Ok, so I just got a new 3000d and a 100.4. My HU only had front/rear, no sub pre-amp output. Question is, if I wire the front/rear to the 100.4, if i Use the channel 1/2 output to the 3000d, will I lose my ability to use the hp/lp settings on 1 and 2 or if I do use the hp/lp will it still send a full signal through the 1/2 output?

Sorry if I am not being very clear..

front / rear from head unit

into 1/2 and 3/4 of the 100.4

1/2 output to 1 on 3000d

will using filter controls on 100.4 impact frequency output on 1/2 output channels?

No, the line-out is always full range -- you'll be fine as long as no filters are active on the HU on the input channels.

awesome thank you! Was afraud I was going to have to exchange my head unit..