How can i calculate the enclosure volume for two parallel fullrange drivers

I will back GM's post up thus:

The Vas doubles so you should double the box volume.

Then you should calculate the port dimensions that tune the doubled volume to the desired frequency.
Hmm, just so we're clear; if inputting the specs for a program to calculate a box alignment, then 2x Vas will automatically double box volume (Vb).
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Paid Member
2004-11-10 8:31 pm
I want to build ported loudspeakers using two parallel Visaton BG20 drivers in each cabinet. How can i calculate the necessary volume of the enclosure?
Thank you for your help
Not only doubling the volume. Ideally, you should divide the internal space by the wall. Just like bose did with nine identical fullranges. You do not want one affecting the cone of the other. Ideally.


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Yeah, I debated about mentioning it, but I've done a lot of multiple driver vented boxes using unmeasured same-same drivers with no issues, not even in prosound where any issues multiply seemingly exponentially.

That said, as good a way as any to add bracing with minimal Vb loss.

As for your example, they apparently had to based on some of the measured specs I've seen. :(

cracked case

2020-07-03 11:44 am
I once tried both stereo channels in one, undivided ported box with no problems. I've made a few speakers with two identical full rangers, if they're wired in series just a cap ( 1.5 uf works well ) solves any problem with beaming, one cap even worked with four drivers in a square.
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