old dude

Ok but this test is not anything but a test of a whole system instead of an amp with a dummy load on a test bench. It’s nice to see people posting test numbers. What would be nice to see is all of the big amps tested at the same place by the same person on the same bench with the same load and same power supply. That would be a test to end all arguments to me. I am always interested amps pulled vs watts produced and that is an important factor that gets overlooked on most test anyways.

Hey Rusty I love my level 5 18s and I would like to use some DC subs in my new home theater room. Have you got anything you can fix me up with? Two 15s or 18s isobaric/ infinite baffle style. About the only thing on the market right now in this category that I see is the Dayton IB385. It would be way cool to have DC in my house Rusty.

Correct, it was allegedly for an RE xxx 12" @ 15" in height. I have no idea about tuning because this is nothing like a regular ported box; it is, from what I understand, something to do with 1/4 wave(which im not sure how that is build to the woofer itself, as I understood it as being install dependant). 1/4 wave was a huge thing and surely still is in the SPL world, and less used in the daily world, but several VERY loud people still use it/build around it, damn over-achievers. Just a short version of it. ^^ True enough getting the quarter wave figured so that you can pound that meter on the windshield is worth every minute spent when competing. Sometimes just moving the box an inch or two will change the wave enough to get a 2db increase. A 2db gain that came from alignment mind you not power that’s how important the quarter wave is in competition.

That’s amazing I didn’t think DC subs could be damaged.

How much power are u running to them The last test I did showed 2520.5 watts each averaged. That’s with 1.63 ohms of rise. Two vfl 500.1s 1ohm each. I will be strapping the two amps @ ¼ ohm in the near future to get some real power. I need 6 db to get me where I want to be in ssnw for this year. I still have some more stuff to test with the box and my quarter wave but I think 160s are coming soon.

154 today on two level 5 18s @ ¼ power so I know she has them 160s still to come.

i can burp a 158.5db at 40hz and play music at mid 157s all at 40hz pretty cool for sure

Music is dynamic so what power I am sending to the subs while playing music will be ever changing never a constant amount. That being said first my level 5s could see 4200wrms each on music that had long notes @45hz in a daily setup.

Subs really should not get hot in any kind of box. If they are getting hot you have something set wrong or you have way to much power going to them but it is usually the first one.http://www.stevemeadedesigns.com/board/public/style_extra/post_icons/icon1.gif

have some fun and enjoy yourself.

I should be good by then I need to get with some one that has a term lab to do the testing. Someone up in Cleveland has offered to help but Columbus would be a lot closer. If you know anyone that I should call let me know. I have built a meca kids car that I would like to show off too.

Thanks rusty what would really help with those numbers is to have you in my garage helping out but I sure do appreciate any input from you. I have 228 sq in of port for a starting point and a couple of saws. We are going to put it on the term lab this weekend and start playing with port size and box volume.

two vfl 500.1s @1/2 ohm for now

18" level 5s

The back and the front have gaskets so they can be removed to make changes. Testing on the term lab will begin this weekend if all goes well. There is still a lot to get done I think I may have damaged one of my alternators while tearing everything out. Did you notice the nice window art that Rob gave me at world finals.

still have a long way to go before testing starts. Tomorrow is another day maybe i will get to hear it.

I have been asking around about the science behind that idea of keeping them close together. I don’t doubt that they should be closer together but it would be nice to know why. How is the air movement off the back side of the subs better or worse by placement?

full size 92 ford van

i think your right i dont know what i was thinking but i am going to give it a try before i make a new front panel who knows maybe it was devine intervention.

ha ha no it is 67" here are some pics That’s where the front panel goes with a gasket so that I can test and remove it if I want to change before I glue permanently. front panels over 4" thick when put together and flared on inside edge.

I am building a new box 4” thick and I have cut the holes in for my two level 5 18s After I cut the holes for the subs I looked at it and wondered why I spaced them apart so much. Then I sat down started thinking maybe they should be closer together but I don’t remember ever seeing any science on spacing. I know its all about the testing and rebuilding and more testing. This is the box I am building for ssnw it is 67” wide and 26” tall with a 12”wide port 18”tall that left me 10” to play with on how far apart to place the subs. it is bothering me that I spaced them so far apart but I don’t really know if that’s a bad thing or not. I guess testing will tell but if anyone has a clue what I am talking about chime in please.

good point. i need to look at that i thought it was no mods in front of B pillar. as far as i know it's nothing in front of the b pillar or above the window line. nope no body mods period in no wall no cutting metal or adding you can't take everything out behind the b pillarmake a batt rack thats not welded to the body and so on ive had my hand in a few no wall builds every no wall champ i know used 18's your right no mods i looked at the rules again thanks.

it was 45 with out the wall and then 44 with the wall. i had read that you tune the box lower than the resonant frequency of the vehicle instead of at the frequency.

good point. i need to look at that i thought it was no mods in front of B pillar.

I just gutted everything in my van and i am ready to start a new box for super street no wall. 2 level 5 18s on 2 vfl 500.1s and 2 ho alts with plenty of batteries. material for new box is sheets of 1 1/2" thick mdf front of box will be 4 1/2" thick. top and bottom sides will have to be 3" thick in order to keep 18" subs below the window line which in my van is 26" i am starting the box at 19CF and will reduce down by adding to the rear wall until I hit the peak on the term lab. so this is going to be my first time in no wall. I dont think I have room for a cage or do I? With my front wall being 4 1/2" thick I already have decent depth for a tune in the forties. a question on that is if my van peaks at 45hz then do i build the box to around 39hz?