3.5 cu.ft , port 4"x21.26" = ?? Velocity - Home Theater Forum and Systems - HomeTheaterShack.com

Old 03-31-12, 12:36 PM Thread Starter
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3.5 cu.ft , port 4"x21.26" = ?? Velocity

Trying to find adequate PORT for this Enclosure SS 315 HO-44 in 3.5 cuft net with 500w tuned to 20hz .
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Old 04-01-12, 06:35 PM
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Re: 3.5 cu.ft , port 4"x21.26" = ?? Velocity

Quote:
randyc1 wrote: View Post
Trying to find adequate PORT for this Enclosure SS 315 HO-44 in 3.5 cuft net with 500w tuned to 20hz .
Have you tried modelling it in winISD yet?

Don't underestimate us! Whether it be time, space, or alternate realities, they mean nothing to us! We will pierce the path and methods you've chosen! That is who we are!
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Old 04-01-12, 06:53 PM Thread Starter
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Re: 3.5 cu.ft , port 4"x21.26" = ?? Velocity

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GranteedEV wrote: View Post
Have you tried modelling it in winISD yet?
No, sorry dont have that software yet .
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Old 04-02-12, 08:15 AM
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Re: 3.5 cu.ft , port 4"x21.26" = ?? Velocity

If you're using 4" round ports then you'll need two of them each being 45" long.
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Old 04-02-12, 12:15 PM Thread Starter
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Thanks Mike P, Wow, very long and will consume to much int vol , did u calculate 2 to get port velocity down?

I've been trying to find a 5" port instead of the (1) 4" to get port velocity down,... i calculated it (1) 5" at around 40 inches long, but have no idea if port velocity would be acceptable ??

I'm allready at my max acceptable Ext Vol, If the 5" (if i can find any ?) dont work i might have to think of going sealed .
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Old 04-02-12, 12:42 PM
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Mike

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Re: 3.5 cu.ft , port 4"x21.26" = ?? Velocity

Quote:
did u calculate 2 to get port velocity down?

Yes, one port isn't enough.

A 5" port would be 34" long for a 20 hz tuning, you may find a cardboard tube in that diameter. A slot port may be your best option. What are your external cabinet dimensions?
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Old 04-02-12, 06:08 PM Thread Starter
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Re: 3.5 cu.ft , port 4"x21.26" = ?? Velocity

Quote:
Mike P. wrote: View Post

Yes, one port isn't enough.

A 5" port would be 34" long for a 20 hz tuning, you may find a cardboard tube in that diameter. A slot port may be your best option. What are your external cabinet dimensions?

At 5" it's still not big enough for port velocity ??? I used a Port Calculator for 3 cuft, (1) 5" port, 20 hz and it came to 40.44 " long ??

Box Dim: Have u ever seen "Tarkus" on Parts Express forum, very similar but bigger :H27 x W15.5 x D23.5 (top 19.5)
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Old 04-02-12, 06:59 PM
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Mike

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Re: 3.5 cu.ft , port 4"x21.26" = ?? Velocity

Quote:
At 5" it's still not big enough for port velocity ???

5" diameter is fine.

Quote:
I used a Port Calculator for 3 cuft, (1) 5" port, 20 hz and it came to 40.44 " long ??
The thread title says 3.5 cu.ft., that's what I based my calculations on.
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Old 04-02-12, 07:41 PM Thread Starter
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Re: 3.5 cu.ft , port 4"x21.26" = ?? Velocity

Quote:
Mike P. wrote: View Post

5" diameter is fine.

The thread title says 3.5 cu.ft., that's what I based my calculations on.
Sorry my mistake, it is 3cu.ft net

Thanks Mike for helping, now if i can just find a 5" PVC pipe .
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