IB virgin needs help (1 Viewer)

[GregSanders]

I'm new to IB setups and really speaker building in general; however, my first project is underway. I'm building a 5.1 setup and am now working on the subwoofer. My budget is $350-$400 max, and I was decided on a Tempest in a sealed box with the 250W parts express plate amp, until I heard about IB. I have a size constraint of 19"Lx22"Wx30"H if I'm using a box.

People seem to be using a lot of drivers in IB setups, so I'm wondering if this is a function of IB setups needing more displacement or just people being nuts and excessive over bass (ie 4 Tempests or 12 Shivas, or even 2 Tempests). The room in which the setup will go is fairly small (I don't have measurements here), and I was previously under the impression that a sealed Tempest would put out more than enough bass.

With my budget, space constraints, etc, do you recommend IB or sealed with one Tempest?

Thanks in advance,
Greg

 

[Dustin B]

$400 is lots for a dual driver IB. Two of the Parts Express Dayton 15IB drivers and a PE300-794. $220 for the drivers and $130 for the amp totals $350. Leaving you $50 to build the manifold which should be more than enough for that.

The PE IB drivers are single 8ohm voice coils, so parallel the pair and then the 250W plate amp is more than enough power.

 

[GregSanders]

Are 2 15s really necessary in an IB setup? Also, can anyone comment on if and why you'd need more displacement in an IB setup than a sealed one?

Greg

 

[Dustin B]

The more displacement you have, the less you need to push the drivers and lower distortion will be (plus it gives headroom that can be eaten if you decide to EQ up the bottom end if it rolls off to fast for your tastes). A pair of 15s has Rich Kraus tickled pink. So if the funds are there why leave it to chance. Although you could build the manifold so that you can easily add another driver later if one isn't enough.
Have you looked through the back pages of the IB forum (click the link at the bottom of the main page that is in German I think).
http://www.f20.parsimony.net/forum36...sages/1090.htm

 

[GregSanders]

Great, thanks for the reply and the link to the post. I had looked through some of the older pages of the IB forum but not all. I am going to re-evaluate whether I should be doing IB at all and will likely take your advice on the Daytons if I do it.

Thanks again,
Greg

 

[Jack Gilvey]

Also, can anyone comment on if and why you'd need more displacement in an IB setup than a sealed one?

You don't "need" more displacement for a given frequency at a given SPL. However, IB loading (basically a large sealed box)rolls off deep bass at a much slower rate than a smaller (

 

[Pete Mazz]

Let's not forget that 2 opposing drivers will effectively cancel mechanical forces that would otherwise shake, rattle and roll the typical wall or ceiling.

Pete

 

[Ryan Schnacke]

I was all set to post until I saw Jack's and Pete's last messages. They nailed it on the head.

Two of these 15inch IB drivers in 220 cu ft sealed with watts each gives you a frequency response that's almost identical to a single Adire alignment Tempest with 250 watts. That's using WinISD pro. Pretty cool, huh?

 

[Nathan_M]

Guys, read the subject line, this man needs help and doesn't need to be spending time in some attic making speakers.

IB Virgin - Needs Help.

Poor guy, no one has even offered him one shred of relevant information on ways help him out of his present situation. Start with some flowers and a nice bottle of wine.

 

[Jack Gilvey]

Actually, there's lots of good info. there for minds if sufficient grasp, including answers to specific questions on IB.

Anything to offer?

 

[Greg Yeatts]

Nathan_M

I actually got your joke. I think its very funny.

 

[Dustin B]

Since Jack missed it though (don't worry Jack took me a while to get it) makes Jack's post even funnier
Good thing this wasn't in the computer area talking about IP.

 

[Greg Monfort]

>Since Jack missed it though (don't worry Jack took me a while to get it) makes Jack's post even funnier
====
ROTFLMAO! Indeed it does. Since big IBs blow, and suck, it should pop his 'cherry' if he 'feeds' it enough. So pony up for two and have a 'menage a troi'.
GM

 

[Jack Gilvey]

:b Oy...I guess I was tired. :b