Help buying or building 2-way 350hz xo

I would like to take my already made 2-way monitors and make them into a 3-way by adding another driver, ideally I would like to just add a 12Db butterworth XO at 350hz between them and hopefully without issue.

Question - Can I just design it in xsim and build it Or is there one out there I could just buy? And… how hard is xsim to learn / do ( I haven’t even downloaded it yet) if I have to? If no to both could someone just design one for me and I’ll order the parts and build it?


1. See photo - The tops are 2-way HTM12’s (green) and the bottoms are single 18” pa460’s in a 42hz box (Blue).

2. I have been running theses for two years as a 3-way (red) on a nu1000dsp amp (three amps - 6 channels - six speakers). Before eq these are an spl match so no l-pad will be needed, only some light peq will be enough.

3. These will be FULL RANGE (NOT AS A SUBWOOFER) so I WILL BE running the 18” pa’s from box tune (42hz) to 350hz and the HTM’s from 350hz and up.

4. I will be pushing a couple hundred watts to each 3-way…. Let’s say 400-600 for fun, I’m going to mono my nu1000dsp amps for each set.

5. The Htm’s and the pa460’s are 8ohms.


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