What drivers are they? If car subs, you might find the details you need are not published. If winisd doesn't already have them listed, you need to add them to your own drivers list. Along with all that data from the manufacturer.
I'm in the middle of a build using jbl 1214 subs. One in a box around 95 liters will be 3db down at 22hz, but flat down to 30hz and only 1db down at 25hz. It uses a 100mm port, 360mm long. Give or take a few mm as I'm not actually looking. That's a 23.95hz port.
Interestingly I pulled out my magazine cover bass test cd's to find no tones below 30hz on offer. A tone it produced as loud as any other in my listening environment. It seems in boy racer land, 20hz doesn't really matter. It's for pipe organs.
I'm in the middle of a build using jbl 1214 subs. One in a box around 95 liters will be 3db down at 22hz, but flat down to 30hz and only 1db down at 25hz. It uses a 100mm port, 360mm long. Give or take a few mm as I'm not actually looking. That's a 23.95hz port.
Interestingly I pulled out my magazine cover bass test cd's to find no tones below 30hz on offer. A tone it produced as loud as any other in my listening environment. It seems in boy racer land, 20hz doesn't really matter. It's for pipe organs.
If it's for car audio, my current design rules are as follows:
1. Make sure that you have EQ available with bands around 1.5*Fb, Fb and 0.6*Fb, e.g. 50 Hz, 31.5 Hz, 20 Hz.
2. Design the box so it's vented at Fb. If you don't know what Fb to use, choose 30~32 Hz. 1.5 cu.ft. to 2.0 cu.ft. should be fine for most 12" drivers.
3. Fix the in-car response using the EQ. You'd want to use the lowest band to cut all frequencies below Fb, and the other two bands to flatten the response of the subwoofer down to Fb. Note: You should never have to BOOST the 1.6*Fb band. Cut the response at Fb instead.
1. Make sure that you have EQ available with bands around 1.5*Fb, Fb and 0.6*Fb, e.g. 50 Hz, 31.5 Hz, 20 Hz.
2. Design the box so it's vented at Fb. If you don't know what Fb to use, choose 30~32 Hz. 1.5 cu.ft. to 2.0 cu.ft. should be fine for most 12" drivers.
3. Fix the in-car response using the EQ. You'd want to use the lowest band to cut all frequencies below Fb, and the other two bands to flatten the response of the subwoofer down to Fb. Note: You should never have to BOOST the 1.6*Fb band. Cut the response at Fb instead.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.