bandpass subwoofer

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hello all,
I would like to use a dayton 6.5 inch woofer for a 4th order bandpass and was wondering anyone has done this before with success. I was going to use 2 of the woofers in a single enclosure in attempt to increase efficincy.


Thank you,

Opie
 
Ex-Moderator
Joined 2002
Hi Opie

In general bandpass boxes work great for HT, but not so good for Hi-Fi, due to the phase changes caused by the large group delay of the system. This is caused by the multiple air loads driven by the speaker.

Just think of a weight hung from loads of springs working at angles, and how hard it would be to get it oscillating at one frequency, and then how hard it would be to stop it again... This is what the driver has to do.

However, for HT, it will only be reproducing things like explosions and other FX, and these are rarely mixed to need any vital phase response. In this case, they can be small, hidden and convenient, and work quite well.

I noticed you will be using 2 drivers, that is good, because they are not very sensitive. Despite what the graphs may show, you also need to use a low pass filter to get rid of troublesome mid range frequencies.

This any help?
 
The Dayton will work in both, but it's a matter of accuracy. A 4th order bandpass is hard to get right and a 6th order is very hard!

I wouldn't tackle a 6th order unless you have access to some test kit that can measure the T/S params as well as the frequency response. Good quality drivers usually have +/- 20% spec variations and I wouldn't be surprised if Dayton were more like 30 -> 40%. The higher the order, the more critical your adherence to the specs become.

Most of the cheap bandpass car subs have ghastly one-note bass because people put generic drivers in pre-built boxes without any thought of the consequences.

Nice one,
Davd.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.