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-   -   The Quasar Array (8) LMS 5400 in (4) Dual Opposed Sealed Cabinets (https://www.avsforum.com/forum/155-diy-speakers-subs/1175273-quasar-array-8-lms-5400-4-dual-opposed-sealed-cabinets.html)

Health Nut 08-30-2009 01:19 PM

This thread will document the construction of the Quasar Array subwoofers, (8) LMS Ultra 5400 drivers in (4) dual opposed cabinets, two supermassive black holes fighting it out inside the indestructible enclosure.

Final specifications:

42"H x 23"D x 28"W external. 4 cm thick baltic birch (1.575" thick) for enclosure and interlocking shelf bracing. Covered by 1.3 cm (1/2 inch) of mitered Black Quartz stone. This yields a 5.3 cm (2.1") thick wall of baltic birch and quartz stone.

Vtotal = 11.09 cu. ft (314 liters)
Vb = 9.95 cu. ft (282 liters) (after drivers + bracing).

Qtc = 0.487
F3 = 50Hz

The design will incorporate the use of a custom Marchand Bassis which can push the output flat to 5 Hz. Given that a total of (8) LMS Ultra 5400 18" drivers will be utilized, the output in the single digits will be quite substantial.

There will be a sligtly lower Qtc due to the addition of a combination of Acousta-stuff and some acoustic foam.
LL
LL

mjaudio 08-30-2009 03:48 PM

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This is going to be nuts and give Robert Charles a run for his money.

Can't wait to see the final outcome.

Good luck.

Mike

Looneybomber 08-30-2009 04:32 PM

Let's hope he doesn't take as long to build it as Robert...wait, I have no room to talk. I still have an unfinished sub that I started before Robert.

Good luck HN

mjaudio 08-30-2009 04:41 PM

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His longest wait will be for the 8 LMS 5400, hopefully TC Sounds will crank these out at least by the expected December due date.

Health Nut 08-30-2009 05:32 PM

I should have the cuts made within 2-3 weeks. The CNC machine is amazing. I may use screws if I don't feel like having the patience for clamp only... I'll decide that once all the cuts are made.

The decisions to be made now are the binding posts and the choice of laminate which could be Quartz, Granite, Black Glass (I need to call Glass werks tomorrow), or Wilson Art laminate (or a combination of these).

Corian is out because I checked out Corian, Sawnstone, Silestone, and all those Corian types: they look terrible in black and the black scratches white. Not a fan...

For binding posts, so far it seems essentially down to:

http://soniccraft.com/products/conne...ardas_ccgr.htm

or

http://soniccraft.com/products/conne...wbt_070211.htm


This thread will likely be dead October through November, but hopefully the cabinets will be finished by the end of September, that is my goal...

Helmutz88 08-30-2009 06:38 PM

All i can say is WOW. Your project is the dream for everyday's guys like me...can't wait till the new year, your HT will be severe.

Health Nut 08-30-2009 06:55 PM

I have new neighbors; ZERO complaints for two years, but new neighbor moves in and complains all the time... Looking forward to moving in one year or less...

Warpdrv 08-31-2009 06:20 AM

That is going to be a nice build health nut...
****What are your plans for amplification... ? ***nevermind saw your other thread***

I'll be in line for 3 LMS's when they finally come out myself, its going to be a long wait.

Nuance 08-31-2009 03:39 PM

^ But well worth it!

DonoMan 09-01-2009 09:46 AM

Quote:
Originally Posted by Health Nut View Post

I have new neighbors; ZERO complaints for two years, but new neighbor moves in and complains all the time... Looking forward to moving in one year or less...

Instead of complaining, your old neighbor moved away. That's how much you bothered him!

Health Nut 09-01-2009 11:00 AM

No, he died actually...

brandonnash 09-01-2009 12:33 PM

I read your other build was pretty massive too. Do you have a link to it or just some pics and description?

Health Nut 09-01-2009 03:25 PM

I'm going to have to sell the Black Hole Subs to make room for the Quasar Array...

I have my original design on paper which I dug out of the file cabinet and I can describe everything perfectly, but the build pictures which showed the construction have been lost I think... I had them all uploaded to a (now defunct) ISP, and did not have them backed up... When the ISP went away, I kicked myself...

Essentially, they are similar in that they used 1.25" marine plywood all the way around, except for a double laminated layer for a 2.5" thick baffle. All crossbracing used the same thick Marine plywood. The ports were made in 10" diameter from a custom plywood cylinder place. They have the $200.00 WBT binding posts and Kimber Kable internal wire (whop de do, I know, ... but I got that stuff at dealer cost). They used the Seismic 8196 drivers with honeycomb Kevlar cones and the Fs droped closer to 16 Hz. Essentially they were much improved Aura 1808 drivers.

They are tuned to 14 Hz, with 10" diameter ports. The port speed is rediculously low... The size requred to make this happen was 28" W x 45"H x 44"D There are four Black Hole subwoofers, I tend to stack them to make two subwoofers (similar to Wilson XS... but much better of course!)

mjaudio 09-01-2009 03:31 PM

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That Black Hole sub sounds insane

I heard a pair of Wilson XS subs so I know these are killer.

What are you going to sell them for?

Health Nut 09-01-2009 04:07 PM

Something reasonable...

LTD02 09-05-2009 04:36 PM

looking forward to your build. should be some interesting lessons learned along the way for all.


Health Nut 09-18-2009 08:49 AM

1) The wood has arrived. I'm trying to coordinate a method of pickup and delivery. Even though it is now closeby, the pickup hours are during weekday work hours only. Shipping weight: 1900 lbs.

2) Have committed to buying Caeser Stone, Absolute Noir. This Quartz material can be special ordered in 1 cm thickness which will make for a beautiful, rugged, and rigid laminate, however, will be reasonably light.

http://www.caesarstoneus.com/catalog...m?ProductID=65

Lead time is 2-3 months for special order.

3) Have both the CNC shop, SF Woodturning, as well as a Stone Shop ready to go, all estimates completed. I shopped hard for the past month to get the pricing and quality people I need involved on making these cabinets.

4) Binding posts and internal wire are here as well. I will be using 2 pairs of binding posts per enclosure, it simply makes it easier.
LL

penngray 09-18-2009 08:57 AM

Quote:
Originally Posted by Health Nut View Post

No, he died actually...

You killed him with HUGE BASS!?!?!!


Health Nut 10-03-2009 12:56 PM

I finally got a chance to stop over to SF Woodturning yesterday after work to take a look at the 4cm thick (1.575") Baltic Birch plywood. We also reviewed the cutting schedule which will also feature dado cuts for the cross bracing, making for a nice assembly. Other details such as recessing the binding posts as much as possible so that the red and black inserts are completely flush with the cabinet to allow the least amount of wood to be removed from the inside around the binding post.

The CNC machine will obviously do the work fast. It looks like the wood will be cut next weekend or the weekend after. Following which assembly will start.

From what it looks like, it will be about 8 weeks until both the TC Sounds drivers are available and the 1/2" Caeser Stone will be available. Apparently the Caeser Stone is 1.3 cm thick (1/2") not 1.0 cm as previously mentioned. Nonethless, a significant weight reduction over typical quartz offerings of 2 cm and 3/4" offerings.

One of the reasons I did not mind using 1.575" vs. 1" Baltic birch is that the final width and depth (footprint) were not going to change regardless of the thickness. The depth is simply what is required for the width of the driver (side firing dual opposed). The width of the subwoofer is the minimum required so that the dual opposed drivers had the necessary space between the motors. The only real variable has always been the height. Given the Qts of these drivers, it is so easy to achieve a 0.5 Qtc box. The only real consideration was airspring disortion and Qtc. Since height was never a concern, I would have been fine with anything up to 45". 42" height worked out great as noted in the specs. The Laminate will add 1" to the height (top and bottom), 1/2" to the depth (back not being covered in quartz), and 1" to the width. The drivers are going to be recessed 0.2" into the baltic birch given the 0.5" thickness of the Quartz.
LL
LL
LL

Warpdrv 10-03-2009 03:02 PM

Recess the drivers a bit deeper.... The Gasket around the drivers is at least 1" thick, I'll have to measure when I get home, I used 3/4" baltic birch as the outer and inner baffle, and the gasket and surround is still sticking out a good amount, and if you plan on making grills, then they will have to be pretty thick themselves with the excursion possibilities of the LMS...

Mike Hurd (Thanks Mike) brought my 2 new to me LMS's yesterday and we got them installed.... ended up not using the gasket, as my cutout was a touch oo small from the Mal-X's mounting... I made it too tight - we struggled with that with the gasket on... But back to my point... I can always make more boxes, but I will certainly go with a deeper recess - maybe 7/8 - 1" I always use a foam weather seal under the mounting, to assure no leaks, and that also adds to the depth...
Rubber Gasket is 3/4" depth - after measuring...

Just one mans thought.... It makes for a real nice transition for flush mounting and not having the driver stick out...

Warp

LTD02 10-03-2009 04:18 PM

Quote:
Originally Posted by Health Nut View Post

The only real consideration was airspring disortion and Qtc.

curious, how did you determine acceptable airspring distortion?

btw, that 1.5" bb is badass.

ssabripo 10-03-2009 04:48 PM

haven't been around much, but subscribed!

sounds like a great project...looking forward to your updates.

spanish68 10-03-2009 08:26 PM

I agree, that's a great project, a lot of money involved and time consuming but in the end, I'm sure it will be well worth it.

Health Nut 10-04-2009 12:28 PM

I was told, in general, that keeping the total displacement of the driver (SD x xmax x 2)to less than 5% of the total air volume keeps ASD effects mitigated. I believe there is a more specific forumla somewhere, Ricci mentioned it. I'm sure it is one of those that I knew at one time but forgot, like a lot of things. In any case, I'm just not used to modeling anything like the LMS 5400 in a sealed enclosure. I'm never afraid to build a big box. Since I always build sealed enclosures to a Qtc of around 0.5, thinking about airspring distortion was soemthing I never really had to think about. Not that it is anything major anyway... It is just that the box required to reach a 0.5 Qtc for the LMS 5400 is so small and the xmax so large, it was just something that caught my attention. You obviously don't want to go too big since you lose power handling; you also have to somewhat consider the possibility of subjective sounds of box Qtc, although I'm not quite so sure one can hear the difference if I were to design a box for 0.7 or 0.5. Regardless, if sound quality is the only objective, which in this case it is, you may as well make the box 'big'. Then we also take into consideration that Qts of the driver can rise about 20% when it gets really warm... So when you consider ASD, Qtc, and warming voice coils, it amounts to designing the box to be around Qtc of 0.5 as a general goal, in my opinion... The only other thing to consider are box modes less than 200Hz. The maximum dimension, the internal height in this case is the longest dimension = 38.85", so not an issue.

Health Nut 10-04-2009 12:44 PM

Quote:
Originally Posted by Warpdrv View Post

Recess the drivers a bit deeper.... The Gasket around the drivers is at least 1" thick, I'll have to measure when I get home, I used 3/4" baltic birch as the outer and inner baffle, and the gasket and surround is still sticking out a good amount, and if you plan on making grills, then they will have to be pretty thick themselves with the excursion possibilities of the LMS...

Mike Hurd (Thanks Mike) brought my 2 new to me LMS's yesterday and we got them installed.... ended up not using the gasket, as my cutout was a touch oo small from the Mal-X's mounting... I made it too tight - we struggled with that with the gasket on... But back to my point... I can always make more boxes, but I will certainly go with a deeper recess - maybe 7/8 - 1" I always use a foam weather seal under the mounting, to assure no leaks, and that also adds to the depth...
Rubber Gasket is 3/4" depth - after measuring...

Just one mans thought.... It makes for a real nice transition for flush mounting and not having the driver stick out...

Warp

Hopefully Kyle will put his input here and give his opinion based on the updated version of the LMS 5400 drivers.

noah katz 10-04-2009 07:37 PM

"You obviously don't want to go too big since you lose power handling;"

This doesn't make sense in the context of your intended usage.

Smaller box increases excursion-limited power handling, but at the expense of LF output; it limits excursion, so how could it be otherwise?

Also, power requirement is reduced as well, since the air spring is not as stiff.

With the same signal, a smaller box gives less low bass and a hotter voice coil.

It makes a lot more sense to reduce the excursion w/a HP filter.

And it's actually only true for excursion-limited power handling; thermal is higher because higher efficiency converts more power to sound.

Ricci 10-05-2009 10:55 AM

Actually I would not even bother to use the rubber gasket that comes with the drivers. They tend to leak. That's just me though.

mjg100 10-05-2009 02:31 PM

Quote:
Originally Posted by Health Nut View Post

No, he died actually...

You killed him with SPL.

mjaudio 10-05-2009 03:30 PM

1 Attachment(s)
Quote:
Originally Posted by Health Nut View Post

No, he died actually...


Quote:
Originally Posted by penngray View Post

You killed him with HUGE BASS!?!?!!


Quote:
Originally Posted by mjg100 View Post

You killed him with SPL.

You guys are killing me

Warpdrv 10-05-2009 06:09 PM

Quote:
Originally Posted by Ricci View Post

Actually I would not even bother to use the rubber gasket that comes with the drivers. They tend to leak. That's just me though.

I think it add's a nice look, but there are certainly ways as Bosso has come to show us... decorative trim rings can definately be an option, which Mike Hurd had mentioned as well, that just may be the way I think I may go...

Kinda partial to brushed stainless myself...
Which means you would need to rethink the depth again at that point...

With my 3/4" depth and no gasket plus crushed gasket I just measured you have 1/4" to flush... or so - I don't have a micrometer in my hands while the Packer game is on


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