Oh, I rekon Mega wants to compete in Street A. So I guess we can scrap my big idea.
As for the painting, I'll give ya $32.65 to take it off my hands.

 

Ok, I've got a question for my box.

On the inside of my box I have 3" strips in each corner (with 45' angle cuts on one side) So there wouldnt be any dead areas and the air would smoothly flow to the back of the box and out the port.

My question is: Is 3" enough surface area or would I need more like 5"?

 

bigger seems to work better from my experience...as long as you retain enough air space for proper tuning

 

I'm in the process of building/installing a couple rockford power Hx2 in a buddies truck. I was looking for a good way to shape the corners and edges inside the box and I found this landscaping plastic. (you use it to shape your garden or flower beds and whatnot. It keeps weeds and grass from growing into unwanted places). I cut the top and the bottom off it and its very pliable. I stapled it in place and fiberglassed over it. It worked like a dream...

I just figured yal'd like to hear a new way of doing it if you haven't allready tried it. I can set up a couple pics to show but I can't take em till tomarrow... peace out guys/girls

 

First off. I'd make a baffle piece that fit perfectly to the car first then build the box behind it sort of thing.

Sealing that truck off will be very important.

This first picture on this page is a sliding t bevel.

http://www.thisoldhouse.com/toh/prin...403568,00.html

You use it to transfer angles to other work pieces. It is also very useful with a speed square.

You can set the t bevel to a piticular angle using the speed square.

X

 

Test. But I think 3" will be enough.

When testing this do not glue it, so that you can easily test other pieces.

X

 

Thanx for the tips!

Using 3/4" MDF, what size of screws do you use?
• Length & #
• What size drill bit for the pilot hole?

[ January 22, 2005, 09:12 PM: Message edited by: 13idnyk ]

 

I use #8 floor screws, that are 1 1/4 long.

Buy a #8 pilot with countersnking head on it.

It's 11/64's BTW

http://doityourself.com/store/6089627.htm

X

[ January 22, 2005, 10:03 PM: Message edited by: Xiph0id ]

 

Alright send me the 32.65$ and I'll take it.

X

 

Alright I have been really busy at the shop lately so i have not seen this post for a while and now there are many questions so i will do my best to address as many as possible. Okay Jordy, the Fusion FJL1211D amps are not to bad but they are very inefficent, if they are modded the way that we modded ours they will run alot lower than 2 ohm, I daily drove one at 0.7 for like a month. Anyways here is what we found with them, we tested ours at 0.75 ohm at 17.3 volts, now it has been almost 2 years since we had them but if I remember correctly we got 93 volts A/C. That is not bad but you also have to take efficency into account before you can figure out appx. wattage. I cant remember exactly what the efficency was but it was down at like 50 and change if not lower, and at any higher impedance they got better but did not make the power. If I remember correctly at 1.5 ohm a visonik V900 smashed it by like 300 watts. All the testing was done by myself and Paul using Chris Cecco's Fluke multi meter and fluke clamp meter so the numbers were accurate. We used the Multi for all of the testing because of big battery bank, so all the amps had no chance to starve for power and only one amp was on at a time. The woofer we used was an 18" Treo CSX dual 1.5 so it was a reactive load. Now I dont know what the impedance rise was during that test but with the same model woofers later that season the impedance rise was very minimal. (And by the way the Treo CSX is the loudest woofer that we have ever tested [img]graemlins/bow.gif[/img] , 158.5 db with 2 18" and 2 Visonik V4000xd's running at 0.7 ohm not two on each 1 on each woofer and for the people that dont know the multi it was an SS 1-2 so a non modified front cabin) The h/u was a crappy like pioneer DEH 1500 so it had very little pre out voltage, this also proved to be a problem because these amps also want a hell of a lot of input voltage. We had to turn the line driver (which was an RW Audio line driver) to something like four and a half volts to get the most out of the amp, were most amps we tested only wanted between 1.8 to 3.5 *unclipped* volts at max. What that means is to run these amps to there full potential you have no choice but to use a line driver, even a high pre-out voltage deck like Alpine 4 volts, Kenwood 5 volt and so on wont cut it. I have put the Kenwoods, Pannasonics, Alpines, and Pioneers that have 4 volt and up pre-outs on an oscilloscope and all of the decks did output what they claimed or some were even more, but when they hit that mark the signal was so dirty it was useless. The Alpine came the closest to putting out the 4 volts it claimed before it started clipping and still not even within 0.5 volts of the 4. The Alpine started clipping at volume 27 and still had usable output at 29 and had 3.1 volts out at that volume 29. Anyways these are the findings that we came up with but if it were me I would get something else. Oh yeah and when those amps drop below like 9.5 volts they go into protect, so not a good idea for street. If you are set on using them fire me either a PM or an email with what was done to mod the amps, who did it, and who told that person to mod them that way. I have a diagram somewhere from the tech that actually designed that amp on how to mod it properly it is not just cutting protect but you need to actually use some diodes and resistors to mod them for for low impedance and what not. Wow this got long in a hurry. I will touch on one more then I will come back later and keep going. The rounding of corners in boxes for street does work but be careful.( and I specify srteet because we tried it in super street and was a nightmare) You have to makesure that the material you use is first off solid and not plyable at all, any thing that moves inside an enclosure is wasting energy. Someone said they were using something that was bendable, if it is bendable the density probably is not there. Also you need to makesure that the 45's are sealed right to the corners so there is no way that air can get behind it and it cannot be able to vibrate at all so I suggest not using sillicone to secure it to the enclosure just glue the hell out of it and then resin over the 45 and the rest of the box. If you will be using aeroports and depending on the shape of the box if you can load the woofer over top of the port so that the entrance point to the port from inside is as far away from the sub as possible do it, but keep in mind it may not work for all applications. Another thing that we found that worked was to take a board and make an angle almost like a ramp inside the box from the front bottom edge to the back wall of the box, and seal it to the box really really good. The degree of the angle will change due to things like port length, woofer mounting depth, and so on and really is not important. If you do this you will be taking up quite a bit of volume so plan this before building your enclosure so that you have the right air volume when you are done. As for the space that is underneath the board, you will need to fill it with something like sand, or dare I say it concrete [img]graemlins/thumb.gif[/img] pretty much anything that will get rid of that hollow sound you get when you hit the board will do. We found out the hard way thatif you leave it hollow underneath or fill it with something that has little density you just did all of that work for nothing so dont be lazy. I dont know how well I explained that so if anyone doesnt get it just let me know and I will try to get a pic of what I mean. I also want to stress that everything that I said is not a fact!! They are findings that we have come across and could not work for you so test for your self. Wow there were a few more things that I wanted to touch on but the Simpsons are on now and it is a new one so that will have to wait till after. Sorry for the rant and I will try to get on here a little more often so I can avoid long posts and buying new keyboards all of the time!!

[ January 23, 2005, 08:24 PM: Message edited by: orion ]