Possible to get this from ported sub?

[derekwwww]

Hi guys, another question for those experienced with different sub setups.... I am running 2 12" IDQ's sealed running off a 1000W PartsExpress plate amp running in 8 ohm so about 500 watts RMS or so to the pair. After only a week I am wishing I would have went ported. The bass in some rap songs will drop so low it pretty much disappears completely. But on the other hand, listening to my metallica CD, the subs play the drum bass very tight and accurate. And I'm thinking to myself, if I would have went ported, they would sound sloppy on these tight drum notes. Am I correct thinking this or is it possible to have a ported sub hit nice and low say 20-25 hz with good response for rap and also play nice tight drum bass for say metallica?

Thanks

 

[Bredick]

why not do bandpass? keeps tight control like sealed and low end output like ported, and quite tuneable.

 

[cbraver]

A sealed enclosure will go lower than the ported. So, it sounds like your box is poorly designed.

-Chad

 

[derekwwww]

Yes my boxes are probably too small at only 30 litres each box. So your saying a properly designed sealed will be louder at low frequences (20-30 hz) then a ported?

 

[Francious70]

Yes. Power handling and cone excursion go to the wayside below the tuning frequency of the port, which mean you need to run a HPF or Subsonic Filter at the port tuning frequency. (Port tuning frequency for a 12" driver is usually in the 30 Hz range.) So you loose almost all sound below that frequency.

Paul

 

[WmAx]

Hi guys, another question for those experienced with different sub setups.... I am running 2 12" IDQ's sealed running off a 1000W PartsExpress plate amp running in 8 ohm so about 500 watts RMS or so to the pair. After only a week I am wishing I would have went ported. The bass in some rap songs will drop so low it pretty much disappears completely. But on the other hand, listening to my metallica CD, the subs play the drum bass very tight and accurate. And I'm thinking to myself, if I would have went ported, they would sound sloppy on these tight drum notes. Am I correct thinking this or is it possible to have a ported sub hit nice and low say 20-25 hz with good response for rap and also play nice tight drum bass for say metallica?

Thanks

Ported + Parameteric E.Q. is the most logical setup. You gain the efficiency and increased linearity of a ported subwoofer -- but you can approximate the frequency response of a sealed enclosure and save it in the preset memory to get the 'tight' sound that you want.

The other poster states that low frequency response is deeper with a ported subwoofer. This is both true, but with a catch: The sealed alignement will produce deeper bass response -- when at relative amplitude levels that are under what is audibly significant. Let's examine the response of an example driver, used in a low Q alignment(0.7Qtc) and in a CAD optimized 4th order(ported) alignment.

As you can see, for all practical intents and purposes, the sealed alignment is inferior for low frequency efficiency. The frequencies at which the sealed aligment is responding 'deeper' in this case are under 20hz(and off the graph) and at levels about -20dB from the reference response.

You can use a ported alignment and E.Q. it to taste. The Behringer Feedback Destroyer( http://www.zzounds.com/item--BEHDSP1124P ) is fine for this application. As an added bonus -- you get to improve the room transfer function at the primary listening position.

-Chris