alpine cda9807 and crossfire ct2160

[philnutz1]

hows it going, i recently purchased a used alpine cda 9807 and it works great, but does anyone know if there is a sub crossover on this unit, it seems to be playing full range even with the bass control set a 60 hz. also on the crossfire, which i have running a 12 inch sub off the sub outs on the 9807 only plays well if one of the rca plugs is unplugged from it. if i plug in both rca's output drops signifigently. Any ideas on what things to check?

[Perry Babin]

Have you checked the shield ground on your head unit?

[philnutz1]

no i have not checked those, how do i go about doing that?

[philnutz1]

and got a 0.5 reading

[Perry Babin]

Did you try connecting the woofer to one channel at a time to see if it would play normally with both RCAs plugged in?

[philnutz1]

but will have to wait until tommorow at work, will let you know results. Thanks for the help. Will also throw this in, when i first start the car the sub thumbs twice like turn on thumb, even when the subwooer control is off. Would be interest to know if there is a way to test all my grounds?

[Perry Babin]

If you think the ground is open, you can use your multimeter set to ohms. Place the black probe on a known good ground and the red probe on the ground terminal of the piece of equipment.

If you think the ground is insufficient, do the same but set the meter to DC volts. Drive the equipment (generally an amplifier) to high power and monitor the DC voltage. Ideally it should never be more than a few thousandths of a volt. If it's more, you need to reduce the resistance in the wiring between the amp and the ground point.

[philnutz1]

tried to hook it up stereo off the right channel, same problem, tried left channel same problem.

[Perry Babin]

Can you post a photo of the inside of the amp?

Do you have an oscilloscope?

[philnutz1]

yes i can post a photo and no i dont think i have an o scope, will post what i have tonight