slim and tall 12" ported subwoofer - port location query

[audfrknaveen]

Hi All,

Due to some space constraints, I have to build a subwoofer nearly 30" tall.
Please see the attached image and suggest which location is better for the port.

Near to the driver? or Away from the driver? Does it have any effect on performance ???

Thanks in advance...

 

[RichK]

Suggestion: port and driver located close to boundary- floor.

 

[wonderfulaudio]

At the sub frequencies, makes no difference

 

[audfrknaveen]

Two different answers

I'm wondering port location has any positive or negative effect on bass. Is there anything like phase matching etc ???

 

[wonderfulaudio]

The port operates in about an octave at most. With a 30hz tune, the highest freq is 60hz, thats (345/60) 5.75m in wavelength. To get boundary loading, the source must be within 1/4 WL, which is about 1.43m from the floor. Assuming a sane height of the enclosure, its location does not matter.
More so, if the tuning is lower.

There is no difference in phase. Take the port location to extreme, on top-rear, even then its going to be in phase.

Room acoustics (phase and SPL) will overshadow everything else.

 

[bitSmasher]

Would cooling via airflow be a factor?

 

[audfrknaveen]

started building it ... see the pics