Needing help with system

[StoopidAlero]

Hopefully Ryan will jump in on this.

Ok, So I have two 12" Powerbass subs with a 800.2 powerbass amp. My headunit is the Jensen UV8. The problem Im having is when I turn on my car, the subs "surge" Like the just make a bass sound with no music playing at all. Usually when I start up my ipod it goes away, but tonight, the screen was going in and out on the indash, and the subs just kept making a bass sound. When the screen finally came on, as I would excellerate, there was a whining sound coming from all the speakers. Im not sure if its the POS headunit, or if its something that could easily be fixed. I had a 1 farad cap on the system and I still had problems with it. I need some help!! thanx

[fielder87]

when i turn on my car i also get a sub pound.just them getting power to them.if yours stays on you got a problem.as for the whining as you accelerate,mabey your power wire is by your audio's and it jumping?i have heard of that before,and to run one on each side of the car.other than that good luck.

[PappaSmurf]

Stoopidalero,
Honestly it sounds as if you are having a ground problem. Maybe one of your grounds have wiggled loose or something. I have had the same thing happen to me. Everythings fine for a while and then all of the sudden, wham. The whine is only when you accelerate is probably a good sign that you need a ground lopp isolator. This is the thing that help me get rid of my whining while accelrating.
Hope this helps.
-Smurf-

[lonnie]

If your gains on the amp are too high, that could cause thump, try adjusting the gains down a few times then starting the car. Sounds like your amp is turning on before the deck, and getting signal before the deck full powers up. Whining is a ground loop problem, and you should route all of your grounds to one point...buying a ground loop isolator could work but isn't guaranteed.

[cherrington17]

ground loop is causing the acceleration problem. so, check all your ground connections, and make sure they are solid. (meaning, pull them off and check throughly)

the sub noise might be a bad RCA connection/signal from your POS headunit. i'm not sure if its bad or not. but start there.

[StoopidAlero]

thanks everyone! I have replaced the RCAs once already. I will definately check the gains today on the amp. And as far as the ground, should I be checking the ground to the headunit, or the amp?

[cherrington17]

both.

headunit will most likely give you the ground loop that'll give you the speaker whine. the amp might be giving you the bass issues.

[StoopidAlero]

Hmm.. So I just went out to try some of those things, and I notice that when I mute the headunit, the subs keep beating to the music?

[surreal_awakening]

My Apine HU in my Jeep doesn't fully mute. It just turns way down. You can still hear the music some. As for the thump, isn't this often a result of not having a delay in the amp turn-on?

[mach3]

Sounds like your problem is a wiring issue. Like most others here have already mentioned, check your ground and also clean the grounding spot so that there are no dirt/dust, or paint.

you should also check all your connections not just the grounding plus pay attention to areas where you might have a pinched wire that could be the main cause.

[Gr1m]

check your grounds all over the car and i would buy a quality RCA and test it before you rerun the wire, if it doesnt change then just leave the old one in because thats not your problem.

[StoopidAlero]

Well when I turn on the car, the headunit turns on, but doesnt power up right away. SO I could see what youre saying surreal.

[lonnie]

Hmm.. So I just went out to try some of those things, and I notice that when I mute the headunit, the subs keep beating to the music?
Well when you say beating to the music that could be anything....Is it beating allot as if it was playing at full volume...Is it beating slightly.....What you want to listen for is if when starting the car you get the thump, or when turning it off. Did you turn the gains all the way down and slowly start working your way back up. With the HU down and the gains down you shouldn't see much on the subs at all. Best to cover all your bases before having to tear into the wiring.

[StoopidAlero]

No, its not very loud. I turned the headunit all the way down, and the bass was still hitting at the equvilent of maybe volume 3. I did the gain thing, and it helped, but there is still the thump when I turn on the car, or turn it off. I really dont think its the grounds just because when i had my old indash in, everything was grounded the same. I just started having the problem when I switched up the system.

[cherrington17]

is the amp... new to your system, but not new.. in its existance?

my component is a decent old one from a friend, and it lacks "soft turn on" to my speakers "pop" everytime i turn the car on.

[StoopidAlero]

The amp is about a year old

[lonnie]

The amp is about a year old
Thats young enough to have the soft on/off but what model is it...just may not have it built in...there is a way around it though.....put a relay on the remote wire that may give you the time needed between ...... I'm starting to wonder if the RCA's are shielded, and if they are shielded if they ground from the HU to the amp?

Maybe run the remote wire on a circuit that is only on when the ignition is turned on...the radio comes on with the key in the ACC position...which would turn the radio on first the with the amp on an ignition circuit the amp would then turn on?

Just throwing some ideas out there!!!

[surreal_awakening]

Well when I turn on the car, the headunit turns on, but doesnt power up right away. SO I could see what youre saying surreal.

I think this may be your thump issue. As I understand things....when you turn on the HU, it sends the audio signal to the amp. If the amp doesn't have soft turn-on, the amp may power up quicker than the HU and it will be on when that audio signal arrives. That initial signal can have a small voltage spike associated with it, which can cause that thump. Soft turn-on eliminates it by delaying the amplifier power-up until after the HU has powered up and sent that initial signal/spike. But if your HU is not powering up right away, the amp could be getting ahead of the HU, even with soft turn-on. I think you can build a module to delay the amp turn-on, but if your HU has recently started taking longer to turn on, then I would say the HU is your real culprit.

[lonnie]

I think this may be your thump issue. As I understand things....when you turn on the HU, it sends the audio signal to the amp. If the amp doesn't have soft turn-on, the amp may power up quicker than the HU and it will be on when that audio signal arrives. That initial signal can have a small voltage spike associated with it, which can cause that thump. Soft turn-on eliminates it by delaying the amplifier power-up until after the HU has powered up and sent that initial signal/spike. But if your HU is not powering up right away, the amp could be getting ahead of the HU, even with soft turn-on. I think you can build a module to delay the amp turn-on, but if your HU has recently started taking longer to turn on, then I would say the HU is your real culprit.This is a real nice way of saying......

Thats young enough to have the soft on/off but what model is it...just may not have it built in...there is a way around it though.....put a relay on the remote wire that may give you the time needed between ...... I'm starting to wonder if the RCA's are shielded, and if they are shielded if they ground from the HU to the amp?

Maybe run the remote wire on a circuit that is only on when the ignition is turned on...the radio comes on with the key in the ACC position...which would turn the radio on first the with the amp on an ignition circuit the amp would then turn on?

Just throwing some ideas out there!!!LOL...here is some other info
http://bcae1.com/images/rca/temporaryrcashieldrepair.html

[lonnie]

Solution found:
http://www.davidnavone.com/cart.asp?24&cat=1

[StoopidAlero]

So youre saying that maybe the gold plated ends of the RCAs might be grounded somewhere? Like behind the headunit. And that would cause thump and possibly the noise coming from the speakers? Im still clueless on why the subs still play (very softly, but its annoying) even when I mute the headunit

[StoopidAlero]

thats pretty cool! Good job! And thanx! I think I might just end up selling this Headunit. It works flawlessly without my amp and subs hooked up. But I just get alot of noise with the rest of the system installed. Plus, I want an indash with the ipod controls and ipod charger.

[lonnie]

So youre saying that maybe the gold plated ends of the RCAs might be grounded somewhere? Like behind the headunit. And that would cause thump and possibly the noise coming from the speakers? Im still clueless on why the subs still play (very softly, but its annoying) even when I mute the headunit
When you say you mute the headunit...I think it is still sending a low signal which is still being amplified. Could be coming from the RCA's, may just be that the amp is being left on just before the head unit goes off...you will have to eliminate them one by one...starting with the easiest and working your way up to the one that is more time consuming....I would try running the remote wire through a relay with a diode on it first.....you could also try putting a capacitor on the remote wire....as far as size you would have to figure that out..but you want it big enough to keep the amp on momentarily...If you don't understand anything I said let me know and maybe I can explain it better....I'm not the best at explanation...sorry!

[surreal_awakening]

This is a real nice way of saying......

LOL...here is some other info
http://bcae1.com/images/rca/temporaryrcashieldrepair.html

LOL yeah, what Lonnie said!

[Ryan from Ohio]

Its the head unit or wiring of it.