Car subs for home theatre

[renjiish]

i think you haven't read my paper completely. may be you haven't got enough time. please check my references.

 

[richie00boy]

In that case, you better check your references For in Small's Vented box paper lies the answer to your question. The second page of the Vent Design part.

 

[renjiish]

can you please tell me which line it is. i used his method

 

[richie00boy]

Small's Vented Box JAES paper, second article. Para 8 Vent Requirements, page 330, equations 51 and 52 and the text surrounding them.

 

[renjiish]

i thin i am using different paper. i cannot see that paragraph. can you please copy that and paste it here, if possible.

 

[renjiish]

my page starts from 363

 

[renjiish]

i will be very happy, if you can send me that paper

 

[renjiish]

i found it. it is his second paper. i just downloaded. page number 441.

 

[richie00boy]

Maybe you have a different publishing, mine is the JAES one and is page 330. But if you found the information that's all that matters.

 

[renjiish]

Thank you very much for your help. Definitely I will include this one. You can see in my references that I have not mentioned about the second part that paper. This was really enlightening.

I was thinking that I have to change my design. My design meets that requirement. The required minimum diameter is 0.125 meters according to the formula given by Dr. Small and I had taken it as 0.13meters.

So I think I can stay with same design without any complication. Thank you once again for the improvement

Thanks and Regards
Renjish

 

[richie00boy]

I think you misunderstood, or maybe you are looking at the wrong bit, he doesn't give a minimum number. He says the minimum diameter is dependent on air speed which is dependent on tuning frequency and displacement.

The papers are all on my website. Maybe you should check there as it seems you might have the wrong one.

 

[renjiish]

ya i found that way only. i calculated first the volume displaced by the woofer 'Vd'and multiplied by 'fb' and took the square root of the value.i found it is 0.125.
and i took 0.13meters as my diameter vent.

this is my understanding

am i right

 

[richie00boy]

Yes that is the right value for the minimum. But that value is only applicable to that one particular case, if you change the driver or the tuning frequency the value will change. I think you know that but it was not clear for others IMO when just a number is given.

 

[renjiish]

ya i understood it very clearly. iam attaching the calculation

 

[Vivek]

Hi guys, I don't mean any offence to anybody but has this thread not changed direction? Pleaseeeeeeeeee! I need to build a HT sub.

 

[renjiish]

sorry for that my dear friend.don't worry i will keep quiet. good luck for your subwoofer
adios

 

[aceinc]

Vivek,

So where are you in the design/development process for your sub?

Paul

 

[Vivek]

Paul,
I will most likely build two boxes of 60L each (including bracing etc). Effective volume will be around 50L. Then LT them. I think that is the best approach now.

 

[navin]

Paul,
I will most likely build two boxes of 60L each (including bracing etc). Effective volume will be around 50L. Then LT them. I think that is the best approach now.

If you tune it to 30hz you should be ok. Any lower and power demands will go up as well and i know you are having a had enough time finding a suitable amp. You should use 2 amps (one for each woofer).

 

[Vivek]

So shall I go ahead and build two 60L boxes? Since I am not really going to build a TL and all that, I think 60L boxes will do even in the event of me building vented boxes.

If I can get it down to 30Hz, that will be pretty good I think. Maybe a slightly higher F3 will also be okay.