Flared ports...how you do that

[l7runner 10+ year member]

the more numerous and deeper the cuts, the easier to bend.

Its not that hard, just try it

 

[DS Autosports 10+ year member]

soak the mdf in water

lol thats funny //content.invisioncic.com/y282845/emoticons/crazy.gif.c13912c32de98515d3142759a824dae7.gif; it would swell up like a sponge

 

[dr_peeb 10+ year member]

Soooo ... How do you calculate for the curve? i.e. The port has a certain volume without that curved section, and with the curve added the port's volume is larger.

Does it matter?

 

[plugitin 5,000+ posts]

with a 4-5 inch radius its really not to much different for tuning purposes.

 

[Pioneer~Saturn 5,000+ posts]

usually .5" increments between the cuts will make almost any turn but to do it the right way so the cuts all touch and create a single surface on the inside requires some math.

Draw it up on sketchup, highlight the outside of the curved area of the panel and see how long it is, then highlight the inside of the curved area and subtract the inside length from the outside to see how much material has to be cut away to make it perfect..

Then devide by your blade's width and you have the amount of cuts you'll need (if it isnt a whole number just round up)...then you'll need to do the math for the spacing between the cuts to fit the 'X' amount of cuts within the 'Y' amount of length the kerfed portion is on the panel..//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif that would be the perfect way of doing it imo, to get perfectly 'mated' kerf cuts on the inside.

 

[dr_peeb 10+ year member]

with a 4-5 inch radius its really not to much different for tuning purposes.

Just curious. I mean I see mention of 32.5 Hz, which is a pretty accurate number.

FYI ... As an example, that curved section with a 4" radius curve and a height of 12" (using the box picture in OP's original post) adds 41.2 cubic inches to the port's volume. (Same but with a 5" radius adds 64.4 cubic inches).

Seems like a lot to me.

I'm not even sure how curves vs square corners affect tuning. Maybe the fact that this is a curved section negates the added port volume?

 

[Pioneer~Saturn 5,000+ posts]

Just curious. I mean I see mention of 32.5 Hz, which is a pretty accurate number.
FYI ... As an example, that curved section with a 4" radius curve and a height of 12" (using the box picture in OP's original post) adds 41.2 cubic inches to the port's volume. (Same but with a 5" radius adds 64.4 cubic inches).

Seems like a lot to me.

I'm not even sure how curves vs square corners affect tuning. Maybe the fact that this is a curved section negates the added port volume?

When doing port calculations, neglect the flared portion...so port area is the same, it's just a little bit shorter so your tuning will raise...which means you'll need to compensate by adding a few inches to the length.

The flare will also cut a bit off of your airspace, so you may have to adjust your dimensions and port length when adding a kerf to a design..

And port volume has nothing to do with tuning, fyi

 

[WrenchGuy 10+ year member]

Although great looks come out of it is it more for flow or less port noise?

Prolly 2 bird with one stone I'd think. Its bad *** none the less.

Even if they don't touch we always have resin and mat around...lol

 

[dr_peeb 10+ year member]

When doing port calculations, neglect the flared portion...so port area is the same, it's just a little bit shorter so your tuning will raise...which means you'll need to compensate by adding a few inches to the length.
The flare will also cut a bit off of your airspace, so you may have to adjust your dimensions and port length when adding a kerf to a design..

And port volume has nothing to do with tuning, fyi

Ports have specific height & width (aka area) and depth (the part of the port that is typically inside the box), no? That's volume, no? If volume doesn't matter, why not just leave off the part of the port that's inside the box?

 

[WrenchGuy 10+ year member]

area and length the volume has to be accounted for

 

[Pioneer~Saturn 5,000+ posts]

Ports have specific height & width (aka area) and depth (the part of the port that is typically inside the box), no? That's volume, no? If volume doesn't matter, why not just leave off the part of the port that's inside the box?

I meant when calculating the tuning of an enclosure you need 3 things:

-Net airspace

-Port area

-Port length

So in a way, yes...the port volume will effect the enclosure but you never use the volume of the port in the math itself...just the two numbers involved with the port.

 

[denim 5,000+ posts]

i thought all you had to do was look at the mdf thumpper...!?!?

The title of his movie is: "Men who stare at MDF!" //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif

 

[Pioneer~Saturn 5,000+ posts]

The title of his movie is: "Men who stare at MDF!" //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif

Haha!

 

[mbrooky 10+ year member]

soak the mdf in water

hahaha...then once it dries you'll have 2" mdf for the price of 3/4...//content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif

 

[DS Autosports 10+ year member]

Does eliminating the 90* angles inside the box help the end response? For instance the box in my original post had braces placed on all corners.