Correct Port frequency for Vented Enclosure

[mengz]

Hi All,

would like to find out how do we determine what is the correct port frequency that we should have for our woofer. is it determine by the woofer's frequency response range?

for example, if my woofer has a frequency response of 30-3000 Hz. therefore my port frequency should be 30Hz?

thanks in advance.

 

[cacin]

Hi Bro,
Do you have the t/s parameters of your woofers?
Pluck them in winISD, from there you should be able to have the box size and port tuning frequency and the response of the sub with the box. You can try alter box and tuning frequency to get the response you need/want.
It even allows you to simulate the response from your sub if you have eq, e-x-over and such.

Hope this helps.

 

[mengz]

Hi bro,

Thanks for the info. will give winisd a try.

1 more question, when u say 'to get the response i need/want'. what do you mean by this?

 

[Zenn]

port tuned to what frequency u prefer, where u want the most bump to be at, also related to what music u want to play loudest.

usually for techno it will be around 70-80. from there u plot your sub and box details into the software to get the correct port size.

 

[mengz]

what if i want SPQL what would be the recommended frequency?

i do listen to some hard hitting bass music...but sometimes i listen to alternative, sometimes chinese pop songs...english pop songs......hehehe...so which frequency will be a good balance for this situation?

so for pure techno, the port frequency shud be around 70-80???

 

[cacin]

If you use winISD, I think you should be able to see the frequency response of you sub in a particular box design. With that, you can decide which particular frequency you want to 'bump'. then from there, you might get the suitable port design.

 

[Zenn]

theres no easy answer if u want to play ported properly, a lot of research and trial and error, thats why most of us just use normal sealed box to get the most uniform response. u can use extra large box if u want it to be louder and go lower...

 

[mengz]

hmmm......i guess ur right....i think i'll just go for a sealed box then.

 

[appleyard]

what if i want SPQL what would be the recommended frequency?

Thats a new term to me.

i do listen to some hard hitting bass music...but sometimes i listen to alternative, sometimes chinese pop songs...english pop songs......hehehe...so which frequency will be a good balance for this situation?

so for pure techno, the port frequency shud be around 70-80???

Porting at 70-80hz is a little bit too high. Not all bass is within the range of 70-100hz. You should try to port around 40-45hz instead. But 33-35hz is ideal tuning freq. It has the lows and highs but not as strong high as 45hz.

 

[Kippo]

mengz,
Zenn got it right. The port tuning that you should set it to will depend on the kind of music you listen.

Rock / asia-techno : use high port tuning freq. 40~50hz

Rap / Techno / pop : port around 35~40hz

hip-hop/trance: port around 28~35hz

If you like smooth response with small peaks then look into tuning a lot lower eg. 20~25hz. But you must have a good midbass.

Port tuning of 70~80hz is kind of way too high. I would not recommend it.

 

[mengz]

hehehe appleyard....."SPQL"....just an acronym for SQ + SPL :P i learn this from DjThormented.

thanks for all the info guys....really appreciate your time and help. i guess i'll play around.....trial and error :)

 

[Kippo]

mengz,
one thing i forgot to add, whatever the port tuning freq. of your sub, the car 'cabin gain' will affect the overall package. You may need to lower the port tuning to get the same extension in a smaller car.

 

[renxun]

as on my previous thread i mentioned that i did a 2.4 cu feet sealed enclosure for my 15" . and my electronic crossover i went deep down to 32hz and the bass is so sweet for my sentimental songs. however when i wan to blast i turn the knob until 60hz and seems the bass was not punching . not as loud as my friend's 2unit of 10" shuttle lab single coil. so i actually i was planning to do a 4" port and the length of 7inches but at that time i couldnt source for 4inch pvc pipe... so i just opt for the 3inches and 8" length instead. now its getting loud. but i need to wind up my crossover up to 90-100 hz in order to get the window cracking punch. Doing iasca musics was deadly however my SQ for d soft sentimental tight bass went down the drain.

so for the time being monday to friday i will just stuff the port with rags to let it be a sealed enclosure and vented on weekends for some down town blasting . i would like to get a balanced for my sentimental songs and SPL as well do i actually need the 4inches port with 7" length.? do enlight me on this

 

[Zenn]

should leave the crossover fixed and play with a sub eq, to boost the correct frequencies.