Passive Radiator enclosure volume question

[SpeakerBoy 64]

When using a PR in place of a port, you would keep the same internal box volume as the equivalent ported enclosure, correct?

[altoncustomtech 773]

Yes. To expect the same response (or even similar) to that of a standard ported enclosure the size needs to be the same.

What are you looking at doing that's going to use PR's?

[SpeakerBoy 64]

Yes. To expect the same response (or even similar) to that of a standard ported enclosure the size needs to be the same.

What are you looking at doing that's going to use PR's?

Thinking of trying the BTL with two VMP's to save some space in the truck. I was already running short on space with the twelves and fifteens I had, and the BTL box is the biggest yet. Trying to tune low, and keep getting gargantuan port sizes when I try to keep the area big enough to avoid noise.

I don't know a ton about them, but the potential space savings and ease of retuning are extremely intriguing. I'm actually reading that page you have posted somewhere in your build log in another tab.

BUT they are like 250 a piece and i'd like to know more about what i'm doing before just slapping it together.

 

Edited April 5, 2014 by SpeakerBoy

[altoncustomtech 773]

Your BTL is an 18, correct? For the best performance you'll need with a PR larger than it or a pair of 18" PR's.

A PR setup won't save a tremendous amount of space over a standard ported enclosure. It does make it a little smaller though and has a few other advantages such as the easy to change tuning and better transient response. It's not exactly the same but it's kinda like the best if both worlds between sealed and ported.

[lithium 358]

for the way less than the cost of the pr's you could build several boxes with different specs and test out which is best. 

[Tirefryr 1,742]

Find some baskets cheap, get a couple recone kits, and add mass as needed to tune.

[Impious 1,476]

Still way more expensive than standard ported. As Alton said the PR needs to have 2x the displacement of the sub, so you would probably need 2 18" VMP's. I don't see the small amount of space savings being worth the cost.

[altoncustomtech 773]

Absolutely.  The BIGGEST reason I did it in the Jimmy, with only 10's mind you, was because I like doing things that are different, I had never tried that type of setup before, and let's face it having the bragging rights of using the first and so far only XCON PR's is kinda kewl.  LOL  In all seriousness I couldn't even imagine trying to do it with 18's in a vehicle.

 

The 10" PR's that match the XCON's perfectly cost me $90 each.  If I hadn't had the extra money and worked hard to learn to fully understood the pros and cons of using such a setup I wouldn't have even thought about it.

[SpeakerBoy 64]

It's not necessarily the cost itself that concerns me, it's just not wanting to buy something with no idea if it's what I want.

I got a new job, no longer on that IN minimum wage bullshit

Lithium, access to the tools to build boxes is almost nonexistent to me, I'll have to make a four hour drive tomy hometown to have these cuts made. I don't have anywhere to store tools if I bought them, my apartment is fucking tiny. Not to mention I'm not exactly confident in my woodworking skills, I've never used more than a circular saw and a jigsaw to build and it's always left something to be desired, at least aesthetically.

[SpeakerBoy 64]

I'm perfectly okay with not using them as well, but like I said, being able to retune without making any modifications to the box itself is a big motivator, I guess the way I look at it, at the rate I'm always changing my systems and having to find new enclosures, after a few years, I'll have saved on building anyway.

[altoncustomtech 773]

It's not necessarily the cost itself that concerns me, it's just not wanting to buy something with no idea if it's what I want.

I got a new job, no longer on that IN minimum wage bullshit

Lithium, access to the tools to build boxes is almost nonexistent to me, I'll have to make a four hour drive tomy hometown to have these cuts made. I don't have anywhere to store tools if I bought them, my apartment is fucking tiny. Not to mention I'm not exactly confident in my woodworking skills, I've never used more than a circular saw and a jigsaw to build and it's always left something to be desired, at least aesthetically.

 

Four hours???!!!???!!!  You're in Indianapolis for Christ's sake.  There's quite a few members on here that live in and around Indianapolis that I'm sure would be MORE than willing to help you with cutting and building an enclosure.  Hell, for that matter, I'm half that far away (roughly 2-2.5 hrs) and would be glad to help with this kind of stuff.  

 

As for whether or not it's what you want or not you'd need to hear what the two different kinds of setups sound like.  That I'm afraid makes me about the only person that can help you with that unless there's someone else you know who's got a PR setup.  I was thinking doing a C pillar wall with all those 18's would look pretty bad ass and fool the hell out of people like my 10's are doing.  They think they're all real subs until they look through the plexi windows, then the look on their face is priceless, lol.

[Impious 1,476]

It's not necessarily the cost itself that concerns me, it's just not wanting to buy something with no idea if it's what I want.

I got a new job, no longer on that IN minimum wage bullshit

Lithium, access to the tools to build boxes is almost nonexistent to me, I'll have to make a four hour drive tomy hometown to have these cuts made. I don't have anywhere to store tools if I bought them, my apartment is fucking tiny. Not to mention I'm not exactly confident in my woodworking skills, I've never used more than a circular saw and a jigsaw to build and it's always left something to be desired, at least aesthetically.

If you're still in Fort Wayne I have no problem building it for you/with you. I have all the necessary tools. I'm only 30 minutes north of the city.

[SpeakerBoy 64]

I'm in Joliet til june for some court following that drunk running me off the road in January, but yes, I still live in FT Wayne.

I thought about a wall, but, in addition to the change in weight distro, that's a couppppppple more cuts than a box rofl and I'm already struggling there. If you guys in my area would really be up to help, as soon as I get things settled after I'm home that'd be awesome

Hell, if I could get that kind of help, I'd be somewhat willing actually save up for another three 18's for a clamshell. ESPECIALLY if I went with something more budget friendly, like Obsidian.

But I guess I got some more thinking to do, before I purchase anything lol.

Thanks for the quick answers

Edited April 5, 2014 by SpeakerBoy

[Impious 1,476]

I don't have the time for a wall...LOL

But for any other type of install or construction help I have no problem lending a hand or making some sawdust with my tools.

[SpeakerBoy 64]

I'll keep that in mind for when I'm back