Corbin Dallas
Junior Member
Caveat: This is an older school equipment quandary
I recently had some time and became re-interested in car audio again after an 8 year hiatus. Kids will do that. After reading the posts over the last week or so I felt motivated to finish some of the minor things I knew needed addressing in my truck.
Today I was tweaking my system by replacing the rear stock speakers with some old Rockford coaxes I had laying around. They run off the head unit and really do not see much signal as I really love my Focals up front.
I decided to button down the amp under the rear seat (Ext cab Silverado) because the kids have managed to salt, gum, candy and lollipop stick the top of my once beautiful Alpine Expert amp as it precariously sat on the middle hump and slid forward over time.
In doing this, I started to play with the settings on the amp as I noticed my subs getting full range. "That's weird", I thought, so I set the LP switch on the amp and the subs played as they should have and I was happy. I wondered if one of the kids may have inadvertently set it to full range in the past, but figured it was not likely.
As I looked closer, I saw that the amp had a 4v or nom setting (kids also tend to make you forget all the cool things your toys could do when you bought them) and it was set at nom. "That's weird", I thought again as I switched it to 4v because I have 4 volt pre-out on my head unit. Well, when I did, the bass dropped. Say it with me - "That's weird", I thought as I flicked it back to nom because it sounded better.
So I ask, why if my sub gain and fade control on the head unit work fine, would the amp see full range out of those pre-outs? And why would it drop in volume when I switch the amp input to 4 volt?
Alpine CDA-7894
Alpine MRV-F505
I recently had some time and became re-interested in car audio again after an 8 year hiatus. Kids will do that. After reading the posts over the last week or so I felt motivated to finish some of the minor things I knew needed addressing in my truck.
Today I was tweaking my system by replacing the rear stock speakers with some old Rockford coaxes I had laying around. They run off the head unit and really do not see much signal as I really love my Focals up front.
I decided to button down the amp under the rear seat (Ext cab Silverado) because the kids have managed to salt, gum, candy and lollipop stick the top of my once beautiful Alpine Expert amp as it precariously sat on the middle hump and slid forward over time.
In doing this, I started to play with the settings on the amp as I noticed my subs getting full range. "That's weird", I thought, so I set the LP switch on the amp and the subs played as they should have and I was happy. I wondered if one of the kids may have inadvertently set it to full range in the past, but figured it was not likely.
As I looked closer, I saw that the amp had a 4v or nom setting (kids also tend to make you forget all the cool things your toys could do when you bought them) and it was set at nom. "That's weird", I thought again as I switched it to 4v because I have 4 volt pre-out on my head unit. Well, when I did, the bass dropped. Say it with me - "That's weird", I thought as I flicked it back to nom because it sounded better.
So I ask, why if my sub gain and fade control on the head unit work fine, would the amp see full range out of those pre-outs? And why would it drop in volume when I switch the amp input to 4 volt?
Alpine CDA-7894
Alpine MRV-F505