First, I have not used any of the following software... I simply searched using Google and compiled a few links. Your Results May Vary...
I built the Audax Home Theater speakers and used their published design. The only change I made to the published design was to make cabinet front and rear baffles 1 1/2 inches thick and then to make the front L/R enclosure two inches less deep and a bit over four inches taller (keeping the internal volume the same) to keep them from protruding too far into the room.Results of my Google Search
First, Adire supplies a version of LspCAD for Adire Drivers
that will allow you to design enclosures for their drivers. It is a possibility if you are considering them. I have a 15 inch Tempest Subwoofer waiting for me to find some spare time and a length of 18 inch Sonotube. I'll be using that software to optimize that enclosure.
For other vendor's drivers, you will need a program that either has them defined in their database of driver parameters, or one that allows you to input the parameters of your own drivers.
One of the programs mentioned a lot is LspCAD. The full version is available at this link to LspCAD
. Although it is not free, there is a demo to allow you to determine if it might work for you.
Another possibility I found was Speaker Workshop
It is freeware.
A third I found was Loudspeaker Lab
It seems to have a demo mode you could try.
Yet another loudspeaker design program mentioned often is WinSpeakerz
They have several demo's available for download featuring drivers from several vendors.
One more is winISD
. It is freeware.
A great page I found that listed most of these programs (and a few others) in addition to links of interest to DIY builders was DIY Loudspeaker Resource Page
As you start on your DIY Loudspeaker learning curve, you have plenty to read and absorb. There are support forums to help the beginner... and the experienced. Even after building the Audax HT speakers, I feel like I am a lot closer to "beginner" than "expert." Like you, I leveraged the experience of published and respected "experts" as I started on my project.
Lastly, I am used to hearing the term "bridged" when referring to amplifiers. It is used to double the available peak-to-peak voltage to get more power to the speakers. In that respect, almost any loudspeaker, including the Audax speakers, that has both input terminals isolated from ground may be used.
Hope this helps...