2.1Amp and passive sub sounds bad :-(

I 3D printed Hexibase’s subwoofer enclosure and put in the same Tang Band WS-1876S driver he used. This sounds great on a Dayton Audio KABD amp, but not so great when I plug it into the Sub jacks on the 2.1Amp.

Is the 2.1Amp supposed to use an active subwoofer? Oddly enough, the sub sounds much better when I plug it into the Left Speaker jacks on the 2.1Amp.

I’ve played around with ACPWorkbench and tried to lift up the low end… it only sounds worse.


Sorry to hear that. The Up2Stream 2.1 amp is not supposed to use an active subwoofer. It is supposed to deliver up to 100W (under optimal conditions) to a passive subwoofer. The subwoofer channel works great in my boombox. I used a Tang Band W5-1138SMF plus passive radiator.

Thanks for confirming. I’m sure it’s something I’m doing wrong. I’m brand new to building my own speakers and amps.


One point for your reference, the subwoofer channel has a hardware low pass filter with cutting frequency 300Hz.