Any problems with this WinISD model/design?

[NathanC]

Hello everyone! I'm hoping I can get some help from some of the experienced people here. I've modeled a few different boxes for the SQL 15 driver from stereo integrity. The graphs/outputs I'm able to get seem great but based on some of the other threads I've seen on this forum for this driver, I'm wondering if I've done something wrong.

I've just about settled on a 4.25^3ft boc with a port tuned to ~17hz. I'm unsure how close to xmax I should really allow the drivers to get but model shows spl that I will probably never even want to hit. Usually will be using half this power at most just to be safe and it should still be plenty loud if my understanding is correct. I wanted to try to keep the response as flat as possible as low as possible because it's going in a very large room that probably won't provide much gain.

I have a peq filter at 20hz +4db q=1 with a buttersworth 4th order at 14hz to keep xmax under control below tuning and still keep as much output as possible. The group delay is a little concerning, but from what I've read is mostly a non issue at the frequencies that it's so high at. Right now I have a Bheringer 3000D in mind for the amp. I'll get the 4ohm DVC version of the driver an wire in parallel to 2ohms for the amp. Limit to 27v ~500w(may not make a lot of sense but will give me plenty of headroom). The PEQ may be a bad idea but I'm unsure.

Suppposedly F3 will be ~18hz F6 ~16hz F12 ~13.5hz. Peak excursion right at 26mm at 13 and 25hz. Xmax for the driver is 28.4 so Maybe that's pushing it, I just don't know but also real world will almost never be driving it at these levels. Also db is at 2.2 meters. Air velocity right at 25m/s. That is the part that is probably wrong but I can figure that part out a little better when I actually make a finalized box design once I know I'm okay to move forward.

I originally was going to do a "VTF" dual port design because I thought the idea sounded cool but I realized how little I would ever change the tuning plus how impractical it would be. I can send the modeling I got for those as well if this one is completely wrong, but if that's the case those probably are too.

Thank you to anyone who can take the time to help educate me. I really appreciate it!!

 

[TLS Guy]

Hello everyone! I'm hoping I can get some help from some of the experienced people here. I've modeled a few different boxes for the SQL 15 driver from stereo integrity. The graphs/outputs I'm able to get seem great but based on some of the other threads I've seen on this forum for this driver, I'm wondering if I've done something wrong.

I've just about settled on a 4.25^3ft boc with a port tuned to ~17hz. I'm unsure how close to xmax I should really allow the drivers to get but model shows spl that I will probably never even want to hit. Usually will be using half this power at most just to be safe and it should still be plenty loud if my understanding is correct. I wanted to try to keep the response as flat as possible as low as possible because it's going in a very large room that probably won't provide much gain.

I have a peq filter at 20hz +4db q=1 with a buttersworth 4th order at 14hz to keep xmax under control below tuning and still keep as much output as possible. The group delay is a little concerning, but from what I've read is mostly a non issue at the frequencies that it's so high at. Right now I have a Bheringer 3000D in mind for the amp. I'll get the 4ohm DVC version of the driver an wire in parallel to 2ohms for the amp. Limit to 27v ~500w(may not make a lot of sense but will give me plenty of headroom). The PEQ may be a bad idea but I'm unsure.

Suppposedly F3 will be ~18hz F6 ~16hz F12 ~13.5hz. Peak excursion right at 26mm at 13 and 25hz. Xmax for the driver is 28.4 so Maybe that's pushing it, I just don't know but also real world will almost never be driving it at these levels. Also db is at 2.2 meters. Air velocity right at 25m/s. That is the part that is probably wrong but I can figure that part out a little better when I actually make a finalized box design once I know I'm okay to move forward.

I originally was going to do a "VTF" dual port design because I thought the idea sounded cool but I realized how little I would ever change the tuning plus how impractical it would be. I can send the modeling I got for those as well if this one is completely wrong, but if that's the case those probably are too.

Thank you to anyone who can take the time to help educate me. I really appreciate it!!

To be honest that does not look a very promising driver. It is high Qts (0.57), and has a a very high F3 (33Hz). Generally high Qts drivers are best suited for sealed application, but with an Fs that high it will not be much of a sub in a sealed box. Have you bought it yet? If not, don't.

 

[NathanC]

To be honest that does not look a very promising driver. It is high Qts (0.57), and has a a very high F3 (33Hz). Generally high Qts drivers are best suited for sealed application, but with an Fs that high it will not be much of a sub in a sealed box. Have you bought it yet? If not, don't.

Thank you for the reply, I've seen two different sets of t/s for this driver and think that I read that the ones on the manufacturer site have been confirmed incorrect. Didn't make much sense because I'd think that they'd change them. The other set of parameters I've seen, and what I used in WinISD show Qts (0.42) and Fs of 23.8

 

[TLS Guy]

Thank you for the reply, I've seen two different sets of t/s for this driver and think that I read that the ones on the manufacturer site have been confirmed incorrect. Didn't make much sense because I'd think that they'd change them. The other set of parameters I've seen, and what I used in WinISD show Qts (0.42) and Fs of 23.8

That sounds a lot more promising and I suspect it could be modeled sealed or ported. Those original numbers you posted would make it totally useless as a sub driver. The problem is, you have to ask which numbers are correct? The manufacturers site should have correct numbers, if not it makes you really wonder about their quality control and if they can be trusted to make a consistent product. I would avoid them like the plague if I were you.