Sub Thumps when I turn radio On/OFF

[toicy4ya]

Sup guys,

First off let me say that I did a search prior to posting and although I did find several post's, some were old, some weren't relative and on some I had already done what what the responders of those post's recommended. This isnt anything new but I own a Alphasonik PMZ12005A 1200W amp and every time I powere on/off the radio the sub makes this annoying thump. I know it doesn't mess anything up, but it's really annoying. I tried regrounding both my Pioneer head unit as well as my amp, Played around with the RCA's and nothing. I understand they sell some kind of filter but dont know if it's really worth purchasing or where to buy it. Can you guys give me some helpful advice, it would be greatly appreciated.

Thanks

 

[95blackGsTurbo]

Should have posted this in Appearance/Interior/Exterior. Would have gotten a lot more help in that forum. Every system I have ever had did that when I turned the radio off/on as well. I just assumed it was normal from a surge from it turning on/off.

 

[98RedDragon]

that can be caused by having any speaker wire goin to the subs ran next to a power cable, for instance the one coming from your battery, or power block.

 

[carl5463729]

My system does the same thing. I'm not sure if this is true but two people told me that i need to run the power on/off wire that goes to the amp off of the power wire in the radio. i have mine hooked up to a fuse which goes on whenever i turn the key. if you have yours wired like i do, then that might be it. I'm getting rid of my system soon so i don't really care.

 

[Listen2myBASS]

might wanna check your ground wire

 

[97GsXfreak]

My car does the same thing and my ground wire is all good. It's funny when people jump because of it though

 

[toicy4ya]

My car does the same thing and my ground wire is all good. It's funny when people jump because of it though

, yea same here. Like I mentioned I checked and even regrounded both my Pioneer head unit and amp, in addition played around with the rca's and nothing. I'm stumped.

I remember reading somewhere that they sell a On/Off filter for this exact very thing, just dont recall where.

 

[buugiewuugie]

Every system in EVERY car I have ever had has done this. I think how loud the thump is really depends how much power your amp is pushing.

I may be wrong but think about it. When you plug any speaker in, for instance computer speakers.. they thump when you plug them in. It may, like 95blackGsTurbo said, just be a power surge.

 

[DSMcamaro]

I would check ALL your wires. I've had many differnt system and I did have this same problem once, but I cant exactly remember what I did to fix it, but i know it has something to do with the wires. If you have more than one set or RCA outputs on your head unit, I would try differnt ones. (I also have a pioneer head unit, so it might be a pioneer problem) Also, If your RCA wires are ran right next to your power cable, you might wanna run them a different way so they are father apart. Make sure your speaker wire going from the amp to the subs isnt messed up anywhere or touching another wire.

 

[fr33b1rth]

i bet it's just because the 5th channel is a cheap amp. most sub amps will turn on the amp's power supply, then connect the speakers, and the exaxt reverse when turning off. does the amp have a protect light? if so, when you turn on the head unit see if the protect light comes on, then the power light or if the power light just comes on. if you don't have a protect light, turn everything off and all the way down. get your head right next to the amp and turn on your head unit from your remote (or have a buddy do it) and see if you hear a click when the amp turns on, then another click. if not, your amp does not have a anti-thump circuit.

 

[timm98gst]

yup just like that guy said, cheap amps will do that - better amps will have a delayed turn on circuit - and make sure your amp remote wire is hooked up to the power antenna wire on the back of your head unit

 

[toicy4ya]

Sup guys,

I just got this from one of the other forums. I'll be giving it a shot this weekend.

http://www.partsexpress.com/resources/relays.html

 

[snyper1982]

Im not exactly sure why you think you need a relay? All a relay is like a swith that automaticaly turns on when it sees power. Your speakers are still gonna thump. I have never, ever had this problem, because I have always used more expensive amps, such as zapco, JL, and older fosgate stuff. The cause is your amp, plain and simple.

 

[bmason]

all it is is your amp turning on and off if u watch your amp when this happons most likely it will happon when your light turns on every amp should do this it natural if you have your voulume all the way down u might not hear it tho

 

[mavisky]

I've never ever had this problem with any stereo I've ever installed. So people saying its normal are wrong. I've had no issues with everything from $50 walmart amps to my $600+ Memphis.

Where is your 5 volt signal to the amp coming from? Is it coming from the blue remote wire on the back of the deck?

Are your rca's running down the same side of the vehicle as your power?

How long is the ground wire on your car?

 

[Tx97GSX]

I have had a couple of different systems in my car and I have never had that problem with my sub. I would suggest like someone before me said and to move your RCA cables away from your power cable.

 

[sk8shorty01]

running the RCAs near the power usually isnt whats causing that thump though... its the speaker wires, because there is crosstalk between the wires... running the RCAs on the same side as the power wire will give you road noise (a humming that goes right along with your rpms)

 

[snyper1982]

Easy test to see if your amp is the culprit. Unplug the RCA's and power the system up and down. If the sound goes away, then it isnt your amp. If it is still there you could try pulling the amp out and testing it that way. I still think it is your amp. Most amps have a delay built in. I know with my zapco it will take like 2 seconds after the deck is powered up to actually start outputting sound.

 

[bmason]

ok i garentee this is the problem but its a big one

its your head unit why you ask?

basicly your headunit plays music and sends it threw the rcas before the remote wire turns on

i garentee this is your problem and the only soultion is to get a new head unit

 

[snyper1982]

ok i garentee this is the problem but its a big one

its your head unit why you ask?

basicly your headunit plays music and sends it threw the rcas before the remote wire turns on

i garentee this is your problem and the only soultion is to get a new head unit

Yeah , well he can EASILY test it by doing what I said. Funny, I can GAURANTEE that I can use his deck on my zapco, and it would NOT do it. Like I said most amps include delay circuitry to delay the amps power out put until the amp is completely powered up, and you dont get the turn on/off thump. My guess is amp still. If you are really adament about fixing it you could build a delay circuit to turn on with your amp, and run your speaker wires to it, then to your speakers, gaurantee that would fix it.

 

[bmason]

Yeah , well he can EASILY test it by doing what I said. Funny, I can GAURANTEE that I can use his deck on my zapco, and it would NOT do it. Like I said most amps include delay circuitry to delay the amps power out put until the amp is completely powered up, and you dont get the turn on/off thump. My guess is amp still. If you are really adament about fixing it you could build a delay circuit to turn on with your amp, and run your speaker wires to it, then to your speakers, gaurantee that would fix it.

so basicly your saying if he gets an amp that stops his head unit by doing that it will fix the problem. and the problem still remains his headunit.

 

[snyper1982]

No, basically I am saying it is his amp sending signal to the speakers before the amp is fully powered up. Some amps have a delay circuit on the output stage, which in effect eliminates the turn on/off thump, and some do not, and there is the problem. I doubt it is his HU. Like I said, he can easily test it by powering up his amp with the rca's unplugged. If he still gets the thump it isnt the HU.

 

[turbo_talon08]

check your ohm load or your gain might be set too high. It could also be a short in the rca's along with a million other things. I would just recommend taking it to a shop with certified installers, that way you know its going to be right and if its not they will work on it untill it is right.