Home Theater Forum and Systems banner

1 - 20 of 23 Posts

·
Registered
Joined
·
19 Posts
Discussion Starter #1 (Edited)
OK I've narrowed my sub choice down to Kevins new tempest. Its modeling up real good in winisd and everything posted looks great. I keep seeing around 120db in room on these plans. The tempest is also a perfect match for my dayton 1000watt stand alone amp I already have. I want to modify the slot port design for my home and have a few questions. I've bumped my dimensions up some from my original plans. I'm wanting to go 20" wide by 20" deep by 38" tall. Slot port and sub both down firing. Will be a tight fit on the bottom but should work. The port will be 18.5" wide by probably 2" or 1.75" depending on room. Around 32" long I'm going for around a 20hz tune. I've looked at lowes and I can get oak in the sizes I want for legs and table top. 1x4 legs v on each corner and a 1" think table top. I'll go with a cherry stain on the oak and poly and paint the mdf black. The oak will hide all my screws so I don't have to worry about a million clamps. My plan for now is for 4" legs. I will probably double the mounting and counter sink the sub 3/4". Is 4" enough clearance for the port off the floor? Figure it's plenty for the sub. Winisd show around 20 to 25m/s on the port air speed. That box is 7.23 cubic feet and after sub and port/bracing should still be a little over 6cf. Is there anything else I'm missing? I should be ordering my sub/Christmas present soon. I haven't mastered google sketchup yet so here's my sloppy paint version so you see what I'm thinking.
 

·
Registered
Joined
·
1,026 Posts
There is nothing wrong with that approach. If you have enough clearance for the driver, you will have enough for the port. You need to calculate from the overall diameter of the driver and make sure it isn't intruding upon your port dimensions. You may want to plan for some small rubber bumpers for the feet but the amp, the box size and the port all look appropriate.

Kevin Haskins
Exodus Audio
 

·
Registered
Joined
·
19 Posts
Discussion Starter #3
Thanks for the reassurance on the clearance. I thought that was enough. This will put my overall height real close to my paradigm monitor 11 mains. It should make for a really nice tall table for my wife to put stuff on and look good in the house. I was planning on some rubber or maybe some of those furniture slider things on the legs. The plans I'm drawing on paper show it will fit but be very close. I'll wait till I have the sub and lay it out just to make sure before I start cutting and building. I'm looking forward to building this after Christmas. Haven't built anything in a while. I haven't had a sub for way to long. This one should take care of my bass hungry needs and blow the old blown overworked paradigm pw2200 out of the water.
 

·
Registered
Joined
·
50 Posts
Kevin are there any considerations to mounting your drivers in a horizontal orientation? Does it affect tuning/maximum excursion at all? How about the Passive Radiators?
 

·
Registered
Joined
·
1,026 Posts
Kevin are there any considerations to mounting your drivers in a horizontal orientation? Does it affect tuning/maximum excursion at all? How about the Passive Radiators?
For the active drivers, there is no problem with any orientation, vertical or horizontal is fine.

For the passives, they have to be mounted such that the cone is on a vertical plane. You typically use lots of mass on a passive and if they are facing up/down, they will sag. Think of old ladies with large boobs. The heavier the mass, and the longer they sit, the more they stretch.

Kevin Haskins
Exodus Audio
 

·
Registered
Joined
·
19 Posts
Discussion Starter #7
OK I got my orders in. The Tempest should be on its way soon and some wire, binding posts, and black ash laminate form PE also. To bad I just get to check the order and give it away till Christmas. I'm still trying to figure out what freq. to tune the port to. The amp has the hp at 18hz so I thought I would go above that to get use out of the port. I've set it down to 17hz too and it stays flat at 118db in winisd till 30hz then starts a smooth roll off. This will be mostly for movies but I do listen music on the system when the house is empty. Can't wait to see the 15" beast that you made Kevin.
 

·
Registered
Joined
·
19 Posts
Discussion Starter #9
Well I got the sub in the other day and it is just plain massive. Dwarfs the paradigm 12. Hooked it up free air and played some old cheesy bass cds. Can't wait to put this in a box. A few of those low notes in those cds had to be pushing it close to xmax. I had my head down by the spider watching in awe to the dead silence. Had a strong punch and appeared to be pretty power hungry. Surprised everyone is going with 500w amps. May just be me cause I'm having to use LR audio cause the stupid paradigm fried my lfe output. Hopefully I can get to working on this box in January after I get all the parts back for Christmas.

Kevin if you get time could you take some pics of the shiva, tempest, mal, and mal21 lined up. Be cool to see the size difference between them. Give something to help judge size by for us with your "small" subs haaa.
 

·
Registered
Joined
·
1,026 Posts
Well I got the sub in the other day and it is just plain massive. Dwarfs the paradigm 12. Hooked it up free air and played some old cheesy bass cds. Can't wait to put this in a box. A few of those low notes in those cds had to be pushing it close to xmax. I had my head down by the spider watching in awe to the dead silence. Had a strong punch and appeared to be pretty power hungry. Surprised everyone is going with 500w amps. May just be me cause I'm having to use LR audio cause the stupid paradigm fried my lfe output. Hopefully I can get to working on this box in January after I get all the parts back for Christmas.

Kevin if you get time could you take some pics of the shiva, tempest, mal, and mal21 lined up. Be cool to see the size difference between them. Give something to help judge size by for us with your "small" subs haaa.
Well... the Tempest is one of my small subs. The M-18 & M-21 dwarf it. A Tempest just barely fits under the rim of the basket when you are sitting the two on the floor.

Kevin Haskins
Exodus Audio
 

·
Registered
Joined
·
19 Posts
Discussion Starter #11
Well after all the snow, rain, and freezing temps I finally got a chance to get started. I got most of the pieces cut. The port did crack for some reason though. I glued it back should be fine. Here's a couple pics.


I didn't cut any braces yet. I haven't decided how I want to do that yet. I also cut the port at 28" for a 21hz tune. Think it will suite me best. From the looks of things with work and weather it will be awhile before I can work on it again. What would everyone suggest for bracing? A long one running from top to bottom up the middle of the port or a couple squares horizontal across the box?
 

·
Registered
Joined
·
19 Posts
Discussion Starter #14
I think down firing will be fine. Work sucks and so does rain and having to build outside. I'm oncall this week plus it's march. Could have got a lot done last week but I blew money in Nashville watching the Murray State Racers win another ovc title. Now to take out Vandy. Plus the Cats are on a wait till the last minute to do something roll.

The glue is PL Premium. The horn box builders seem to love it. I thought I would give it a try. That crack held after I took the clamps off so it must be pretty good. I may try to get some more pieces on this weekend in between ballgames.
 

·
Registered
Joined
·
19 Posts
Discussion Starter #15
I got the braces cut out and installed. Put the top and bottom pieces on also. Now just waiting for the glue to dry. All that's left is cutting out the port and speaker holes. Mount the binding post and try it out.


 

·
Registered
Joined
·
19 Posts
Discussion Starter #16
Finally fired it up tonight. Goes low. The lower the louder it gets. Bass cds get loud. I do feel its missing some upper punch but I don't have a lot of tweaking options. I need a test cd. Someone stole my old bass mekanic cd that had 20-99hz test tones. Bass I love you was pretty nice. Played the tank scene from saving private ryan and the pod race scene from star wars. Both were impressive. It sounds a lot better than my old sub. It doesn't strain like the old one did. I feel amp limited now. When I start getting the levels I want the clip light starts flashing a lot on my dayton 1000w rack amp. Really need some measuring software to see what I'm dealing with. I have no poly fill in now and it still sounds good. I was worried about box noise on the port side but haven't heard it yet. My kid will be gone tomorrow night so I will test a lot more and try more movies out. How much poly fill should I try? Its around 6.3 cubic feet and around a 21hz tune. I'm wondering if I'm feeling a the upper end lacking because all other boxes I've had were mid 30hz tuned. Sounds good so far and the house is shaking again haaaaaa.
 

·
Registered
Joined
·
790 Posts
I need a test cd. Someone stole my old bass mekanic cd that had 20-99hz test tones.
There are a few software based tone generators available. Then you can either use your PC as the source outputting via the S/C or save the tone(s), sweep(s) etc as .wav and burn them onto a CD.
 

·
Registered
Joined
·
19 Posts
Discussion Starter #18
Well here is a pic of it sitting where it will go.

I've been trying it out all weekend. It's loud and deeper than anything I've had before. Don't know how to say it but cleaner would be it I guess. Movie bass just sounds effortless from it. My old pw2200 sounded strained at loud volume. Now sometime I have to take it apart and make it look good, booo. I watched terminator salvation on it and the new star trek, wow. Tried several cds and it's sounding better the more I play it. Still trying to figure out how much poly fill to toss in. Kevin has 40oz on the 5 cubed box and 15% on the 6.35 which is what mine is close to. I need to go buy the oak now and get it ready to glue on. I guess I'll have to stain them on the box with the laminate on already. Will be a pain but maybe I can tape the laminate off without messing it up. For those worried about port size and chuffing I don't think I've heard it yet. The paradigm made noise a lot during movies. It was hard to hear over the floor vibrating bass that the pressure was starting to hurt my ears on terminator. The port is only 18.5 x 1.75 x 21 with 1/2 round over on both ends. I can also say the 1" flush trim bit is my new best friend. Made the port cutout perfect along with my top and bottom plates.
 

·
Registered
Joined
·
19 Posts
Discussion Starter #19
Well I can't figure out the quote thing.


There are a few software based tone generators available. Then you can either use your PC as the source outputting via the S/C or save the tone(s), sweep(s) etc as .wav and burn them onto a CD.


But where can I find this? The few places I've looked haven't worked. I'm considering loading rew on my new laptop but not sure it will work right. I tried listing to music off the headphone jack and it sounded awful, bad echo and high pitch. Whats the best thing to use? I even looked for that old bass mekanic cd at some stores but no one had it. I could order it if all else fails but free sure is a lot better.
 
1 - 20 of 23 Posts
Top