I was wondering what the difference in performce is between the JBL 2446H horn driver and the JBL 2451H/J horn driver? The 2446 lists for $732 and weights a bit over 30lbs. while the 2451 lists for $1,315 and weighs only 10 lbs. Quite a difference in cost and weight. Is the 2451 that much better or just has a different purpose?