Well actually the PB-10 replaced a Dayton Sub-120, the PB13 replaced a 20-39 PC+, then I wanted to keep the PB-10 for a small 2.1 system I have, but it's amp doesn't have speaker level inputs, and my receiver for that system doesn't have an lfe out jack, so I sold the PB10 and moved the 20-39 PC+ to the bedroom. It's a bit overkill for the size room it's in, but in the 16 hz. tune mode it rocks hard, I love it! But it arrived by ground freight with just one person, which kinda surprised me.