Passive radiator

[Ben Lawrence]

I have a sub with a couple 12s in my van. It seems like when I have some other subs loaded right up next to it I am getting more bass content from the system. Is this possible? Or just in my head? The subs would be passive double18s or single 18s. They are passive but of course not actual passive radiator cabs.

 

[Timo Ulkuniemi]

Hello

An unterminated speaker acts as passive radiator - many speaker design programs allow you to use speakera as passive radiators. Fs becomes Fp etc. While they are not in same box with active speakers makes situation more tricky and is comparable to any other resonances there might be.

Obviously your gasmileage will improve ...

 

[Ben Lawrence]

So frequency response will be affected. Guessing its not possible for the db to see a gain with the same power? Going to have take a few db readings.

 

[Rob Timmerman]

It's possible to increase output at some frequencies at the expense of lower output at other frequencies (constructive/destructive interference). Total energy is conserved, of course.

 

[Helge A. Bentsen]

In my Suburban the sub response changes when I put a lot of stuff in the rear. Seems like it's more about affecting the total air volume than what I put in there, to my ear it sounds similar if it's a pair of flight cases or a pair of subs.

BTW: A Kicker Solobaric 15" in a sealed box is a pretty decent sub for a car, sounds smooth.

 

[Tim McCulloch]

Passive radiators are a form of porting, like a bass reflex design.