does Flared slots works like flared ports

[Symon_say 10+ year member]

Hi

I'm gonna build a box for my type R 15" really soon, i have never work with flared things but i have design and build some boxes before.

i'm trying tom make it 3.5-4 cu.ft. and about 33hz, my question are this:

1. Arent flared slots suppose to work like flared port, if this is true you can use less port area, like with flared ports.

2. How truth is that a 4" flared port is like a 24 in^2 slot port (this is cause of the flared part).

3. I'm looking for about 50 in2 of port area, what flared ports size and quantity will be like that.

4. And finally for the people that have some experience with type R what box would you recommend for mine.

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[king ranch 5,000+ posts]

i have read on here 12-16sq" of port per cube, with aeros you can do half that so 6-8sq" of port

idk if thats true or not but i have read that on here

 

[Immacomputer 10+ year member]

1) Yes, flared slot ports can reduce port noise like flared round ports.

2) Pretty true. I don't know about the exacts on the numbers but you can get away with less port area with a flared port than a non-flared port.

3) It depends on the flare and how many dimensions you flare.

 

[Symon_say 10+ year member]

1) Yes, flared slot ports can reduce port noise like flared round ports.
2) Pretty true. I don't know about the exacts on the numbers but you can get away with less port area with a flared port than a non-flared port.

3) It depends on the flare and how many dimensions you flare.

Thanks.

I'll make flares in the front and end of the box to make it work like a flared port and reduces overall box size, cause i need as much space as i can get.

With this in mind, can i get away with about the same air speed reduction like the flared port, of about 50% or should i consider about 20-30%.

 

[helotaxi 5,000+ posts]

Figure the percentage change in cross sectional area between the throat of the port and the mouth of the flare. That's the percent reduction in port velocity at the mouth of the port and what allows you to use a smaller port than normal without noise. You also have to use different equations to figure tuning because the mass of the air in the flare has to be accounted for in the tuning. I have the equation for round ports but I haven't converted it for a flared slot.

 

[Symon_say 10+ year member]

Figure the percentage change in cross sectional area between the throat of the port and the mouth of the flare. That's the percent reduction in port velocity at the mouth of the port and what allows you to use a smaller port than normal without noise. You also have to use different equations to figure tuning because the mass of the air in the flare has to be accounted for in the tuning. I have the equation for round ports but I haven't converted it for a flared slot.

Thanks, i'll try to convert the equations i have for flared slots, but as general rule it should be ok to add 1 or 2 in in the lenght of the port for the adjustmen.

 

[mcsoul 10+ year member]

I don't think your going to have a big issue as the type-R 15 recommended port area by Alpine is 1.5"x15". That yields an acceptable .07 port Mach in 3.5 to 4 cubes. How small of a port area where you thinking of? If your looking at 50sq", thats plenty you could get away with 3x16 or even 3x15. Your issue will be the depth (port length) of the port and do you want to "L".

 

[Symon_say 10+ year member]

I don't think your going to have a big issue as the type-R 15 recommended port area by Alpine is 1.5"x15". That yields an acceptable .07 port Mach in 3.5 to 4 cubes. How small of a port area where you thinking of? If your looking at 50sq", thats plenty you could get away with 3x16 or even 3x15. Your issue will be the depth (port length) of the port and do you want to "L".

L is not a big issue, i was gonna do about 12.5x4 for the port, and was looking at the flared thing to reduce that a little bit, so i can get more volume for the box.

 

[mcsoul 10+ year member]

Going from 4x12.5 to 3x12.5 only increases your mach from .03 to .04

in 4 cubes. That sounds fine to me. It also decreases your port length

requirment from 26.21 to 18.52. Sounds like a win/win to me.

//content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif crap I used 32Hz instead of 33, you only need 17.07" @ 4 cubes

and 3"x12.5"

 

[Symon_say 10+ year member]

Thanks, i'll keep the update on the project, i'm planning on build the box this weekend. An i think this will work, cause i just get about 17.7 m/s air speed with the flare, so with the flare that should be a little less.