Pls help a poor DIYER make a low wind speed! - diyAudio
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Old 18th August 2005, 01:50 AM   #1
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Default Pls help a poor DIYER make a low wind speed!

Hey all,

I love winsed it does its job as good as it could, but some on hear pls HELP ME, I know how to use it but all the subwoofers I plan on Winsed have unbelivibly HIGH win speeds even with 4 - 8 ports up to 2 meters long.

every project i read about has 1 or 2 ports tuneed to 18 - 20hz and length of about 50cm and they dont have wind speed problems AHHHHHHHHHH!!!!

any help or suggestions would be apprecitated!

thx
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Old 18th August 2005, 03:01 AM   #2
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before any one can help you will need to supply some more info

like what brand the driver is. Its T/S paramaters

what box size & port dia . is winisd giving you

what you are trying to make a H/T or Music sub
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Old 18th August 2005, 03:13 AM   #3
mike.e is offline mike.e  New Zealand
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You require a higher area port. Length will increase if tuning is held the same while area is increased.

Use winisd PRO
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Old 25th August 2005, 07:53 AM   #4
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for example:

I need 4 ports 1.2 meters long and even then I still have a maximum wind speed of 17ms (or is that acceptable)

but the point is, that is a lot of pipe and most people (excluding collo) have 1 port that is about 30 - 60cm and they dont complain

or is that just the way and I have to accept it?

most comercial subs have measly pissy little ports and how come they dont WHISTLE? or do they

thanks
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Old 29th August 2005, 04:52 AM   #5
mike.e is offline mike.e  New Zealand
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If you are attempting a tiny box,low tune,high power woofer,then it probably requires an impossible port. Use a PR

http://www.geocities.com/adrian_mack


use winisd pro. Many ports are not necessarily better than one ;-)I myself just use large shelf ports when required.
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Old 29th August 2005, 07:01 AM   #6
DcibeL is offline DcibeL  Canada
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Anything less than 35m/s is perfectly acceptable. I try to aim for 25m/s or less as long as it fits the box. Use a flared port to reduce wind noise or "whistling". Flared ports require an extra inch or so for the same tuning frequency, but I think WinISD can sort that out for you.
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Old 29th August 2005, 06:29 PM   #7
Svante is offline Svante  Sweden
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Yes, as already said, this is what happens if the box is small, and the driver is capable of moving a lot of air.

Use a passive radiator or a closed box.

What driver is it? How big is the box? What is the diameter of your ports?
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Old 31st August 2005, 07:01 AM   #8
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the driver im planing to use: Adire Brahma 15" D2

Ports are 10.2 cm wide

281 litres is the box size and thats not small, or is it
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Old 31st August 2005, 07:30 AM   #9
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Hi kornmong,

Eat less baked beans.

Or, try a single 520 square cm port (if you're using circular, then that works out at about 25.73 cm diameter). I'd use a shelf port instead (someone else mentioned that) of 52*10cm (depending on what size you're planning on having the actual box). Your port would be about 150cm long.

It looks like you're doing simulations at the full 1600W, do you seriously want 120dB at 17Hz??? If so, with the set-up above, you'll be getting a port speed of 22m/s (and you'll never hear that over the sound of the subby). You'll also have 31mm excursion at about 25 Hz and I'd suggest rolling off severely below the 17Hz, otherwise your voice-coil will be mashed.

But unless you're going to be running this in a full size theatre, seriously try simulating it at 110dB max instead. You'll be able to design an easier build (and it'll be easier to power also).
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Old 2nd September 2005, 07:07 AM   #10
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no im doing simulations at 512 watts but thats ok now because 17ms is acceptable but hell 281 litres is huge, sorry for the hassle but ive got a new and cheaper plan, with a smaller box

and I plan to use the DAYTON TITANIC 15" MK3 hell of a lot cheaper

thanks for all the help and suggeations

ive got another question but ill ask in this thread or should I start another? when you say, ill post
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