Jay481985 Posted February 2, 2006 Share Posted February 2, 2006 the rt-12d was designed for a corner but it can be placed anywhere. three sided box, I would go more with a trapezoid area. (1/2(B1+B2) X H) X the H (This is actualy height as opposed to the other H that was the height when looking above) How do you want it to look? ______ / \ / \ / \ ------------------- from above? Quote Link to comment Share on other sites More sharing options...
DrWho Posted February 2, 2006 Share Posted February 2, 2006 The RT-12d does not have to be positioned in the corner. The shape of the design however allows it to take up very little floorspace when it is installed in a corner (which is the purpose of its shape). As far as performance goes, you will have a lot less cabinet vibration because every driver is firing in a different direction. The only downside to the design is an internal amp needs to go on top of the enclosure. Though there is nothing stopping you from putting the amp outside of the cabinet either (which would be my preferred method). As far as calculating box volume, I wrote an excel spreadsheet to calculate all the dimensions (wrote it even before the RT-12 came out). I've been meaning to pretty it up a bit and take a few more things into account so if you're willing to wait I can get one sent to you. Running some quick numbers, a 7 cubic foot cabinet would have 3 faces that are 26" wide and 21" tall...making the total depth from the corner to the front face 23" long. Quote Link to comment Share on other sites More sharing options...
billyjoe72 Posted February 2, 2006 Author Share Posted February 2, 2006 "Running some quick numbers, a 7 cubic foot cabinet would have 3 faces that are 26" wide and 21" tall...making the total depth from the corner to the front face 23" long." I'm sitting here looking at a printout of the rt-12 and looking at the numbers you quoted and I am getting somewhat aroused[:$][] by the thought of starting it. I think I will mimic the rt-12 and go with the 2 pr's you pointed out. I really don't want to put the amp on top so I believe I will keep it out. Could I just build a nice pretty cabinet for the amp, run the wires. and be ok, or will there be some heat issues to deal with? Almost fully aroused now. [] This is the design I'm using. Ideas on braces for this? I was thinking 2 on each corner cut off connecting adjoining sides and something on top and bottom connecting all sides. Quote Link to comment Share on other sites More sharing options...
Jay481985 Posted February 2, 2006 Share Posted February 2, 2006 what about the amp on the wall side? the smallest wall parallel to the active woofer Quote Link to comment Share on other sites More sharing options...
DrWho Posted February 2, 2006 Share Posted February 2, 2006 As far as putting the amp in another enclosure, I would recommend a vent of some sort...perhaps even leaving a hidden face of the cabinet completely open. I can think of a bunch of ways to do this so it shouldn't be a big issue. One cool thing about going with this amp is that you could always build yourself a second identical sub and run it in parallel with the one you're building now. The amp will then see a 4 ohm load and split the 1000W output to the two drivers - yielding a 6dB increase in volume [H] And then you also get the added benefit of a more even soundstage (with a sub in each corner). As far as bracing, I would just reinforce all the vertical corners (making a very strong connection to the side panels) and then a few vertical braces in the middle going between the top and bottom. You won't have to go too overkill on this simply because triangles are very rigid shapes. And you also don't want to impede the airflow inside the cabinet (so that you can maximize excitating of the passives). One other tip...use T-Nuts to attach the driver to the enclosure instead of wood screws or something like that: http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=260-778 These will allow you to remove and reinstall the driver as many times as you want...which is a handy feature if you ever need to do any work inside the cabinet. One thing you might consider down the road is the addition of some damping material to the top and bottom panels so as to minimize the hollow box sound that might resonate out through the driver itself. Even with the resonant frequencies out of the passband of the driver, you are still going to get harmonics from the driver movement that could excite them...and these sounds will then resonate inside the cabinet and bleed their way out through the actual driver itself. At this point we are completely over thinking the process, but I thought I'd mention it just in case it presented its ugly head later on. Quote Link to comment Share on other sites More sharing options...
Jay481985 Posted February 2, 2006 Share Posted February 2, 2006 I personally like hurricane nuts over t-nuts which partsexpress also sells Quote Link to comment Share on other sites More sharing options...
billyjoe72 Posted February 2, 2006 Author Share Posted February 2, 2006 I figured the triangle would be pretty strong. I'm going to get started on it this weekend with the dimensions you all gave. It will be a long process. I usually work too fast on things but I'm going to take my time on this project. Plus I have alot going on right now. The worst that can happen is bad sound. The wood is cheap I can always rebuild another cabinet if it does. I'm sure it won't though. I rushed through my center channel when I built it. The little mistakes I see here and there are probably not noticed by anyone else though. You know how that goes. I don't think I'm going to double up any panels on it. But I may change my mind. Who knows. To be honest with you, I'm more worried about my surroundings rattling and driving me nuts.[] I figure if I use the arsenal, 2 passives, and the Dayton 1000 It should cost somewhere around $700. I like the idea of having two. Who wouldn't. I'm still taking in all the info on dB this and that. Would an increase in 6 dB be that noticable? Just curious. I'll take some pics as I do the dirty deed if anyone cares to follow along. Thanks guys Also, any recommendations on thickness of material to line it with? Bill Quote Link to comment Share on other sites More sharing options...
DrWho Posted February 2, 2006 Share Posted February 2, 2006 Think of the 6dB as a 6dB reduction in distortion. And then also consider the added benefit of having a balanced bass image (technically it's not "stereo bass" but it's a lot closer). We never got into the nonlinearities of the active driver either...the less excursion the better (as the VC stays in the linear BL region and the VC isn't overheating, etc etc...). For a single driver to play 6dB louder, it would have to move 4x further! Btw, I would definetly double up the active driver baffle. What you can do is cut the front panel too large for the driver so that it slides right through and then mount the sub to the rear panel...it provides for a nice "flush mount". If you really wanted to be hardcore you would install a gasketing material between the basket and the wood as well (which with this kind of mounting results in a much better seal). Quote Link to comment Share on other sites More sharing options...
DrWho Posted February 2, 2006 Share Posted February 2, 2006 Btw, I was way off on those dimensions... One option would be 30" face width, 3" cut on the corners, making it 32" tall. (so it will stick about 26" out from the corner at a 45 degree angle to the middle of the front panel). Or you could make the enclosure taller too: 24" face width comes to a 51" height (4.2 feet). This would leave more than enough room for mounting the panel up above the drivers on one of the sides facing the walls. So in these situations you are going to want to employ a lot more bracing across the adajacent panelling. You'll have to choose a compromise between floor space used up and height of the enclosure, Drop me a PM with your email address if you'd like the excel spreadsheet. Quote Link to comment Share on other sites More sharing options...
billyjoe72 Posted February 2, 2006 Author Share Posted February 2, 2006 51" would be a pretty piece of furniture. I gave you a PM DrWho. This is going to be a big boy. Me like. I feel like a kid in a candy shop. Bill One more thing. With the taller one, does it need a 3" cut on all corners too? Quote Link to comment Share on other sites More sharing options...
DrWho Posted February 2, 2006 Share Posted February 2, 2006 Well the dimensions I gave you, yes...You can just set the corner cut to 0 if you don't want to have one. Btw, keep in mind that this is calculating the INternal dimenions of the cabinet. I would recommend having some form of "corner cut" for bracing purposes. You can do whatever you want to the outside shape of the box. Quote Link to comment Share on other sites More sharing options...
billyjoe72 Posted February 3, 2006 Author Share Posted February 3, 2006 Thanks for the email DrWho. I am going to use the taller one. I will cut the corners 3 inches. I think I will be able to squeeze in the amp with that height. I should have 9 inches or so to play with if I put it on a side with a PR. My mains are black klf20's so I'm going to stick a piano black finish on it. On paper what numbers do you feel this design with the arsenal and the PR's you showed will produce and compare to? Just curious. I'm still trying to figure that program out. It's a little overwelming.[] That way if I punch in my numbers, I can compare them to what you quote. I see there are a couple other people you are helping that are going to DIY. Looking forward to hearing about those results as well. Thanks Bill Quote Link to comment Share on other sites More sharing options...
billyjoe72 Posted February 3, 2006 Author Share Posted February 3, 2006 Jay and DrWho...I was wondering if you knew the specs on the drivers for the klf10 woofers. As said before, I built a center out of a scrapped klf10. It's loud but not alot of bottom end. I know the center is not needing bass. I was just curious. I'm more than sure its ported wrong. I'm not home right now, so I don't know the dimensions of the enclosure. Bill Quote Link to comment Share on other sites More sharing options...
DrWho Posted February 3, 2006 Share Posted February 3, 2006 I would just backwards engineer the KLF10 woofers using the internal volume and port diameter/length used in the actual KLF10. I'm at school right now, but you are looking at 112dB maxSPL with an F3 around 20Hz...excursion limited (both the actives and passives) to about 400watts. Don't forget to model the amplifier response (order 3 @ 18Hz). One other option you might consider would be the Dayton Titanic 15" woofer...same F3 and cabinet but I think 116dB max SPL? I forget. The titanics are on sale now and would cost you less than the arsenal. However, you would have to upgrade to a pair of the 18" woofers (which run $135 each). Btw, did you get my updated spreadsheet? I made the calculated dimensions a bit more clear. Quote Link to comment Share on other sites More sharing options...
billyjoe72 Posted February 3, 2006 Author Share Posted February 3, 2006 Yes, I received your email. Thanks again. I will try to find the specs somewhere for the ports on the center. I never had the klf10 enclosure. Just the drivers and crossover. Bill Get back to your school work!!!!!!!![] Quote Link to comment Share on other sites More sharing options...
billyjoe72 Posted February 3, 2006 Author Share Posted February 3, 2006 The dayton titanic is $175 and the two pr's are $300. It would be an extra $150-160 to go this route. 1. Will it be musical too? 2. I don't mind paying extra if the end result is fairly noticable. 3. If I took the enclosure 3 or 4 more inches higher to fit in the amp, will it hurt it? I'm going with your 28" sides and 36.9" height. 4. Will the impact crush my TV screen[] Quote Link to comment Share on other sites More sharing options...
DrWho Posted February 3, 2006 Share Posted February 3, 2006 I think the arsenal is much better bang for the buck. You're only gaining 1dB @ 20Hz with the titanic - and that requires EQ (using the parametric on the sub amp). I really don't think 1dB is worth $150... As far as the height of the enclosure...I would really try to stick with 7 cubic feet - the entire system just behaves better. If anything, you want to favor on the small side actually. The PR's are only 15" tall and the sub amp is 12".....so giving yourself some room you only need about 32" of height. A 26" floor width would yield a 43" height. Or a 28" floor width would yield 36" - so you've got plenty of room. Quote Link to comment Share on other sites More sharing options...
billyjoe72 Posted February 4, 2006 Author Share Posted February 4, 2006 I started cutting last night. Quote Link to comment Share on other sites More sharing options...
Jay481985 Posted February 4, 2006 Share Posted February 4, 2006 lol Homer Simpson would say D'OH! Quote Link to comment Share on other sites More sharing options...
billyjoe72 Posted February 4, 2006 Author Share Posted February 4, 2006 I have to get another sheet of MDF. I have 3 different technics of black piano finishes I'm trying right now. Best one wins..[] Quote Link to comment Share on other sites More sharing options...
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