Simplexx 15 Ported and Sealed?

Our easiest to build speaker lineup.
Post Reply
Message
Author
santacruznick
Posts: 2
Joined: Sun Feb 02, 2025 5:09 pm

Simplexx 15 Ported and Sealed?

#1 Post by santacruznick »

Hello!

This is my first speaker build and I'm pretty excited about it.
I'm going to build a Simplexx 15 with a tweeter. The speaker will be used as a Bass guitar cabinet, primarily being used in practice space playing classic rock & funk that generally includes drums, electric guitar, and a Rhodes. Every once in a while, it will be used for a small outdoor gig.

I have a question that I could not find directly addressed elsewhere in this forum. I am having a hard time deciding whether to build my cabinet sealed or ported. My question is do I have to make a decision? Can I build a cab that can be played both ported and sealed? I have chosen to use the Eminence BP1525 driver because, at present, I am inclined towards building a sealed cab. That driver is rated for both sealed and ported enclosures. Would it cause any problems to follow the plans to build a ported cab and then fabricate some plugs to obstruct the ports so the cab can be played sealed? I can see it will be harder to plug the ports given they are triangular and not round. I understand the ports would need to be made properly airtight or I would be getting the worst of all worlds.

Has this been done before? Am I barking up the wrong tree?

Thank You!

jimbo7
Posts: 874
Joined: Fri Dec 28, 2012 10:45 am
Location: St. Louis

Re: Simplexx 15 Ported and Sealed?

#2 Post by jimbo7 »

The plans go over sealed vs ported and what drivers he recommends. (I assume you don't have the plans yet)
BFM builds:
XF212
T24 BP102 24"
2x SLA's 6-5" mids, 9- gt-302's
2x AT 14" MCM 55-2421
TrT 5" MCM 55-2421
AT 18" JBL GTO804
2x OT12 flat array
2x SLA Pro 2-Alpha 6's 2-Goldwoods
2x T39 24" 3012lf
Simplex 10 BP102

santacruznick
Posts: 2
Joined: Sun Feb 02, 2025 5:09 pm

Re: Simplexx 15 Ported and Sealed?

#3 Post by santacruznick »

Thanks for the reply. I purchased plans for the Simplexx15. Based upon the list of recommended drivers I chose the Eminence BP 1525 as it is the closest one to the qts specifications recommended in the plans for a sealed cabinet build. However, in the process of selecting that driver, I did notice that the BP1525 manufacturer's specifications list the BP1525 as suitable for ported applications. This got me thinking about whether I could build a cab that can be switched from ported to sealed on the fly, perhaps in response to the situation in which the cab is being used. I.e. type of music, venue etc.

User avatar
Strange Kevin
Posts: 172
Joined: Fri May 19, 2017 3:02 pm
Location: Scottsdale AZ

Re: Simplexx 15 Ported and Sealed?

#4 Post by Strange Kevin »

If your double check the QTS spec on the BP1526 is should be in the range that's recommended for either a sealed or ported S15 cab.
Ported will give you a little more sensitivity on the low end.
You can check the frequency response graphs here viewtopic.php?t=20963
Authorized Builder - Phoenix AZ.
Main Rig - 6 DR200s - 6 T48s (30")
SLA Pros for the smaller stuff.

jimbo7
Posts: 874
Joined: Fri Dec 28, 2012 10:45 am
Location: St. Louis

Re: Simplexx 15 Ported and Sealed?

#5 Post by jimbo7 »

Since the dimension are the same, I don't see why you couldn't made a second sealed baffle and screw it to the ported baffle. Or just some squares to cover the port. The only difference I see in sealed vs ported is the bracing.
BFM builds:
XF212
T24 BP102 24"
2x SLA's 6-5" mids, 9- gt-302's
2x AT 14" MCM 55-2421
TrT 5" MCM 55-2421
AT 18" JBL GTO804
2x OT12 flat array
2x SLA Pro 2-Alpha 6's 2-Goldwoods
2x T39 24" 3012lf
Simplex 10 BP102

Post Reply