Good source for 6" port, and, is flare necessary? (1 Viewer)

[Trenton McNeil]

Punching my values into WinISD its looking like 2 4" ports
or one single 6" port will work much better for my sonosub
design...I'm having trouble locating a 6" flared port however,
and was wondering if the flaring is really necessary with a
6" port, or if I could just use basic PVC?
Tempest driver
10 ft^3
24" diameter tube
with a single 6" port 16 1/4" long, vent mach hits 0.12
with two 4" ports 15 1/2" long, vent mach at 0.07
single 4" port 6 1/4" long returns vent mach of 0.28!! that
isn't gonna be acceptable...
thoughts, ideas, HELP? I would like to track down the port
before this weekend...
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I wish I had a dollar for every time I spent a dollar, because then, yahoo!,
I'd have all my money back. -- Deep Thoughts, by Jack Handey

 

[Marc_D]

Here is a link for flared ends for 6" ports. Link Removed
Hope this helps.
Good luck tracking them down.
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[Chris Hoppe]

It looks like the two 4" ports would be a better idea anyways... Then you can use regular 4" PVC pipe. I think the vent mach on the single 6" is rather high.
If you use double thick endcaps, you can make the hole on the outside piece the size of the inside diameter of the port. That way, the last 3/4" of your port will be made of wood, and you can use a 3/4" round router bit to flare your port.
I did a similar design for an Eclipse 8815 with a similar volume, and I found that three 4" ports worked wonders!
As long as you have the room for them, there are great gains to be has by keeping that port speed down as low as possible...

 

[Greg Monfort]

>Punching my values into WinISD
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That's a mistake!
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>and was wondering if the flaring is really necessary with a
6" port, or if I could just use basic PVC?
====
Flaring isn't of any audible advantage until mach speed is > 5% (.05), or 56.5ft/sec (17.22m/sec), and since the flare rate needs to increase with increasing mach, you rapidly reach a point of diminishing returns, and still be able to fit the flare on the baffle.
====
>Tempest driver
10 ft^3
24" diameter tube
with a single 6" port 16 1/4" long, vent mach hits 0.12
with two 4" ports 15 1/2" long, vent mach at 0.07
====
Since two 4" have less cross sectional area than one 6", the 6" will have a slightly less vent mach, therefore WINISD is wrong.
Either one flared 6", or three flared 4" would be my choice.
====
>single 4" port 6 1/4" long returns vent mach of 0.28!! that
isn't gonna be acceptable...
====
It's more like 0.18, but still too high for me, even if flared.
Ditch the program, as it's too inaccurate.
GM
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Loud is beautiful, if it's clean

 

[Trenton McNeil]

WinISD too inaccurate? Okay....so what is more accurate?
?!
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I wish I had a dollar for every time I spent a dollar, because then, yahoo!,
I'd have all my money back. -- Deep Thoughts, by Jack Handey

 

[Jack Gilvey]

Trenton,
LSPCad, which you can get over on the Adire site, is more accurate, and comes already loaded with Adire drivers' specs. It's not as easy to use,though. At least for me. Worth getting used to,though.
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Link Removed
"No,ma'am, I'm not the Pumpkin King. Lots of people make that mistake,though."

 

[Trenton McNeil]

Difficult to use is an understatement.
Guess I'll break it back out and see what I can come up with.

 

[Chris Popovich]

So back to those 6" port flares, do they work on standard PVC? If not, then what is used for the cylindrical port material itself?
Thanks,
Chris

 

[Jack Gilvey]

Chris, this retailer's page states the 6" flare kit uses standard 6" PVC pipe.
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Link Removed

 

[Trenton McNeil]

LPScad ain't so bad....I just ignore the room measurement stuff since my living room is so strangely shaped.
Gonna goof around with a few more models before I put this thing together. Thanks to everyone for their input/ideas.

 

[Patrick Sun]

FYI, I located 6" wide PVC pipe, roughly 3/8" thick at Apex Supply in Atlanta (for those in the area). There are quite a few of them in the area, so get the phone book and call around (business white pages work well). It cost me about $18 for a 10 foot section (had it cut down in two 5 foot sections to haul it back home. The inner diameter was spot on at 6" wide, and its overall width was 6 11/16".
Now, that 6" flared port flange kit from Tune Town intrigued me, but the website doesn't list prices for the flanges. Grr... If the price was reasonable, I'd order a flange pair, but just use one on the inside, and on the endcap just sand out a flare with the outer 3/4" MDF. But that's just me typing outloud.
You'd think going from a 4" wide port to a 6" wide port would be a subtle change, but it's pretty substantial IMHO. Girth matters.
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PatCave ; HT Pix ; Gear ; Sunosub I + III ; DVDs ; Link Removed

 

[Trenton McNeil]

Pat, it looks like you really shouldn't have much problem
using a 6" port with port noise even if used without the
flared port opening, it might be purely academic at this
point.
I'm probably going to go with 2 4" ports, non-flared.
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I wish I had a dollar for every time I spent a dollar, because then, yahoo!,
I'd have all my money back. -- Deep Thoughts, by Jack Handey

 

[Julian Data]

Patrick,
Unless you plan to extract every minute dB... talk tenths here, then go for the Flare port but if you don't listen "loudly", I wouldn't bother..
Although, tenths add up to a dB
Julian

 

[Patrick Sun]

"...if you don't listen 'loudly'"? Pshaw!
BTW, I'm at work right now, being the voice of my company, I'm having to record the new name of the company for the auto attendant in the wee hours of the night. Yee-ha!
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PatCave ; HT Pix ; Gear ; Sunosub I + III ; DVDs ; Link Removed

 

[Andrew Pratt]

Trenton for my sub thats very similar to what you're building I ended up using three 4" ports. I wanted to make sure i was safe and I couldn't find 6" pipe that was viable to use (very costly compared to 4" stuff) At the volumes I've been able to stand I've never heard my ports but then I am not giving it goobs of power either.
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The Pratt Home Theater

 

[Neil Joseph]

I was faced with the same dilemma of using 2x4" or 1x6" ports. As I could not readily find 6" port, I decided to go with dual 4" with no flares (I am using 350W rms for power). Not only that, a 6" port would have to be longer and it would not fit in my enclosure, even with elbows.
orangeman
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