For those with experience in audio, how important is it for a sub to have a low Free Air Resonance in achieving good low frequency output? After looking at the specs for the 12w7 and the old school 12w6, the w6 has a Fs of 20hz whereas the w7 is 25hz. I had a 12w6 back in the day and that thing hit the low notes with ease.


Ideally, I'd like to run a 10w6v2 in my G35. With a Fs of 28.5hz, how can I get it to play low notes efficiently like a 12w6. Would I just use a bigger box and put in some polyfill? How much bigger would I have to go from the recommended box size? It doesn't have to play loud. Just have good output in the low frequencies.

 

The Fs is an important spec for the person that likes to go overboard. If we were to go off this spec the old version 1 w6 would be better then anything they currently make, but there are other more important stats to look at. All that the Fs is is the point at which the speaker creates its own frequency. It is important to note on a highend system this parameter as you'd want to tune the box to not allow the sub to get out of control at said frequency. As for real world testing and listening. The w7 will play very low and loud. The w6v2 will play just as low, but with not as much force. It will also play faster as there is less moving weight allowing better transient response......ie; it sounds better. If you want the w6 to play lower, build a box a bit bigger, reinforce the inside so there is no flex of the walls, and drop some polyfill in.

 

i doubt the human ear can distinguish between 20 and 25 Hz anyhow...

 

The ear can't... but the liver can. Seriously, the liver is a secondary auditory organ.

Fs is important, but so is every other Thiel-Small parameter, and I'd like to simplify it for you, but I can't, cause it's not simple.

 

Yeah. We can't hear frequencies that low, but we can definitely feel it. I guess I'll just have to do some more research to satisfy my knowledge.

I guess there are calculators out there that will predict a subs frequency response given certain parameters?

 

There are programs hat will calculate it in a football field.

In a car, that's a different story.

Most of what people think is low bass is around 40-60. 25 Hz is whales mating, seismic activity, and pipe organs.

 

Enclosure design and execution is more important than free-air resonance.

 

But you can't get that right without KNOWING the free-air resonance. : )

 

This is true, but so is knowing the other T/S parameters. Although, most subwoofer manufacturers have completed this work and have recommended enclousre volumes available. Most people would consult either the manufacturer or a dealer and simply get the enclousre volume, without the need for any of the T/S parameters. You are absolutely correct though, anyone who wants to manipulate the formulae will need the Fs to ultimately come up with a starting point for a 'good' enclosure.

 

badtziscool, I would consult an authorized JL Audio dealer. Each dealer has a comprehensive subwoofer manual that will give you a range of enclosures to use based on your listening desires.

 

Why I said...

The JL manuals are designed to help you execute a competent enclosure without knowing what you're doing. This is the key to JL's success.

 

Typically the "recommended specs" for an enclosure is like reading a "for dummies" book. Its the 'safe' enclosure they recommend to avoid having people send back their blown subs.