sub-woofer encloser size problem

[Audioguru]

A little woofer in a little box is NOT a sub-woofer.

 

[ALERTLINKS]

A little woofer in a little box is NOT a sub-woofer.

Yes, it should make your dress vibrate .

https://www.hometheaterforum.com/topic/243802-quad-tempest-classic-sealed-lt-sub-array/

 

[Audioguru]

The LT (Linkwitz Transform) circuit is a bass boost equalizer for a powerful speaker in a sealed enclosure that is too small.
It used a speaker with a very low resonance frequency in a sealed box then its -3dB response was 37.6Hz, and boosted the bass so that the total was pretty flat down to 20Hz. The boost at 20Hz was 8 times the normal amplifier power.

The little 6.5" woofer linked in the other thread will smoke and burn if it uses this circuit.

 

[swavvv]

i have another Woofer which is ok for real bass effect? **broken link removed**
and which size we need to construct enclosure

 

[Audioguru]

It looks like a pretty good woofer speaker.
Here in The West the speaker manufacturers recommend an enclosure and they show it on their datasheets.
But you can look in Google to find an enclosure design site where you enter the detailed spec's of the speaker and it shows a sealed or ported enclosure design complete with a frequency response plot.

 

[Kral]

swavvv,
swavvv,
To obtain optimum performance from a driver, the enclosure, whether sealed box or ported, must be carefully matched to the driver. To get optimum response from a driver, you need the following:
1 An enclosure design program. There are several free ones available, including "Woofer Box and Circuit Designer, available at http://audio.claub.net/software/jbabgy/Woofer Box and Circuit Designer 5.zip I have not used this program, but it has received good reviews. The program that I uses is "Bass Box Pro", but it is not free.
2 You need to obtain the Thiele-Small (TS) Parameters from the driver dealer or manufacturer. The TS parameters are a set of parameters that allow you to design an enclosure that will provide predictable results from a driver.
.
As an alternative to using box design software, you can design using a set of equations that use the TS parameters. The book "Speaker Building 201" by Ray Alden is a good book for beginners. It has step-by-step procedures for designing either sealed box or ported enclosures using the TS parameters without using speaker design software. Your chances of coming up with a decent design by guessing at enclosure dimensions are very slim.
.
I agree with betwixt's comment that 0.4mm is too thin.