And... We're Off! Dual 18" Sealed Sub Build
scubalab
Posts: 2,993
Well, I've been sitting on the Ultimax drivers since last Thanksgiving and the Crown amp since Last Spring. Finally ordered some additional parts from Parts Express, picked up over 400 lbs of mdf (2 sheets 3/4" and 2 sheets 1/2"), glue, screws, dowel rods (for internal bracing) primer and paint. Measurements nave been taken, dimensions calculated, cut patterns laid out, and saw ready to make the first cuts.
The end result will be two subs in 20" wide x 34" tall x 22" deep sealed boxes. Top, bottom, back and sides will be 1-1/4" mdf, front baffle will be 2" mdf. It'll basically be a box in a box. I'll build the inner box with 3/4" mdf. All joints glued AND screwed. Front baffle will be 1-1/2". Then I'm gluing 1/2" mdf around all sides, no screws, sanded flush on all joints, 1/4-round routed corners, primed and painted satin black (I FOUND SOME BLACK PAINT! Well it's technically not black... sorry). Plan to brace it internally with 3/4" dowel rods recessed and screwed to the sides.
The end result will be two subs in 20" wide x 34" tall x 22" deep sealed boxes. Top, bottom, back and sides will be 1-1/4" mdf, front baffle will be 2" mdf. It'll basically be a box in a box. I'll build the inner box with 3/4" mdf. All joints glued AND screwed. Front baffle will be 1-1/2". Then I'm gluing 1/2" mdf around all sides, no screws, sanded flush on all joints, 1/4-round routed corners, primed and painted satin black (I FOUND SOME BLACK PAINT! Well it's technically not black... sorry). Plan to brace it internally with 3/4" dowel rods recessed and screwed to the sides.
Post edited by [Deleted User] on
Comments
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Finally, slacker!"....not everything that can be counted counts, and not everything that counts can be counted." William Bruce Cameron, Informal Sociology: A Casual Introduction to Sociological Thinking (1963)
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Bite me Dan!
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Sides for inner boxes are cut!
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Very nice. I love my 18" passive sub.
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Calling if for the day. Big holes cut. They all line up great. Just hope the driver fits!
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Very nice. Are those Prototypes for me? lol.
Keep us posted on the progression._____________________________________________________________________________________________
Ethernet Filter: GigaFOILv4 with Keces P3 LPS
Source: Roon via ethernet to DAC interface
DAC: Bricasti M1SE
Pre/Pro: Marantz AV8805
Tube Preamp Buffer: Tortuga TPB.V1
Amp1: Nord One NC1200DM Signature, Amp2: W4S MC-5, AMP3: W4S MMC-7
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Subs: 2 - Rythmik F25's
IC & Speaker Cables: Acoustic Zen, Wireworld, Signal Cable
Power Cables: Acoustic Zen, Wireworld, PS Audio
Room Treatments: GIK Acoustics -
Very interested in your final product... expected F3??- Not Tom
"No, that's silly talk. Dude, you can't possibly be this audio dumb so quit the act." - Doro -
Give me a bit and I will get it for you. My wife is using my laptop so I can't pull up the WinISD simulation.
But it's around a 6 cubic foot box IIRC and a Dayton Ultimax 18" driver with 775 watts per driver.... until I convince him to double up the amps and bridge them to give each driver 2500 watts lol..."....not everything that can be counted counts, and not everything that counts can be counted." William Bruce Cameron, Informal Sociology: A Casual Introduction to Sociological Thinking (1963) -
"....not everything that can be counted counts, and not everything that counts can be counted." William Bruce Cameron, Informal Sociology: A Casual Introduction to Sociological Thinking (1963)
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shooting for music or HT first?- Not Tom
"No, that's silly talk. Dude, you can't possibly be this audio dumb so quit the act." - Doro -
Mostly (90%+) HT. Very little music on that system.
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@VR3
He decided on sealed due to the easy of building, the lack of a need for a highpass filter to protect the driver, and its a ton easier to simulate in winisd lol.
Given his room is fairly closed off he should get some decent room gain and his chairs are on risers so I'm hoping all that works in our favor.
Ideally large ported boxes would be best, however the other criteria dictated we go sealed.
I'm very hopefully he will be satisfied. If not I'm gonna have some egg on my face since I pushed him in this direction
"....not everything that can be counted counts, and not everything that counts can be counted." William Bruce Cameron, Informal Sociology: A Casual Introduction to Sociological Thinking (1963) -
Yep. I blame Dan if this fails!
In all seriousness, it doesn't take much to make me happy. I'm running an SVS cylinder sub now that I'm happy with. I can't imagine these won't top my current sub. My main goal was to build something concealed in the wall and I fortunately had the room for two! -
Nice, I run a very similar setup in my HT. 2 UM18s, both in 7cf enclosures and each powered by a bridged Crown XTi2002. They are used as end tables, so there's no lack of bottom end. My favorite demo piece is the into of Edge of Tomorrow, where is drops down to 10hz..just be careful on the volume. My only recommendation to you is, consider a second amp.
"He who fights with monsters should look to it that he himself does not become a monster. And when you gaze long into an abyss the abyss also gazes into you." Friedrich Nietzsche -
One more thing, consider Dutatex instead of spray paint. It's easy to use, there are no fumes, and it dries quickly, slowly becoming rock hard after a week. The nap of the roller will dictate the texture of the finish. I used a 14" wide, 3/8 nap roller from Lowes for a slightly raised texture and no lines between applications."He who fights with monsters should look to it that he himself does not become a monster. And when you gaze long into an abyss the abyss also gazes into you." Friedrich Nietzsche
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Thanks for sharing that Face. Someday, I'll likely upgrade to two separate amps (one for each sub), but for now, I think the 2500 should be able to drive the two 18's fairly well. My boxes are going to be a bit smaller at about 6 CF (probably a little more like 5.5 CF taking into consideration the bracing and the drivers.
I'm hoping to make a little progress on these this weekend. I'll update the thread with pics! My goal is to complete the build of the boxes, and with all the parts for the interior (3/4") boxes cut, I just need to assemble and build in the bracing. Ideally, I'm hoping to then get the 1/2" cut for the outer boxes. If all goes well, I'll get all the 1/2" sides glued over the 3/4", and it'll be ready to hit the corners with the router and ready for paint next week.
Parts for the cables (from Parts Express and Douglas Connection) have been delivered and are waiting for me at home. I also have some T Nuts from Stafast.com that should be delivered today. I've got no excuse to not finish these now.
Getting closer! -
One more thing, consider Dutatex instead of spray paint. It's easy to use, there are no fumes, and it dries quickly, slowly becoming rock hard after a week. The nap of the roller will dictate the texture of the finish. I used a 14" wide, 3/8 nap roller from Lowes for a slightly raised texture and no lines between applications.
I used this and love the results. Nice recommendation Face. -
Nice, I run a very similar setup in my HT. 2 UM18s, both in 7cf enclosures and each powered by a bridged Crown XTi2002. They are used as end tables, so there's no lack of bottom end. My favorite demo piece is the into of Edge of Tomorrow, where is drops down to 10hz..just be careful on the volume. My only recommendation to you is, consider a second amp.
Hehehe.... I may have also been telling him that too... mainly because I want to have him ripple the carpet on his basement slab with the bass hehehe.....
Also nice to see you posting @Face
"....not everything that can be counted counts, and not everything that counts can be counted." William Bruce Cameron, Informal Sociology: A Casual Introduction to Sociological Thinking (1963) -
I considered the DuraTex, but went with spray paint because of the cost difference. I figure if I'm not happy with the paint, I can always go over it with DuraTex, but it'd be much harder to go the other way around. Is there any difference between DuraTex and the roll on bedliner paint?
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I've got some work ahead of me. This was waiting for me when I got home this afternoon after being out of town teaching since Tuesday evening...
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One box (inner) just about done...
Front baffle dry fit and without front-to-back bracing...
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"....not everything that can be counted counts, and not everything that counts can be counted." William Bruce Cameron, Informal Sociology: A Casual Introduction to Sociological Thinking (1963) -
I don't see no zip ties around those dowel braces....
And I wanna see pics of how crazy you went with scre-wing it together lol...
*apparently screw-ing" is censored"....not everything that can be counted counts, and not everything that counts can be counted." William Bruce Cameron, Informal Sociology: A Casual Introduction to Sociological Thinking (1963) -
Just for you Dan...
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^^^ I hope you cut the excess tie straps off! I see people leave them all the time in automotive and it drives me nuts!2 channel:
Bryston 4B3, Bryston BDA3, Cary SLP05, Shanling CDT1000SE with parts conneXion level 2 mods, Nottingham analogue ace space 294, soundsmith Carmen MKii, Zu DL103 MKii, Ortofon MC 20 MKii, Dynavector XX2 MKii, Rogue Audio Ares, Core power technologies balanced power conditioner, Akiko Corelli power conditioner with Akiko Audio HQ power cable, Nordost heimdall 2, Frey 2, interconnects, speaker and power cables, Focal Electra 1028 BE 2, Auralic Aries Femto, Black diamond racing cones, ingress audio level 1 roller blocks, JL Audio E110 with Auralic subdude, Primacoustics room treatments.
Theater:
Focal Aria 926,905,CC900, SVS PB ultra x2. Pioneer Elite SC85, Oppo BDP93, Panamax M5400PM, Minix neox6, Nordost Blue heaven LS power cables. -
I will definitely cut them off! My OCD would not allow me to leave those ends in there! It would drive me nuts too.
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^^^ I hope you cut the excess tie straps off! I see people leave them all the time in automotive and it drives me nuts!
Beat me to it! Although my OCD would lead me to do it on both sides so its an X lol.....
And then maybe throw a brad nail or two in there or maybe a screw just because......"....not everything that can be counted counts, and not everything that counts can be counted." William Bruce Cameron, Informal Sociology: A Casual Introduction to Sociological Thinking (1963) -
Lots of good OCD here. Mine would dictate that the zip ties at the very least all be installed in the same orientation, or at least mirrored left/right. And snipped, of course.
Are the dowels friction/compression placed, or will they see glue as well, hot or otherwise?
Looks like a fun project. Sub'd. (ha. subscribed)I disabled signatures. -
PS
Not having any experience with sub or speaker building, are zip ties enough to prevent vibration of the dowels against each other, or would it be wise to place some little sorbothane pads between before zip tying? My luck would dictate that I'd be pulling the baffle off 5 minutes after firing up, to address buzzing rods.I disabled signatures. -
Lots of good OCD here. Mine would dictate that the zip ties at the very least all be installed in the same orientation, or at least mirrored left/right. And snipped, of course.
Are the dowels friction/compression placed, or will they see glue as well, hot or otherwise?
Looks like a fun project. Sub'd. (ha. subscribed)
LOL. It's funny how OCD differs in people Scott. Mine? I actually installed the zip ties in the same direction, but mirrored around the vertical centerline of the sub. And they will be snipped. I literally threw those on the dowels late last night just to shut Dan up, and it was too damn cold to run out to the garage to get the snips!
Great idea on putting something in between where they touch to keep them from rattling! I'll cut a little piece of the speaker gasket tape and wedge it in there. I'll also probably put another zip tie on each cross like Dan mentioned. Everything is very tight. The dowels are recessed in a 1/4" deep routed hole, glued, and screwed from the outside of the side walls. I should have taken pics of that along the way!
