4th order design 2 alpine type r 15's

[4bannger 10+ year member]

That one looks better. Would an external port be possible in your vehicle? It would be easier to adjust tuning and port area on if you desired.

Yes it would be I have a SUV and I took out my third row so I have Max room of like 47x50 I'm gonna revise the design one more time and put the adjustable port external and onto of the box to be more esthetically pleasing (well to my taste) and your right. It would be easier because changing the port length and volume would change the overall volume and effect my ratio and tuning if I'm right?

 

[SounDrive Pro Seller]

Yes it would be I have a SUV and I took out my third row so I have Max room of like 47x50 I'm gonna revise the design one more time and put the adjustable port external and onto of the box to be more esthetically pleasing (well to my taste) and your right. It would be easier because changing the port length and volume would change the overall volume and effect my ratio and tuning if I'm right?

Yes that's correct. Having an external port makes sure that you won't be changing the volume.

 

[4bannger 10+ year member]

Yes that's correct. Having an external port makes sure that you won't be changing the volume.

thanks learning a lot from you and all the other helpful people on this forum. I knew i could find someone knowledgable enough to help me with this. this is the final design here the tuning is the same, port size same except for length

 

[SounDrive Pro Seller]

thanks learning a lot from you and all the other helpful people on this forum. I knew i could find someone knowledgable enough to help me with this. this is the final design here the tuning is the same, port size same except for length

Where will the port be firing? Towards the rear I'm assuming?

 

[4bannger 10+ year member]

Where will the port be firing? Towards the rear I'm assuming?

firing up towards the headliner.

 

[SounDrive Pro Seller]

firing up towards the headliner.

It may be louder with a surface to load off of. Port back (or on the side depending on the vehicle) usually works well.

 

[T3mpest 10+ year member]

yeah I would NOT do port up in an SUV, especially in a 4th order. Many times upfiring causes nulls in upper bass response and that's really going to limit how high you sub will play if you have a sharp null like that, usually it's around 60hz. The low end tends to be better when you fire directly off the rear too, so you'd be screwing yourself on both fronts. My SUV is sub up port back right now, but since my subs can play upper bass no problem, I'll be doing sub back port back here very soon.

 

[4bannger 10+ year member]

It may be louder with a surface to load off of. Port back (or on the side depending on the vehicle) usually works well.

well weather i was to fire it at the hatch door or at the roof i would have the same about of space between the port and door and roof

yeah I would NOT do port up in an SUV, especially in a 4th order. Many times upfiring causes nulls in upper bass response and that's really going to limit how high you sub will play if you have a sharp null like that, usually it's around 60hz. The low end tends to be better when you fire directly off the rear too, so you'd be screwing yourself on both fronts. My SUV is sub up port back right now, but since my subs can play upper bass no problem, I'll be doing sub back port back here very soon.

Yeah ill take some quick measurment and see whats up. Thanks for the suggestion. I knew that to be true subs but not ports.