Welcome to Just Commodores, a site specifically designed for all people who share the same passion as yourself.

New Posts Contact us

Just Commodores Forum Community

It takes just a moment to join our fantastic community

Register

turning off power

commyvx

New Member
Joined
Mar 13, 2006
Messages
40
Reaction score
0
Points
0
Location
brisbane
Members Ride
VX Executive S2 V6
when i turn my car off or turn off the head unit the subs make a thud noise why does this happen?
 

shaggerz

New Member
Joined
Jun 29, 2005
Messages
1,626
Reaction score
45
Points
0
Age
38
Location
Victoria Point, Brisbane
Members Ride
2004 VY2 SV8 A4
when the power to the head unit is cut, either by you switching the head unit off or the car, there is a voltage spike produced that is making its way through your RCA outs to the sub amp.

Ordinarily, what SHOULD happen is that when the power to the head unit disappears, the sub amp remote turn on voltage should be the first to drop to zero, causing the sub amp to switch itself off before that little spike makes its way to the inputs.

Most decent car audio amps also have a subsonic filter built in that removes any voltages that dont oscillate above about 10Hz. This covers pretty much any DC spike that may present itself at the inputs for any reason.

Diagnosis can be made from there.
 
Top