[Rpm Dropping]

You were at an idle. Your alternator puts out less power at an idle than it would at say 2,000 engine RPMS. That could be the solution right there.

[Lanzar Subs]

The Optidrive line is worth their weight. I'm not a fan of their other lines, except the Vibe 1200D.

[Anyone Tried Sonotube?]

Isobaric is great for small box applications, but you can run only roughly half the power to the speakers. I don't know if some of you older guys remember the Advent Temple of Boom. It was 2 10 inch woofers in an isobaric pyramid enclosure.