passiive radiators...

[bmccord]

I had a quick question. I finally figured out what I am going to do for my next DIY sub project. Aiding in cost reduction, I am using a couple of subs I forgot were in the basement. I have 2 Audiobahn AW1000 10" subwoofers that are about 4-5 years old now and have not been used in several years. They have an Xmax of around 23mm and F3 is 23 Hz. However, they are pretty uggly and will be down firing because of that. Now here is my question. I was thinking of adding a 15" passive radiator to the front of the box. Do you think this would be a good idea. I modeled the 2 subs in WinISD and the box will be almost 6 ft^3 with 2 25" long 4" ports. I figure I could have the 2 10's down fire and have a 15" radiator at the front of the box. Do you think a 15" PR would be big enough or would I need 2 12" units. The subs are 600w RMS and are dual voice coil 4 ohm so I will be using the Dayton 1000w plate amp. Thanks in advance. I will post all the specs for the 10's later tonight and I was looking at the dayton DVC series PE's.

 

[bmccord]

Ok, I have done a little more research. I still have to do the math but one 15" PR will not be big enough for 2 high excursion 10's. I think it will end up being either 2 12" PR's or if need be 2 15" PR's. I like the idea of making a cube, with a 10" driver on the bottom and front, PR's on either side and the amp on the back. So basically if I use 12" PR's, it would be around a 16-18" cube and if 15's, it would be a 19-20" cube with something stuffed in every pannel other than the top...

 

[rlammi]

passive radiator

From what i have read the pr is basically acting like a port .
I have a 12 in sub with matching pr in a sealed box .I would think if you are going to ad a port just make it with the two ten inch drivers .mine sealed is on 2.4 cubic feet .
I am not totaly up on all the particulars with a pr, so if some one has more info please chime in ,also pr's at least mine ,I can add weight to it for more or less movement in the drive .

 

[bmccord]

From what it looks like with the excursion and Vas of these subs, they move a pretty good volume. I figure going with one size bigger will do the trick and seems to be the norm. From what I have been seeing, you get almost as good of a responce as a port, HOWEVER, with these subs having a bit higher tune (meant for a car), the box ends up being near 7.5 ft^3 and a couple 26" long 4" ports to get a tune of around 22-23 Hz. It seems as though I can acheive close to the same tune by using about 1/3 the volume by adding a couple PR's. There is also something intriguing about a small cube with 4 "drivers" and an amp stuffed in it. I figure I will use the 1000w amp for this and then in the future use it for my much larger sub project, but I could toss in 100 bucks or so in PR's and maybe make something pretty interesting.

Brett

 

[rlammi]

check out this site

Hey bmccord here is a site with alot of subwoofer info may or may not help .good luck with the sub .I have built one with a passive radiator ,but now I am going to build and
I/B sub .hope the info helps.
http://home.comcast.net/~thomasw-2/SubwooferSetupandEQpage1.html