Yes

Oh, the Rockford P300 is a sealed sub with built in amp. I thought it was just an amp. A Key 500 is probably out of their price range.

I found that sealed enclosures in the back of a SUV tend to have very narrow bandwidth. Have you guys found the same to be true?

We use Stinger at the moment

Knuconceptz Krystal are great bang for the buck

No, not at all.

@@JasonWW2000 how though? Doesn't DC voltage move the speaker in one direction? Like if you put a 9v battery on a speaker to check polairty it moves the speaker out in the + direction it moves the speaker in for the - direction

Signal on a speaker wire is AC. The DC offset is just a 6 volt DC signal on at all times from the cheap "chip" amp built into a headunit

​​​@@jdipo16I think I see the confusion. There is not a DC signal going across the two speaker wires. Either one or both of the speaker wires has the positive 5 or 6 volt signal, but the circuit has to go through the amplifiers ground cable. This is why when you're checking for the DC signal you put one probe on a speaker wire and the other to chassis ground. That's the only way you're going to see it. Only a special circuit built into the amplifier can detect that DC offset signal. The speakers are completely unaffected.