Need help choosing a driver and a horn design.

[italynstylion]

Also, I keep hearing that MDF is a poor choice for wood. Aside from pneumonia and other lung ailments from the dust, why is this?

 

[planet10]

Can the triangular prism deflector...That deflector is almost big enough to house a 12" sub.

I have a picture explaining some of the stuff. Please excuse the use of MS paint

You can enlarge the delector by a bit, but too much may well force you to push the horn too far out from the wall... you may not need the bass, but you would still get the ripple from an untermiated mouth. I wouldn't make it more than 2-3" deeper.

The name of a deflector turned into a woofer is a stealthWoofer.... due to the corner loading a 12" is probably overkill... our stealthWoofer uses a single CSS SDX7.

In the sketch, the triangle with the 66 degree angle is the projection of the optional angled bit if you slant the top. For a woofer i would just extend the prism as tall as you need.

dave

 

[planet10]

Also, I keep hearing that MDF is a poor choice for wood. Aside from pneumonia and other lung ailments from the dust, why is this?

It sounds bad.

As well each material really requires a different box design approach. The FH (as with ost horns) are designed with the characteristics of hi-ply void-free plywood.

dave

 

[chrisb]

In the sketch, the triangle with the 66 degree angle is the projection of the optional angled bit if you slant the top. For a woofer i would just extend the prism as tall as you need.

dave

It's certainly a helluva lot easier to built the flat top than the angled top version.

 

[italynstylion]

You can enlarge the delector by a bit, but too much may well force you to push the horn too far out from the wall... you may not need the bass, but you would still get the ripple from an untermiated mouth. I wouldn't make it more than 2-3" deeper.

The name of a deflector turned into a woofer is a stealthWoofer.... due to the corner loading a 12" is probably overkill... our stealthWoofer uses a single CSS SDX7.

In the sketch, the triangle with the 66 degree angle is the projection of the optional angled bit if you slant the top. For a woofer i would just extend the prism as tall as you need.

dave

Dave, when you say 2-3" deeper are you referring to the length from the tip that faces the horn mouth? I just want to make sure.

I realize a 12 is probably overkill but I'm typically known for that. I already have the power on tap and the speaker so it's a no brainer; why would I spend more money to get less. I doubt I'll ever use it to it's potential but in the event that I do it will likely put a smile on my face.

It sounds bad.

As well each material really requires a different box design approach. The FH (as with ost horns) are designed with the characteristics of hi-ply void-free plywood.

dave

I found birch hardwood at Lowes today so I will go with that. The designs didn't specify the thickness of the wood to be used and it is throwing me for a loop. I was able to deduce the thickness of the outer panels to be 18mm. Unfortunately the insides of the horn appear to be a different thickness but the plan doesn't say what that thickness is. Can anyone help me on that?

It's certainly a helluva lot easier to built the flat top than the angled top version.

Yes, that's what I intend to do but I think I'm having trouble reading the plans. The angle of the point that faces into the horn mouth is intended to be 75.4 degrees; correct? Also, is this angle alterable?

 

[italynstylion]

Sorry if I'm asking a ton of questions. I've got about 10million ideas blasting through my head and I just want to see if any of them will work.

 

[planet10]

Dave, when you say 2-3" deeper are you referring to the length from the tip that faces the horn mouth? I just want to make sure.

Yes...

I realize a 12 is probably overkill but I'm typically known for that. I already have the power on tap and the speaker so it's a no brainer; why would I spend more money to get less.

My fear is that you'll not be able to achieve optimum volume... do you have 2 12s?

I found birch hardwood at Lowes today so I will go with that. The designs didn't specify the thickness of the wood to be used and it is throwing me for a loop. I was able to deduce the thickness of the outer panels to be 18mm. Unfortunately the insides of the horn appear to be a different thickness but the plan doesn't say what that thickness is. Can anyone help me on that?

Dimensions are in the notes on page 3, 12 &18mm as drawn. If you want to do it as a single thickness i'd recommend 15mm (5/8")

dave

The angle of the point that faces into the horn mouth is intended to be 75.4 degrees; correct? Also, is this angle alterable?

Yes... Ron spent a lot of time getting that angle just right... any deviation will move it from optimal.

dave

 

[italynstylion]

My fear is that you'll not be able to achieve optimum volume... do you have 2 12s?



Yes... Ron spent a lot of time getting that angle just right... any deviation will move it from optimal.

dave

I do have 2 12's...ideally, one for each of the deflectors. I'm a symmetry guy and I'm not afraid to admit it bothers me when things aren't balanced.

The volume will not be hard to achieve since I'm only looking for .75cubic feet. The driver I'm using doesn't require a large box. If I need more volume I can just make the deflector taller right?

The only hiccup I have in the plan is that the top face will not be big enough to mount a 12 in since it wont even have a side that is 12" long. It's going to be a problem...and that's an understatement.