Was also looking into outlaw 7000 would that be the same thing as the Emotiva Bass X?
The Outlaw likely have a larger power supply, but I am thinking of the Hypex based class D amps, such as the NC252MP based ones.
Your RX-A860's preouts are not adequate for those power amps that have a few dB lower gain than Emotiva's and the AVR's build in amps. The AVR-X6700H will have no problem outputting 2 V or higher, at very low distortions.
Sorry, it will cost you a lot of money but if you want the SVS Utra towers to do their best, you do have to upgrade, unless you don't listen loud, and don't sit too far, such as not more than 8-10 ft.
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