pac aoem gm24

I ordered the PAC AOEM-GM24 adapter and installed it and so far everything seems good. I do have a question or two that I can't seem to find any answers for, so maybe someone here can help me. The PAC interface has gain controls for the front and rear RCA jacks that it adds. There's no info on PACs site to tell me how to set the controls properly, and I can't seem to locate any info anywhere else. I do know from playing around with them that it really cranks up the signal/volume when you adjust them. I'm planning on setting my amp to reduce clipping as much as possible and I know the PAC needs to be adjusted properly before I can set my gain on the amp. Anyone know the proper way to do this? Setting them "by ear" isn't an effective and proper way to do this IMO. And secondly, when I set the gain on the amp itself, would I use 4 Ohm in my calculations since thats what the subs are, or use 2 Ohm since thats how I have them wired? And also, do I use what the amp is rated at (400W) or what the birth sheet says (500w)? The set up is in a 2004 Silverado with the Bose system. I added Rockford Fosgate P-400-1 (rated at 400 watts, birthsheet says its closer to 500) Two JL Audio 10W3V3 $ Ohm subs wired to a 2 Ohm load

Setting gain by ear is absolutely appropriate, and in some cases more accurate than using the voltage method. Reading voltage does not tell you if the signal is clipping: listening to a test tone will. You set the gain on your adapter just like you would for an amp. And if you are wiring the subwoofers for a 2-ohm load on the amp, then that is what you "use" as a target impedance. I suggest you try using the test-tome by ear method before you dismiss it. If you need instructions see the Hot Topics forum.Support the12volt.com