I was curious if anyone could help me....I recently wired up four speaker, a new alpine deck, and an alpine F240 4 channel amp....all works well with the exception of the amp...there is no sound coming from the sub, and when i try to hook up a junk speaker to test the amp again, no sound comes out either...The remote turn on wire is hooked up right, the amp is grounded very well, but yet no sound is getting to the sub....Now, i am using an old RF series 1 10" sub just the test before he buys a couple descent subs, but the sub doesnt kicka at all...I know the sub works, just not with that amp....Even when i hook up just the left or the right side of the RCA and touch the opposing RCA (whichever one is not hooked up) there should atleast be a buzzing sound coming out of the speaker, but still nothing happens...So i think it may be and RCA problem??? I am flippin lost, and have run out of ideas....FYI...the head unit is the alpine 9853 model, so i dont know if i have to do anything with that other than put subwoofer on and that stuff....please responds, it would be greatly appreciated. Thanks
Norwegian passing by.
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First of all, you've checked the LED's on the amp, and at least one is lit up, right?
If not, check the fuse(s) Ok?
Check if you've bridged channel 3 & 4 for subwoofer use (Because of the subsonic filter at 15 Hz) , and if you've connected to the appropriate RCA intakes.
Still dead?
I expect you to have a multimeter / voltmeter at hand here. Now you measure the voltage (AC) on the RCA-cable while the head unit is on (What you really do here is to check if there is a sinus-signal there, it's therefore you need to check the alternating voltage). You should have changes in the voltage measured that's in harmony with the music. If not, check at the head units RCA connection.
If you do get a signal, replace the cable, and while you're at it, look for reasons why the cable got broken, burnt spots, hard bends, or most likely, a place where the cable got squeezed.
If you still got no signal... Don't know which RCA's you've used, but i choose to believe you've used those that's marked with "subwoofer".
I'm not familiar with the Alpine 9853, but i also suggest checking for a on-off control for subwoofer in the menu.
The speakers you've tested with, they ARE 2-4 ohms, right?