Installed an Alpine head unit, But getting turn 0n thump from factyory subamp??

New Ford Guy · 08-20-2006, 08:46 AM

Hi Members, I installed a Alpine 9835 head unit in my 2003 Eddie Bauier with the proper Metra wiring harness with the factory sub input. But i'm getting turn on thump from the factory subwoofer amp. It Only thumps when turned ON not when turned off. I tried manually delaying the amp turn on with the blue amp turn on wire....we still had the THUMP?? So I unplugged the RCA's from the head unit to the subwoofer connection(to check for ground loop)...we still had Thump?? Anybody else had this problem? Anybody have a Solution?
I Have the Audiophile factory system with factory Sub.(only the sub has the factory Amp). I just need to get rid of the THUMP !!!

Thanks in advance...New Ford Guy

*snocross1985* · 08-20-2006, 10:07 AM

I used to have the same problem when I had my old system in my truck, have no idea what caused it. Gonna be putting a new system in my truck and am curious as to what causes the turn on thump.

New Ford Guy · 08-20-2006, 12:26 PM

Anybody have any answers????

*Brandons* · 08-20-2006, 01:20 PM

I dont think its anything to be concerned about, start a computer on with the speakers on and you usually get a thump. Might just be from turning on, first bit of power that goes to it, did you try turning it on without the head unit on and see if it still thumps?

DOZIER · 08-20-2006, 05:03 PM

I had the problem along time ago and I was told that the preamptive outputs were bad in my head unit. I replaced the head unit and problem solved.

nvrenufedge · 08-20-2006, 07:56 PM

If you've already tried unplugging the RCA's, the only thing I can come up with is there is something wrong with the amp.

ajr2000 · 08-20-2006, 10:13 PM

In pro audio, the thump, or in the case of pro-audio, pop, is caused by the amp being on before the audio source, in this case the headunit.

In this case I would say your amp is screwed up however.

*Brandons* · 08-20-2006, 10:15 PM

Id be curious to know if it happens to thump if you just turn the amp on manually (jump the amp on wire?).

davesexplorer · 08-21-2006, 05:56 PM

I'd venture a guess that it comes from the "meshing" of sorts between the aftermarket head unit giving the factory amp turn on power, whilst the factory amp is already turned on on. The remote signal delay from the Alpine would be fine for aftermarket amps designed for it, but if what im thinkin is happening is that the factory amp is on before that.

08-20-2006, 08:46 AM	#1
New Ford Guy Wannabe Elite Explorer Moncton, New Brunswick, Canada 2003 Eddie Bauier Join Date: Aug 2006 Posts: 2 Vehicle Specs (Original Poster)	Installed an Alpine head unit, But getting turn 0n thump from factyory subamp?? Hi Members, I installed a Alpine 9835 head unit in my 2003 Eddie Bauier with the proper Metra wiring harness with the factory sub input. But i'm getting turn on thump from the factory subwoofer amp. It Only thumps when turned ON not when turned off. I tried manually delaying the amp turn on with the blue amp turn on wire....we still had the THUMP?? So I unplugged the RCA's from the head unit to the subwoofer connection(to check for ground loop)...we still had Thump?? Anybody else had this problem? Anybody have a Solution? I Have the Audiophile factory system with factory Sub.(only the sub has the factory Amp). I just need to get rid of the THUMP !!! Thanks in advance...New Ford Guy Last edited by New Ford Guy; 08-20-2006 at 10:14 AM. Reason: Added Info

08-20-2006, 10:07 AM	#2
snocross1985 Explorer-less South Hampton, NH 2002 Sentra SE-R Spec V Join Date: Mar 2003 Posts: 2,728 Vehicle Specs	I used to have the same problem when I had my old system in my truck, have no idea what caused it. Gonna be putting a new system in my truck and am curious as to what causes the turn on thump. __________________ Scott My Mug

08-20-2006, 01:20 PM	#4
Brandons Elite Explorer Ontario, Canada 06 F150 SC 5.4 Join Date: May 2002 Posts: 2,626 Vehicle Specs	I dont think its anything to be concerned about, start a computer on with the speakers on and you usually get a thump. Might just be from turning on, first bit of power that goes to it, did you try turning it on without the head unit on and see if it still thumps? __________________ 2006 F150 XLT Supercrew 5.4L 1994 XLT 4.0L 1997 XL 4.0L

08-20-2006, 05:03 PM	#5
DOZIER Wannabe Elite Explorer Fultondale, Alabama 2001 explorer sport Join Date: Jun 2005 Posts: 1,026 Vehicle Specs	I had the problem along time ago and I was told that the preamptive outputs were bad in my head unit. I replaced the head unit and problem solved. __________________ If you can't convince them...Confuse them.

08-20-2006, 07:56 PM	#6
nvrenufedge Wannabe Elite Explorer Boise, ID '05 XLT Join Date: Jul 2006 Posts: 178 Vehicle Specs	If you've already tried unplugging the RCA's, the only thing I can come up with is there is something wrong with the amp. __________________ The Family Hauler Alpine INA-W900 w/navigation Yakima hitch-mount bike rack More to come....

08-20-2006, 12:26 PM	#3
New Ford Guy Wannabe Elite Explorer Moncton, New Brunswick, Canada 2003 Eddie Bauier Join Date: Aug 2006 Posts: 2 Vehicle Specs (Original Poster)	Anybody have any answers????

08-20-2006, 10:13 PM	#7
ajr2000 Wannabe Elite Explorer Trumbull, CT 93 XLT Join Date: Mar 2006 Posts: 184 Vehicle Specs	In pro audio, the thump, or in the case of pro-audio, pop, is caused by the amp being on before the audio source, in this case the headunit. In this case I would say your amp is screwed up however. __________________ -Andy 93 Ford Explorer XLT, 4.0L OHV - Conical filter intake, custom intake tube, BBK 66mm Throttle body, Flowmaster 40 delta exhaust, Aluminum dash bezel, All Jensen sound system, throttle cable mod, Clear Corners My Cardomain

08-20-2006, 10:15 PM	#8
Brandons Elite Explorer Ontario, Canada 06 F150 SC 5.4 Join Date: May 2002 Posts: 2,626 Vehicle Specs	Id be curious to know if it happens to thump if you just turn the amp on manually (jump the amp on wire?). __________________ 2006 F150 XLT Supercrew 5.4L 1994 XLT 4.0L 1997 XL 4.0L

08-21-2006, 05:56 PM	#9
davesexplorer Wannabe Elite Explorer Central PA 2001 F350 7.3 Join Date: Mar 2001 Posts: 2,808 Vehicle Specs	I'd venture a guess that it comes from the "meshing" of sorts between the aftermarket head unit giving the factory amp turn on power, whilst the factory amp is already turned on on. The remote signal delay from the Alpine would be fine for aftermarket amps designed for it, but if what im thinkin is happening is that the factory amp is on before that. __________________ 2001 F350 Extended Cab Long Bed Lariat 7.3 Powerstroke 4x4 1999 Mustang GT 5spd vert