Today i Just got my 10W7 installed with my Alpine 600W amp. My HU is a 4 Volt Preout. When i set my amp to 4.0V gain, it barely moves the W7, but when i set it to 1.0V it starts to really make a nice difference. why does the alpine instruction manual tell me to match the gain to my preout Voltage on my HU? It sounds way louder and better at 1.0V
the 8, 10, and 12 can only be wired at 3 ohms. they are 3 ohm SVC subs.
start with the gains all the way down and play whatever music you normally listen to thats got some bass in it. turn the HU up 3/4 of the way, then slowly adjust the gains up till the sub starts to distort or you get enough bass for your tastes. thats what i always do.
but you are prob under powering the W7. alpine amps are rated at 2 ohms and 14.4V. over rated stuff and seeing as how the amp is seeing 3 ohms instead of 2, your gonna get even less wattage out of the amp.