46194
From: Wayne, [ool-182d01b8.dyn.optonline.net]
Subject: Isobaric loading in vented box
|
I am trying to build a Vented box with 2 woofers. I know when you isobaric load the box size is half. I wanted to know if I keep the same port size if I was building for 1 woofer or does that change? Thanks Moderated By: brian@diysubwoofers.org |
46195
From: andrewt, [host86-154-209-21.range86-154.btcentralplus.com]
Subject: Re: Isobaric loading in vented box
|
when you change the box size the port length needs to change slightly to maintain the same tuned frequency. Isobaric loading changes the box size to 50% and will require a small but significant change in the port length. But you can use port length tuning to better match the speaker to the room. Leave the port at least 20% too long and try cutting it shorter to hear what these different tunings sound like. You can buy adjustable length ports. |
46196
From: Wayne, [ool-182d01b8.dyn.optonline.net]
Subject: Re: Isobaric loading in vented box
|
The box I have is 3.5 cubes with 2 4"inch ports at 13.25 long. Now for my Isobaric dual reflex bandpass the both woofers are in the 3.5 cube instead of 7 cube? Will I still be using the 2 4" ports for each side? Thanks for the quick reply Moderated By: brian@diysubwoofers.org |
46213
From: Brian, [65.48.136.161]
Subject: Re: Isobaric loading in vented box
|
This might help... If you're going isobaric: 1.Decrease NET box volume by 50% (compared to alignment using ONE woofer) 2. Fb should remain the same (this will mean that you will have to use longer ports). |
Responses:
None
46197
From: andrewt, [host81-129-18-43.range81-129.btcentralplus.com]
Subject: Re: Isobaric loading in vented box
| Oh! It's a bandpass, I have never designed a bandpass. |
Responses:
None
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