passive radiator

Post by **bdubs767** » Thu Dec 07, 2006 9:07 pm

any one done a install w/ one? Hows it sound? Delayed response from the passive?

JW as Tom and I have been chatting about this for a few days, and since I never heard one JW what its like.

Post by **bdubs767** » Thu Dec 07, 2006 9:16 pm

some one else gotta post a new topic, your killign me here making me look like king Newbie lol.

Post by **VW337** » Thu Dec 07, 2006 9:31 pm

A passive radiator is a nice blend between ported and sealed.

It will allow you to play more efficiently similar to a ported enclosure while maintaining a smaller enclosure by comparison. They can make response a little muddy, but if tuned right do quit well in bumping the desired frequency without damaging accuracy.

They are a bit touchy and I would suggest having an RTA handy while tuning as there is a science to it but it is not exactly perfect.

Two of my 3 loudest vehicles used them.

brenzbmr@sb · Post by **brenzbmr@sb** » Fri Dec 08, 2006 12:10 am

where can i buy passive radiators, thinking of doing one.

Post by **bdubs767** » Fri Dec 08, 2006 7:27 am

brenzbmr@sb wrote:where can i buy passive radiators, thinking of doing one.

http://www.madisound.com/cgi-bin/index. ... 45124.2751

thats peerless they also have a woofer they recommend to be used with it in there.

Boston acoustics also makes a passive radiator too.

http://www.bostonacoustics.com/car/car_ ... ily_id=108

Post by **VW337** » Fri Dec 08, 2006 9:01 am

brenzbmr@sb wrote:where can i buy passive radiators, thinking of doing one.

You can make your own. Take an old deceases driver to which you have a functional mate to. Take out air saw and cut the motor off just below the spider. Now gently remove the voice coil assembly just below the spider. Make a plug to seal the hole in the former where the former meets the spider (thin mdf or abs will work). Epoxy a 1 inch #6 or #8 bolt to the plug then epoxy the plug into the hole in the cone.

Now you will want to play a few test tones near the structure to find where it resonates at, add nuts to the bolt on the plug to lower the resonance. If you need the radiator to be shallower you can completely remove the former and spider but you'll need more weight on the bolt and it will tend to be a bit sloppier.

Post by **bdubs767** » Fri Dec 08, 2006 9:20 am

Errin any chance you could find a destroyed RSd around that is making its way to the trash? I woudlnt mind playing with this.

Post by **VW337** » Fri Dec 08, 2006 10:55 am

bdubs767 wrote:Errin any chance you could find a destroyed RSd around that is making its way to the trash? I woudlnt mind playing with this.

You don't need an RSd as any sub will work, but cosmetically if you use the same driver it looks better.

Post by **Bfowler** » Fri Dec 08, 2006 12:01 pm

so what if you had a sub.....purly for examplie, one that played around 90hz, but ws pretty damn efficant and big and was a PG rsdc, would a passive radiotor help make it even louder....in say a 81 honda wagon with say....a pair of xenon 600.1s?

HoseHead · Post by **HoseHead** » Tue Dec 12, 2006 6:23 am

I run EPI Model 500 towers in my home AV system. They were built in 1979 and have a 12" passive radiators in each side of the side cabinet. Active components are 10" sub, 6" mids and 2.5" tweets. I need to push large current through them to make the passive radiators come alive, but when they do, the sound is outstanding.

The person I bought them from used a Phase Linear 1200 amp, back when Phase Linear devices were hand built and designed by Bob Carver. Raw power. We got liquored up one night and couldn't roast these speakers.

As far as passive rads in a car.... I've not heard. I suggest, if driven properly, they would work quite nicely. But then again, my take on pasive radiators is to enhance the low end in a large room. A car is not such.

I'll throw up some pix later today.

HH