Good morning everyone. I just have a question about this A/B speaker button that you find on an amp or receiver. I understand that you use it if you got two sets of speakers and that is also a good tool for comparing or testing speakers. My question is, is it possible to use both A/B button at the same time? So my main speakers is hook up on speaker terminal (A), then I will tap into the amp speaker terminal B using its signal to connect my subwoofer using the high level speaker level input. I heard this is the best way to get extension of your bass coming from your speakers. Any input please. Thanks.