A:AnswerI used the smaller set on my 2”component speakers. They worked perfect. I would say under 4 “ use the small ones.The bigger ones should be for larger speakers 5 1/4 ‘s or something in that range. Wire to the positive side. My components were rattling and distorting bad When I turned it up loud. These did the trick.
A:AnswerI don't know about the brand, but bass blockers are far from new. They are put in line to block lows from going through your speakers. Like if you don't have crossovers and speaker is getting full range sound, and it's a 6x9, 6.5 speaker and you just want some mid bass and highs (vocals) going to it since maybe you have a subwoofer and don't want bass going through your door speakers you would use these. Also if speaker distorts bc of low frequencies use these. If home audio was what the question was for since doesn't specify it's same concept.