sub enclosure design help, from india

[sudhir kumar]

Hi friends,
I want some help regarding subwoofer enclosure design. I have listened many type of subwoofers with different enclosures but with the following type,(image attached, perhaps fourth order) of enclosure, I felt the best bass response(according to my taste).I have this subwoofer but with very little power & little subwoofer (i.e. 18 watts rms with 100mm sub ),now I want to make it in a big configuration, like with 12 ,15 or even 18 inch sub with 200-500watt rms power.I know that there are many software’s available on net for speaker designing but my problem is that in my place I cannot buy any specific brand sub speaker with specific parameter(due to absolute non availability of branded speakers). I am totally dependent upon local made speakers. Here a lot of shops/manufacturers make sub speakers but for them parameters means size of cone, size of magnet, type of cone(fibre or paper) and handling power(that too approx ) and with these data I cannot design a enclosure.
Friends , I want to know that is it possible to make a sub enclosures mentioned above with available data ? of course the most true data from my manufacturer is its size and nothing.
Kindly give your valuable comments since I want to make a really big & powerful sub. Friends from India are kindly invited because they are familiar with these conditions.

Thanks.

[sudhir kumar]

anybody please reply..........

[AllenB]

Everything you need can be measured. You want to start with Vas, Qts, and fs. You can even guess Qt when you are purchasing by looking at the size of the magnet.

[ravslanka]

Originally Posted by sudhir kumar

anybody please reply..........

hi sudhir,

first select a driver and buy it.measure its ts parameters.most of the drivers
have very high qts, qes vas and very low ebp .i have tested many of them locally available in lajpat rai market delhi.most of them acquire qt,qe of ranging
from 0.90 to 1.2.i made my own drivers from locally available parts
but story remains the same.


but you will be astonished when you measure ts parameters of drivers
coming out of those sony,philip,screative and so.......
they have similar ts parameter high qt,qe,fs low ebp still they manage to produce so called bass.

it would be better first you measure frequency response of of your
4th order bandpass.then buy a driver measure ts parameter
put them in winisd better in bass box pro.and tune it closely to measured
response.

i managed to make a 18inchi driver for horn with low qt,qe high bl low fs and vas withhelp of a software .but now i ran out of money to further experiment.so everything is stopped.only the raw material costed me around3500 rs.

one of 4th order band pass drivers ts parameter attached .

regards

ravs

be a vegeterian.....

[doors666]

you can try to get it from US. if you know people in software, someone or other keeps travelling. I got my css sdx15 thru a friend who was kind enough to get the 45 lbs monster for me

You can also try hifivision.com, thats india specific av forums. you will find a lot of people from bangalore there that might be able to help you.

you can also use shipping services to get it from US to india. e.g. 20north, aramex, borderlinx etc. though shipping charges might be hefty.

[sudhir kumar]

Originally Posted by AllenB

Everything you need can be measured. You want to start with Vas, Qts, and fs. You can even guess Qt when you are purchasing by looking at the size of the magnet.

thanks for suggestions,
I have very little knowledge about speaker parameter and enclosure design.I have started learning from esp site.

[sudhir kumar]

Originally Posted by ravslanka

hi sudhir,

first select a driver and buy it.measure its ts parameters.most of the drivers
have very high qts, qes vas and very low ebp .i have tested many of them locally available in lajpat rai market delhi.most of them acquire qt,qe of ranging
from 0.90 to 1.2.i made my own drivers from locally available parts
but story remains the same.


but you will be astonished when you measure ts parameters of drivers
coming out of those sony,philip,screative and so.......
they have similar ts parameter high qt,qe,fs low ebp still they manage to produce so called bass.

it would be better first you measure frequency response of of your
4th order bandpass.then buy a driver measure ts parameter
put them in winisd better in bass box pro.and tune it closely to measured
response.

i managed to make a 18inchi driver for horn with low qt,qe high bl low fs and vas withhelp of a software .but now i ran out of money to further experiment.so everything is stopped.only the raw material costed me around3500 rs.

one of 4th order band pass drivers ts parameter attached .

regards

ravs

be a vegeterian.....

I already have two 12inch driver & i will start learning from these.I will try to mesure its parameters.It seems that making a good sub enlclosure is not a easy task.Is it not possbile to get a universal mesaurement for a specific type of enclosure with a known size of sub driver /

[sudhir kumar]

Originally Posted by doors666

you can try to get it from US. if you know people in software, someone or other keeps travelling. I got my css sdx15 thru a friend who was kind enough to get the 45 lbs monster for me

You can also try hifivision.com, thats india specific av forums. you will find a lot of people from bangalore there that might be able to help you.

you can also use shipping services to get it from US to india. e.g. 20north, aramex, borderlinx etc. though shipping charges might be hefty.

I don't have such contacts & i think when importing from other countries sometimes the shipping charges itself are more than the cost of item.

[AllenB]

If I were you, I'd try to measure those three things, and then consider a closed box of the right size. Often a subwoofer enclosure is made in the shape of a cube.

[sudhir kumar]

Originally Posted by AllenB

If I were you, I'd try to measure those three things, and then consider a closed box of the right size. Often a subwoofer enclosure is made in the shape of a cube.

Which three things ? I have a closed box dimensions from rod's site but due to poor efficiency i don't like closed box.