Pretty simple question just checking my train of thought

[coldcathode]

Ok,


So a typical Ported/Bass Reflex enclosure rolls off below the tuning frequency at about 24db/Octave correct?

So, a driver/cabinet that has an F3 of about 65hz would mate up well to a sub woofer with a 24dB/octave low pass at about the same 65 hz assuming a linkwitz type alignment??

The hypothetical is this:

Assume the overall sensitivity of the sub and woofer were identical in relation to the power supplied, would a 24db/octave low pass active crossover for the sub and the accompanying acoustic roll off of the ported box for the mid form a Linkwitz aligment response?

 

[gfiandy]

If you have a ported enclosure the port resonance should be at the driver enclosure resonance. If this is the case and you have a F3 65Hz and a Q of approx 0.5 then a sub with the same characterisitcs should form and approx L-R alignment. However due to phase issues really you need to measure this and adjust for the actual installation.

Regards,
Andrew

 

[coldcathode]

Andrew,

Thank You,

I realize that it is all "hypothetical" since Phase is a concern esp. around the Xover frequency. I was more concerned with a good starting point in laying out my system and making sure my "train of thought" was on the right track.

thanks again

 

[whgeiger]

Not Simple

Ok,


So a typical Ported/Bass Reflex enclosure rolls off below the tuning frequency at about 24db/Octave correct?

So, a driver/cabinet that has an F3 of about 65hz would mate up well to a sub woofer with a 24dB/octave low pass at about the same 65 hz assuming a linkwitz type alignment??

The hypothetical is this:

Assume the overall sensitivity of the sub and woofer were identical in relation to the power supplied, would a 24db/octave low pass active crossover for the sub and the accompanying acoustic roll off of the ported box for the mid form a Linkwitz aligment response?

Below f3 the driver in the BR cabinet becomes unloaded, and the signal to it should be HP filtered as well to prevent damage to it by the LF going to the sub as well.

Regards,

WHG

 

[coldcathode]

Below f3 the driver in the BR cabinet becomes unloaded, and the signal to it should be HP filtered as well to prevent damage to it by the LF going to the sub as well.

Regards,

WHG

So what f3 for the HP section?

 

[whgeiger]

SWAG

So what f3 for the HP section?

100>[f3]>65 Hz. and plug the port,
or
[f3]<65 Hz with port open.

With a little testing, it should become apparent which solution best matches the specifics of your system.

Regards,

WHG