4th order bandpass with an IB sealed chamber?

[ThyDntWntMusic]

Modelling this in Winisd.

How is a 4th order with an "infinite" sealed chamber any different to a ported box?

Cone excursion models the same, but the frequency response suggests there will be an 8dB gain at 18Hz.

Is this actually going to be the case?

The "port gain" graphs for the two enclosures are basically identical?

 

[chris661]

The difference is that with a ported box, you're listening to driver & port combined.

With a 4th order bandpass, you're only listening to the port output.

Chris

 

[ThyDntWntMusic]

..yes, so why is listening to just the port, 8dB louder?

 

[chris661]

Because, at some frequencies, the driver & port cancel each other out.

Chris

 

[manninen]

How this is build? 150l/30hz box into wall and magnet can be seen other side of the wall?

 

[ThyDntWntMusic]

How this is build? 150l/30hz box into wall and magnet can be seen other side of the wall?

My intention was under the floor, but wall would also work.... depending who/what is on the other side... haha

 

[TBTL]

With a 4th order bandpass box, the tuning frequency is at the centre of the pass band (useful frequency range).
With a ported box, the tuning frequency is at the bottom end of the pass band.


How about a regular infinite baffle setup? That will save you 150 L of box size.