Outer Limits 4x4 Board

Was looking at a pair of 'free air' speakers today at a pawnbrokers.

They were 8" single cone and 100W RMS I thought hmmm, noooice!

But whats the free air thing about?

That probably means they're designed to not need a proper sealed enclosure (ie wooden box)- so they're suitable for mounting in parcel shelves, door cavities etc.

murcod wrote:That probably means they're designed to not need a proper sealed enclosure (ie wooden box)- so they're suitable for mounting in parcel shelves, door cavities etc.

Precisely!

Although I'm not sure of the implications of putting them in a sealed enclosure...

Scott

generally when it says open air it means yes they can be ran without a proper speaker enclosure, but this is due to the fact they are tuned with less effect from their surroundings, so they still can be ran in a sealed enclosure fine.
An open air speaker for this reason is very difficult to ever get to sound as good as one requiring an enclosure, if the other is in a proper enclosure that is.

Yeah, free air means that they dont require a specific style of acoustic suspension ( sealed / ported / bandpass etc.) as they have stiffer spiders in the build and different cone build etc etc. BUT they still require the most basic of all speaker principles - total separation of the front and rear pressure waves (remember a speaker is just an air pump) and subs in particular need to build a good pressure wave to be effective.

Free air subs can sound quite good in a sedan with the back of the seat and parcel shelf enclosed, including around any rear speakers, but its usually more work than it deserves.

for a cab chassis ute the best options are using subs mounted in an infinite baffle arrangement venting to the exterior of the cab through aperiodic membranes and gortex.

OR and i reccommend this highly, using 1 or 2 of the kicker solo baric square subs in sealed boxes, they require incredibly small boxes to work well, i think the 10 inch from memory only needs a 0.33 cubic feet box !!

whereas to build the 8 inch cheapies into boxes they would need about 1 cubic foot each to sound ok.

i agree with bradley, i had 2 10in solarbaric 500wrms subs in my ss ute and they really hammered. as far as install was concerned i made a box that fitted tight in the tray behind the seats and cut out the square shape of the subs in the panel pehind the seats. the box was fully sealed and painted in fibreglass resin to waterproof it. it never leaked of moved and was complete over kill for a 2 seater car.........just the way i like it.

free airs are a compormise speaker by all accounts and you will be rewarded far better if you can install a sealed or ported enclosure in your vehicle. this doesnt mean spending big bucks on a quality sub as a good enclosure with a cheap speaker will sound better that a top end sub in a poorly designed enclosure.

generally a sealed enclosure will give you real tight fat bass and ported enclosures have a better low end frequency range for that deep rumbling sound but require more planning in its construction.

regards,

nathan

I must be getting old, i thought a "Fat Bass" was a good eating fish, a "Ported Enclosure" was for engine performance and that "Deep Rumbling sound" came out of the exhaust!

heheheheheheh........Pete!

Gruntahunta wrote:I must be getting old, i thought a "Fat Bass" was a good eating fish, a "Ported Enclosure" was for engine performance and that "Deep Rumbling sound" came out of the exhaust!

heheheheheheh........Pete!

No, dummy....a "Ported enclosure" is a pub, and that "Deep rumbling sound" is a beer fart....