Ported Problems....Hollow sound....

[Cameron_B 10+ year member]

I have a ported box 3.0~ at 32hz....2 RE SE and im get a "hollow" sound and loss of pressure at certain frequencies.

It's like its not got back pressure on the cone....almost like its free air....

I have the SSF set at around 30.... I thought it was bottoming out...

For instance on TI-top let back

the first line of notes

Dum da dum dum da da (hollow) dum (full sounding)

Click to read more...

 

[blackbonnie 5,000+ posts]

sounds like you ported to low. do you have specs on your box?

 

[Cameron_B 10+ year member]

3 cubes at 32hz slot port.

 

[streetbeater07 10+ year member]

I don't think there is any note in that song that goes below 40hz

 

[Cameron_B 10+ year member]

Maybe it's playing out of its range 100hz+......?

What I can tell you is that in my sealed enclosure for the same subs

it hit all notes in the song almost equally....

sealed it was around 1.3 each...

Another example is the "bumps" at the begining of the song it misses, but the bass line it slams.

Maybe its because im used to running sealed all this time, and am just not used to shallow "hits" and wide lines.

 

[bass-aholic 10+ year member]

Dum da dum dum da da (hollow) dum (full sounding)

lol

 

[x2o 10+ year member]

Your box may have a nasty/peaky response, or your LPF is set up high and it's playing mid notes, which will result it in sounding like shit //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

And honestly, I LOL'd at :

Dum da dum dum da da (hollow) dum (full sounding)

Sad part is I'm pretty sure I can understand how you mean it sounds, haha.

 

[PV Audio 5,000+ posts]

sounds like you ported to low. do you have specs on your box?

Ported too high would be a more logical solution. If you're peaking the system in the 40s, your rolloff will cause you to not have any damping on the back of the cone at lower frequencies.

 

[Cameron_B 10+ year member]

Alright Ive narrowed it down my taking a ride XD I am 75% sure I have the lpf set to high....these SE's must have horrible 75hz+response....they are monsters around 40hz though.

 

[cshaw 10+ year member]

oh geeze, subs playing at 75hz?

thats mid bass!

try turning down your lpf 20hz depending on how many db per octave your x/o is.

 

[PV Audio 5,000+ posts]

Actually, anything below 100hz is fair game for a subwoofer. That's when the sub-bass region starts.

 

[Cameron_B 10+ year member]

Just went back sealed....maybe not as loud but WAY cleaner.

Screw ported.