270 Old 06-09-2014, 08:57 PM
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Quote:
Originally Posted by Mark Seaton View Post

... with a 20dB/division vertical scale and wide aspect image. rolleyes.gif

The graph is smooth, but is hard to make any useful interpretations at that scale. Not arguing with the other statements between box types/sizes, but while it's mentioned the 13 cu.ft. each of the ported boxes, how large is the modeled sealed box? In many cases you can fit 2 or more sealed subs in the space of a big ported box. It then comes down to how much space vs. money is available for the application.

I'm mentioned many times before that I made an honest mistake when I took the measurement and forgot to rescale it, so thanks for rolling your eyes at the graph....lol

I could fit two stacks of three sealed drivers for less space then what my four subs take up, but of course I would have had to spend another $1500 between two more UXL-18's and an amp to power them. For the $3000 that it cost me in total to build the four subs that I have, I would find it hard to do much better for less then $3000.

Once I have the second two up and running this week I'll try to get some better measurements with the first going and then all four. I'm very positive I'll be able to have a nice flat curve before I add a bit of a house curve.
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post #212 of 270 Old 06-09-2014, 08:58 PM
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Quote:
Originally Posted by chalugadp View Post

Joe,
When did u run that graph ?

That graph was taken about a week after you were over.

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post #213 of 270 Old 06-09-2014, 09:32 PM
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What about a strong 18" driver with two or three 15" passive radiators? I think that would keep the box size smaller, cut down on some internal bracing, no worries about assembling the port properly or having it take up 1.25cuft of volume inside the box, chuffing, etc.
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post #214 of 270 Old 06-09-2014, 10:41 PM
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I'm thinking of building my first sub and would appreciate some input. Currently running a hsu vtf3 turbo. It's great but I want to go lower with more output. I'm trying to keep it cheap, around $500 with or without the amp. This will likely be used as an end table next to the couch. I'm thinking...

2 SI18s in a dual opposed 8-10 cuft box. If I wanted to make it pretty and stain it, what wood should I use?

Maybe inuke 6000dsp? Could I run both subs off one channel in case I decide to build a second?

It was suggested to me to run about 1000w into each sub.

Any help is appreciated!
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post #215 of 270 Old 06-09-2014, 11:00 PM
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Quote:
Originally Posted by ambesolman View Post

I'm thinking of building my first sub and would appreciate some input. Currently running a hsu vtf3 turbo. It's great but I want to go lower with more output. I'm trying to keep it cheap, around $500 with or without the amp. This will likely be used as an end table next to the couch. I'm thinking...

2 SI18s in a dual opposed 8-10 cuft box. If I wanted to make it pretty and stain it, what wood should I use?

Maybe inuke 6000dsp? Could I run both subs off one channel in case I decide to build a second?

It was suggested to me to run about 1000w into each sub.

Any help is appreciated!

Pretty tough to do it for that buget, the amp alone with set you back $400 and two SI 18's will also be around $400 shipped.

For the cost of the lumber it would probably just be cheaper to buy the dual opposed 18" flat pack from Erich.
http://www.diysoundgroup.com/subwoofer-flatpacks-2/dual-opposed-subwoofer-flat-packs/8-dual-flat-pack.html

$90 plus shipping is pretty cheap.

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post #216 of 270 Old 06-10-2014, 12:06 AM
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Quote:
Originally Posted by dominguez1 View Post

It was...but my math was wrong. Looks more like a 15db rolloff...which falls out of the 'drop off like a rock category' smile.gif

15dB? its not even 10dB, I'll try to get some better measurement's over the next week and post my graphs along with them being scaled correctly smile.gif

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post #217 of 270 Old 06-10-2014, 05:05 AM
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Quote:
Originally Posted by jbrown15 View Post

Pretty tough to do it for that buget, the amp alone with set you back $400 and two SI 18's will also be around $400 shipped.

For the cost of the lumber it would probably just be cheaper to buy the dual opposed 18" flat pack from Erich.
http://www.diysoundgroup.com/subwoofer-flatpacks-2/dual-opposed-subwoofer-flat-packs/8-dual-flat-pack.html

$90 plus shipping is pretty cheap.
You have to order two of those so the price for that flatpack is $180.

From that page:
Quote:
NOTE: The actual price of this flat pack is $180. It's shipping weight is 99lbs and must be shipped in 2 packages. The problem is that the shopping cart program and FedEx will not calculate the shipping correctly on any package weighing over 70lbs. To solve this I made the price 50% less, and the shipping weight 50% less. So if you want one flat pack, please enter '2' for the quantity and it will calculate shipping correctly for the 2 packages, and give you the end price of $180. If you want two flat packs, please enter '4' for the quantity and it will calculate everything correctly. I will likely send you an email to confirm shipping amounts, but it should be fairly close. If shipping ends up being less, I will refund your money.
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post #218 of 270 Old 06-10-2014, 08:18 AM
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Quote:
Originally Posted by jbrown15 View Post

Pretty tough to do it for that buget, the amp alone with set you back $400 and two SI 18's will also be around $400 shipped.

For the cost of the lumber it would probably just be cheaper to buy the dual opposed 18" flat pack from Erich.
http://www.diysoundgroup.com/subwoofer-flatpacks-2/dual-opposed-subwoofer-flat-packs/8-dual-flat-pack.html

$90 plus shipping is pretty cheap.

It's $180 but it looks pretty nice. Would it take a stain or just paint? Something that big in my livingroom would be preferable if it was anything other than a big black box.

How about vinyl wood grain to wrap it with? Anyone done that?
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post #219 of 270 Old 06-10-2014, 08:48 AM
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Quote:
Originally Posted by ambesolman View Post

It's $180 but it looks pretty nice. Would it take a stain or just paint? Something that big in my livingroom would be preferable if it was anything other than a big black box.

How about vinyl wood grain to wrap it with? Anyone done that?

Well you probably wouldn't stain it as it's MDF, but you could paint it or if you wanted to try to make it look really nice you could pick up some paper backed wood veneer and spray glue and veneer the sub and then stain the veneer.

http://www.parts-express.com/band-it-cherry-veneer-24-x-96-paper-backed--260-050
d
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post #220 of 270 Old 06-10-2014, 08:49 AM
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Quote:
Originally Posted by in3rtia View Post

You have to order two of those so the price for that flatpack is $180.

From that page:

My bad, that's what I get for only glancing at the price and not reading the bold red text....lol

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post #221 of 270 Old 06-10-2014, 09:19 AM
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Originally Posted by jbrown15 View Post


15dB? its not even 10dB, I'll try to get some better measurement's over the next week and post my graphs along with them being scaled correctly smile.gif


If anyone wants to, you can open a saved measurement sweep, rescale as desired, and save as a picture.


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post #222 of 270 Old 06-12-2014, 12:13 PM
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post #223 of 270 Old 06-12-2014, 02:37 PM
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Quote:
Originally Posted by Peterc613 View Post


You need to use [img] and [/img] before and then after the URL link to embed the picture at the right size.

I wish this was easier. New AVS sucks for posting pictures

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"Too much is almost enough. Anything in life worth doing is worth overdoing. Moderation is for cowards."
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post #224 of 270 Old 06-12-2014, 04:00 PM
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I've been watching the debate on this thread with keen interest. As many of you know, I started out planning on saving up for dual JTR Captivators to go with my DTS-10 and have been trying to become comfortable with DIY as a viable alternative. If I had a dedicated theater room, I'd build a wall of inexpensive DIY subs with iNukes to match or outperform the Captivators. However my theater is part of a nicely decorated multipurpose family room in a very large 10,000cf open floor plan. There are only two spots to add new subs and I must live within those limitations. It's not about lack passion or commitment, it's just practicality.




I've spent enough money over the years on the rest of my system that I don't want to skimp now on the rear subs. That's why the Cap's appealed to me - relatively small (compared to giant DIY boxes), legendary SPL and extension (at all the AVS shootouts), AVS reviews for tight bass (to match my electrostats), good resale value (when they do come up used, they're "Gone in 60 Seconds"), simple decision process (save, buy, move on to improving other parts of my system). The only downside is they're very expensive (read: takes longer to save for) and a matched pair seldom if ever comes up used for local purchase in Los Angeles (read: impossible).

At first I looked at the 24"x24"x24" Marty Cube with a UXL-18 but wasn't convinced a pair would give me the same performance as a pair of Cap's. Then I looked at Eric's new Stonehenge sub, but at 30"x30" it would block the HVAC main return vent, and at 16" deep it gave up performance I could get in a thicker sub for which I have the clearance. The 24"x24"x40" MiniMarty was too tall to fit under the rear speakers, so I modeled bigger variations of the Marty Cube to get more performance and PM'ed LDT02 for help. He responded with a 8.5cf design at 32"x32"x21" which was spectacular but unusable as anything over 27-29" wide still blocks my HVAC return:



I also started a campaign to get my wife comfortable with ever larger DIY enclosures by stacking some small boxes around the existing rear subs. First I got up to 24"x24"x30" and she didn't object. Then I added 2 more inches for height to 32" and she didn't balk. Eventually, I modeled a 24"x24"x32" enclosure in WinISD and talked to chalugadp about building a version coated in veneer. I showed her a picture of his lemans build in teak and she thought it looked OK:









As we got acclimated to having the stack of boxes behind the sofa, I began to think she might accept something even larger with capabilities closer to the MiniMarty and equal the Captivator. I got two 27.5"x23.5"x32" boxes from the UPS store, placed some leftover 3/4" finished teak plywood on both sides for appearance and let her percolate without saying a word:





It's been two weeks with the 29"x24"x32" boxes behind the sofa. At first she frowned when she saw them, then eventually didn't react, and finally indicated she might be able to live with them assuming they were nicely veneered. I've also gotten more comfortable with their size and really don't think they look that bad behind the sofa when the lights are dimmed:





First, I wanted to get an idea of the performance gain, so I modeled the new 29"x24"x32" size against the Marty Cube (yellow) and Mini Marty (white) at three tuning frequencies between 17.5 to 19 Hz:



Second, I wanted to see if it was worth the additional size and expense to go with the larger approx. 8.0 cu ft (29"x24"x32" side port) over the smaller 7.09 cu ft (25.5"x24"x32" front port). The smaller sub is simpler to build and I already have a reasonable estimate from chalugadp to make it. The larger sub would require more effort, materials and shipping costs plus a reprice from chalugadp (if he's willing to do it). The larger 8 cubic foot enclosure should allow slightly greater SPL and deeper extension approaching the Mini Marty. I modeled both box sizes at 19 Hz for maximum SPL and 17.5 Hz for maximum extension, again compared to Marty Cube (yellow) and Mini Marty (white) for reference:

SPL




Port Velocity




Xmax




Obviously the 19 Hz tune comes the closest to the MiniMarty response curve. However my rear subs are so close to the L.P. that I may be able to benefit from some near field affect with 17.5 Hz tuning at the lower frequencies and not loose near field SPL because of wall/floor/sofa back boundary reinforcement.

Unlike a dedicated theater where one would try to optimize bass for EVERY seat in the room, what I really care about is optimizing bass at the primary listening position. My wife and I love cinema. We use our system to watch one (or more) movies almost every day, 365 days of the year. We often have friends over on weekends for a movie on Saturday nights but most of the time it's just us with the dogs. With 10,000 cu ft of space we're not going to get a lot of room gain. So the question becomes what direction for ports and drivers will optimize the LFE at the main listening position without creating a peak across the middle sofa where we usually sit.

The DTS-10 "mouth" can be configured to open corner loaded on the left or mid-wall on the right. The rear subs can be ported forward into the room or mirror-imaged into the small space behind the sofa for wall/floor reinforcement to maximize near field boundary response.

With the 24"x24"x32" front port Marty variation I don't have any choice except to turn them sideways facing each other along the back wall or face both into the room. I have read the discussion at Databass.com about how hard it is to measure off-axis response at 1 meter from a ported sub where the port and driver face different directions. It indicates that I might experience a null at the LP between the subs if both drivers and ports are facing into the room with the L.P. so close (about 1.3m) directly beside and between them.

With the 29"x24"x32" enclosure the ports could be configured to fire mirror imaged toward the L.P. while the drivers fire into the room. I was hopping that someone with more experience might know if I'm completely off base. Which of these scenarios do you think is best for my application?

Even Response



Maximum Gain



Response and Gain



Lastly, as the OP stated at the beginning of this thread, my goal is to build a PAIR of DIY subs that will match (or exceed) the SPL, extension, low distortion or linearity of a PAIR of JTL Captivators. If I can save some money doing it then DIY is the way to go. If the Cap is about the same performance in a much smaller 20"x22.5"x30" box, then ID is the way to go. I think at this point, I'm pretty far along the road toward DIY subs, just still working out the details before taking the plunge.

Calling LDT02….

Calling LDT02….

Come in LDT02...
Attached Images
File Type: jpg WinISD-1 Four Subs SPL 19Hz PDF_00001.jpg (113.2 KB, 173 views)
File Type: jpg WinISD-2 Four Subs SPL 17.5Hz PDF_00001.jpg (110.2 KB, 171 views)
File Type: jpg WinISD-3 Four Subs PortV 19Hz PDF_00001.jpg (93.6 KB, 169 views)
File Type: jpg WinISD-4 Four Subs PortV 17.5Hz PDF _00001.jpg (97.1 KB, 168 views)
File Type: jpg WinISD-6 Four Subs Xmax 17.5 Hz PDF_00001.jpg (113.7 KB, 168 views)
File Type: jpg WinISD-5 Four Subs Xmax 19Hz PDF_00001.jpg (112.8 KB, 168 views)
File Type: jpg WinISD-0 LDT02 Sub 17-18-19Hz SPL PDF_00001.jpg (97.1 KB, 173 views)
File Type: jpg Photo-0 Marty 25.5x24x32 in small boxes PDF_00001.jpg (36.4 KB, 171 views)
File Type: jpg Room Gain Calculator PDF_00001.jpg (30.1 KB, 8 views)
File Type: jpg Room diagram-1 Sub port-driver all-front + DTS-left PDF_00001.jpg (53.9 KB, 167 views)
File Type: jpg Room diagram-2 Sub port-driver all-side + DTS-right PDF_00001.jpg (53.1 KB, 167 views)
File Type: jpg Room diagram-3 Sub port-driver side+front + DTS-left PDF_00001.jpg (55.2 KB, 180 views)
File Type: jpg Photo-1 LDT02 back wall with old subs PDF_00001.jpg (41.8 KB, 174 views)
File Type: jpg Drawing-1 of Marty 25.5x24x32 PDF_00001.jpg (89.8 KB, 169 views)
File Type: jpg Photo-0 Marty Sub in Teak 24 x 24 x 32.jpg (36.7 KB, 168 views)
File Type: jpg Drawing-2 of LDT02 29x24x32 PDF_00001.jpg (91.8 KB, 169 views)
File Type: jpg Photo-2 LDT02 back wall with new subs side view PDF_00001.jpg (48.5 KB, 169 views)
File Type: jpg Photo-3 LDT02 Right rear sub PDF_00001.jpg (43.1 KB, 169 views)
File Type: jpg Photo-5 LDT02 back wall with new subs overhead view PDF_00001.jpg (49.6 KB, 170 views)
File Type: jpg LTD02 Post on AVS 32x32x20 PDF_00001.jpg (53.6 KB, 168 views)
File Type: jpg Photo-6 lemans 24 x 24 x 32 in teak PDF_00001.jpg (38.0 KB, 168 views)

Last edited by Peterc613; 06-12-2014 at 09:29 PM. Reason: picture issue
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post #225 of 270 Old 06-12-2014, 04:25 PM
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Man - trying to upload this post with pictures REALLY SUCKS !

AVS took a lot of my time before, but I thought it was worth it because I was having fun and learning a lot about DIY.

Now it's a pain in the ass to post anything beyond short comments and you have to click on all these cryptic attachments to learn what they are.
Attached Images
File Type: jpg Photo-2 LDT02 back wall with new subs side view PDF_00001.jpg (48.5 KB, 182 views)
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Last edited by Peterc613; 06-12-2014 at 04:53 PM.
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This new format sucks BIG TIME compared to the old format for posting pictures.
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Right fn hate it!
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Quote:
Originally Posted by Peterc613 View Post
I've been watching the debate on this thread with keen interest. As many of you know, I started out planning on saving up for dual JTR Captivators to go with my DTS-10 and have been trying to become comfortable with DIY as a viable alternative. If I had a dedicated theater room, I'd build a wall of inexpensive DIY subs with iNukes to match or outperform the Captivators. However my theater is part of a nicely decorated multipurpose family room in a very large 10,000cf open floor plan. There are only two spots to add new subs and I must live within those limitations. It's not about lack passion or commitment, it's just practicality.

[IMG]Attachment 112513[/IMG]

I've spent enough money over the years on the rest of my system that I don't want to skimp now on the rear subs. That's why the Cap's appealed to me - relatively small (compared to giant DIY boxes), legendary SPL and extension (at all the AVS shootouts), AVS reviews for tight bass (to match my electrostats), good resale value (when they do come up used, they're "Gone in 60 Seconds"), simple decision process (save, buy, move on to improving other parts of my system). The only downside is they're very expensive (read: takes longer to save for) and a matched pair seldom if ever comes up used for local purchase in Los Angeles (read: impossible).

At first I looked at the 24"x24"x24" Marty Cube with a UXL-18 but wasn't convinced a pair would give me the same performance as a pair of Cap's. Then I looked at Eric's new Stonehenge sub, but at 30"x30" it would block the HVAC main return vent, and at 16" deep it gave up performance I could get in a thicker sub for which I have the clearance. The 24"x24"x40" MiniMarty was too tall to fit under the rear speakers, so I modeled bigger variations of the Marty Cube to get more performance and PM'ed LDT02 for help. He responded with a 8.5cf design at 32"x32"x21" which was spectacular but unusable as anything over 27-29" wide still blocks my HVAC return:

[IMG]Attachment 112681[/IMG]

I also started a campaign to get my wife comfortable with ever larger DIY enclosures by stacking some small boxes around the existing rear subs. First I got up to 24"x24"x30" and she didn't object. Then I added 2 more inches for height to 32" and she didn't balk. Eventually, I modeled a 24"x24"x32" enclosure in WinISD and talked to chalugadp about building a version coated in veneer. I showed her a picture of his lemans build in teak and she thought it looked OK:

[IMG]Attachment 112209[/IMG]

[IMG]Attachment 112609[/IMG]

[IMG]Attachment 112617[/IMG]

[IMG]Attachment 112697[/IMG]

As we got acclimated to having the stack of boxes behind the sofa, I began to think she might accept something even larger with capabilities closer to the MiniMarty and equal the Captivator. I got two 27.5"x23.5"x32" boxes from the UPS store, placed some leftover 3/4" finished teak plywood on both sides for appearance and let her percolate without saying a word:

[IMG]Attachment 112649[/IMG]

[IMG]Attachment 112665[/IMG]

It's been two weeks with the 29"x24"x32" boxes behind the sofa. At first she frowned when she saw them, then eventually didn't react, and finally indicated she might be able to live with them assuming they were nicely veneered. I've also gotten more comfortable with their size and really don't think they look that bad behind the sofa when the lights are dimmed:

[IMG]Attachment 112657[/IMG]

[IMG]Attachment 112673[/IMG]

First, I wanted to get an idea of the performance gain, so I modeled the new 29"x24"x32" size against the Marty Cube (yellow) and Mini Marty (white) at three tuning frequencies between 17.5 to 19 Hz:

[IMG]Attachment 112177[/IMG]

Second, I wanted to see if it was worth the additional size and expense to go with the larger approx. 8.0 cu ft (29"x24"x32" side port) over the smaller 7.09 cu ft (25.5"x24"x32" front port). The smaller sub is simpler to build and I already have a reasonable estimate from chalugadp to make it. The larger sub would require more effort, materials and shipping costs plus a reprice from chalugadp (if he's willing to do it). The larger 8 cubic foot enclosure should allow slightly greater SPL and deeper extension approaching the Mini Marty. I modeled both box sizes at 19 Hz for maximum SPL and 17.5 Hz for maximum extension, again compared to Marty Cube (yellow) and Mini Marty (white) for reference:

SPL

[IMG]Attachment 112129[/IMG]
[IMG]Attachment 112137[/IMG]

Port Velocity

[IMG]Attachment 112145[/IMG]
[IMG]Attachment 112153[/IMG]

Xmax

[IMG]Attachment 112169[/IMG]
[IMG]Attachment 112161[/IMG]

Obviously the 19 Hz tune comes the closest to the MiniMarty response curve. However my rear subs are so close to the L.P. that I may be able to benefit from some near field affect with 17.5 Hz tuning at the lower frequencies and not loose near field SPL because of wall/floor/sofa back boundary reinforcement.

Unlike a dedicated theater where I'm trying to optimize bass in EVERY seat in the room, what I really care about is optimizing bass at the primary listening position. My wife and I love cinema. We use our system to watch one (or more) movies almost every day, 365 days of the year. We often have friends over on weekends for A Movie on Saturday nights but most of the time it's just us. With 10,000 cu ft of space we're not going to get a lot of room gain. So the question becomes what direction for ports and drivers will optimize the LFE at the main listening position without creating a peak across the middle sofa where we usually sit.

The DTS-10 "mouth" can be configured to open corner loaded on the left or mid-wall on the right. The rear subs can be ported forward into the room or mirror-imaged into the small space behind the sofa for wall/floor reinforcement to maximize near field boundary response.

With the 24"x24"x32" front port Marty variation I don't have any choice except to turn them sideways facing each other along the back wall or face both into the room. I have read the discussion at Databass.com about how hard it is to measure off-axis response at 1 meter from a ported sub where the port and driver face different directions. It indicates that I might experience a null at the LP between the subs if both drivers and ports are facing into the room with the L.P. so close (about 1.3m) directly beside and between them.

With the 29"x24"x32" enclosure the ports could be configured to fire mirror imaged toward the L.P. while the drivers fire into the room. I was hopping that someone with more experience might know if I'm completely off base. Which of these scenarios do you think is best for my application?

Even Response

[IMG]Attachment 112225[/IMG]

Maximum Gain

[IMG]Attachment 112233[/IMG]

Response and Gain

[IMG]Attachment 112241[/IMG]

Lastly, as the OP stated at the beginning of this thread, my goal is to build a PAIR of DIY subs that will match (or exceed) the SPL, extension, low distortion or linearity of a PAIR of JTL Captivators. If I can save some money doing it then DIY is the way to go. If the Cap is about the same performance in a much smaller 20"x22.5"x30" box, then ID is the way to go.

Calling LDT02….

Calling LDT02….

Come in LDT02...
Please start a build thread when you do decide what you are going to do and when you get started. I also love the approach you took with your wife and seeing if she has a negative response. Kinda made me chuckle a little bit.
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post #229 of 270 Old 06-12-2014, 07:48 PM
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Just a heads up you need to use the [img] and [/img] with the URL link between it- not the attachment.

Quote:
Originally Posted by Peterc613 View Post
Man - trying to upload this post with pictures REALLY SUCKS !

AVS took a lot of my time before, but I thought it was worth it because I was having fun and learning a lot about DIY.

Now it's a pain in the ass to post anything beyond short comments and you have to click on all these cryptic attachments to learn what they are.
I know your pain.

You need to use the URL from the pic. SO open the attachment in another browser or tab and copy it from the address bar

Really a terrible way IMO.

So your above post would be like this:




I pasted: http://www.avsforum.com/forum/attach...9&d=1402615641

But put [IMG] before and [/img] after it.

It's a two step process. First upload your picture as an attachment for which AVS will generate a URL link for that if it's a JPEG - then take that URL from your pic and put it into your post with the [img] and [/img]

Really crappy compared to the old forum. This should be simple stuff in today's modern world. I can upload a pic so much easier with tons of other stuff. It does not need to be so hard. I heard AVS is working on a fix for this.

-

"Too much is almost enough. Anything in life worth doing is worth overdoing. Moderation is for cowards."
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Thumbs up

Quote:
Originally Posted by Mfusick View Post
Just a heads up you need to use the [img] and [/img] with the URL link between it- not the attachment.



I know your pain.

You need to use the URL from the pic. SO open the attachment in another browser or tab and copy it from the address bar

Really a terrible way IMO.

So your above post would be like this:

[img]http://www.avsforum.com/forum/attachment.php?
attachmentid=112569&d=1402615641[/img]


I pasted: http://www.avsforum.com/forum/attach...9&d=1402615641

But put [IMG] before and [/img] after it.

It's a two step process. First upload your picture as an attachment for which AVS will generate a URL link for that if it's a JPEG - then take that URL from your pic and put it into your post with the [img] and [/img]

Really crappy compared to the old forum. This should be simple stuff in today's modern world. I can upload a pic so much easier with tons of other stuff. It does not need to be so hard. I heard AVS is working on a fix for this.

Let me give this a try….




Your right - it works THANKS!
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post #231 of 270 Old 06-12-2014, 09:15 PM
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OK - so now I know the new convoluted way to properly post pictures on AVS.

How do I set the size to small, medium or large so my posts don't look obnoxious and swamp someone's browser with a slow internet connection?

This whole thing reminds me of the bad old days when Ronnie was in the White House, Nancy was just saying no to drugs, and we had Radio Shack TRS-80 computers with 8 inch floppy drives running DOS. We upgraded to 286sx computers with ONE MEGABITE Hard Drives running Wordperfect and you had to meticulously enter all the hidden format codes in front and behind any text you wanted to highlight.



What happened to the "Science" in Audio Video Science?
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post #232 of 270 Old 06-12-2014, 09:45 PM
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Peter ,
I'm just finishing my new minimarty. I chose teak veneer in honor of you . will be finished in a couple of days.
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post #233 of 270 Old 06-12-2014, 09:47 PM
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Quote:
Originally Posted by chalugadp View Post
Peter ,
I'm just finishing my new minimarty. I chose teak veneer in honor of you . will be finished in a couple of days.


Good luck posting pictures!....lol

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post #234 of 270 Old 06-12-2014, 09:53 PM
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Going to create a dedicated google site. Will put a link in avs. Until they fix this downgrade
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post #235 of 270 Old 06-12-2014, 09:55 PM
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Lol. Downgrade is right.
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post #236 of 270 Old 06-12-2014, 09:57 PM
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Quote:
Originally Posted by chalugadp View Post
Going to create a dedicated google site. Will put a link in avs. Until they fix this downgrade


Its funny, my biggest complaint is the posting pictures thing. It was just so easy the other way. I could get use to everything else that is new, but I loathe the way to post pics right now.

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post #237 of 270 Old 06-12-2014, 09:58 PM
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Less pictures means less quality IMO

Picture is worth a thousand words.
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post #238 of 270 Old 06-12-2014, 10:03 PM
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I'm not even bothering to try. If they don't fix it soon they will lose a tonne of people.
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post #239 of 270 Old 06-12-2014, 10:28 PM
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after re-reading your post a few times, I suspect that most of your questions are answered by knowing that at subwoofer frequencies, the sound is not directional and "beaming" as you have presented it in your pictures, but extends from the subs more as concentric circles with the sound reflecting off the walls and ceiling as though you inflated a giant balloon at the point of your subwoofer.


there will not be a null in between the subs. the spl with the drivers aimed sideways or forward will vary a bit, but more from things like 1/4 wave reflections off the rear wall for forward mounted drivers. the direction of the port matters very little as the bass wave at 20hz for example is 56.5 feet long, so it is "everywhere" in the room even before it has left the subwoofer.


i would suggest trying to find an enclosure design that keep the port to about 36-40" or so but that can be pushed if these are mostly movie spl machines. the concern is the first port resonance. that can get close to the passband if the ports get too long.

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post #240 of 270 Old 06-12-2014, 10:32 PM
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"Its funny, my biggest complaint is the posting pictures thing. It was just so easy the other way. I could get use to everything else that is new, but I loathe the way to post pics right now."


yeah, the other editor was better.


not sure if this helps:


How to put an image in a post!


i figured that a whole crap ton of folks would be frustrated with the new (old) system, so tried to offer a little help.

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