The inuke doesn't really put out 2000 per channel. More like half that. Also the Dayton's wired together make a 2 ohm load. The inuke 6000 doesn't do 2ohms. The best match for two dual oppsed Daytons is something like a Marathon 5050. The Stereo Integrity 18's can be wired so as to match up with the inuke6000.
The 6000 could power two single Dayton 18's
Either way, you are really better off selling the ultra and building two new subs if you don't want to buy another ultra.
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