I use that same Fosi Audio TP-02 Sub amp. I use it to feel my bass with my DIY Bassboard... since I play ampless with IEM's. It's a great sub amp... been using it for years and never had to replace it. I mounted it in my wireless rack...Timing with my Elac speakes coming, my TV JBL soundbar died, had a look for a fix and possibly just replacing 2 voltage regulators for $25 (shipping and all). Or take the outgoing Q Acoustics BT3 and convert the wireless sub. I was hoping the wireless receiver inside was a easy removable board where I could get to the analog signal pins easy, but was all surface mount. Got lazy and ordered + some speaker cable and termination posts locally.
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My stage setup with bassboard:

BTW... the stock power supply doesn't give you the full 220 Watts. You will have to get a 10A 240W Power Supply Adapter to get the full 220W.