Strange subwoofer issue in car

[po10cy]

Howsit guys

So the other day I installed a amp in my car, power cable is all hooked up fine, amp is grounded to the chasis of the car, i have my amp hooked up to the head unit with the on off cable and the av cables (dunno if thats the right word).

and the only speakers running off the amp is my sub, the others are powered by the head unit. Now for about a week it was working perfectly, until recently the sound from the sub would stop being the music and a "tick...tick...tick" can be heard from the sub. Then if i put off the frontloader, leave it off, the next morning ill put it on again and suddenly the sub is working fine again. All cables are connected fine, i checked it all. Its very strange, this morning the sub would "fade" on and off while playing songs. I doubt its the sub at all, my guess something with the amp, maybe power?

Some more info, the amp only has right and left speaker output, i have the front speakers connected to the left speakers output on the headunit, and the sub is connected to the right speaker output on the amp.

edit: oh and its a 150watt amp.

[hamin_aus]

Make/model of amp and power rating of sub please

Sounds like your amp might be cutting power to the sub. Check for flashing lights on the amp when this happens.

Why are you running a sub with a small amp like that anyway?

[SykomantiS]

Howsit guys

So the other day I installed a amp in my car, power cable is all hooked up fine, amp is grounded to the chasis of the car, i have my amp hooked up to the head unit with the on off cable and the av cables (dunno if thats the right word).

and the only speakers running off the amp is my sub, the others are powered by the head unit. Now for about a week it was working perfectly, until recently the sound from the sub would stop being the music and a "tick...tick...tick" can be heard from the sub. Then if i put off the frontloader, leave it off, the next morning ill put it on again and suddenly the sub is working fine again. All cables are connected fine, i checked it all. Its very strange, this morning the sub would "fade" on and off while playing songs. I doubt its the sub at all, my guess something with the amp, maybe power?

Some more info, the amp only has right and left speaker output, i have the front speakers connected to the left speakers output on the headunit, and the sub is connected to the right speaker output on the amp.

edit: oh and its a 150watt amp.

150? Sounds extremely low. Don't you mean 1500? If it is indeed then a power issue, can the amp support a bridge? Try bridging the sub then. What is the sub's power rating compared to the amp? And is it new or second-hand? Might be a coil issue on the sub (but I'm guessing here- don't quote me on that)

[muffinman]

"tick...tick...tick" can be heard from the sub.

That happened to me and I was told by "professionals" it was the coil.

[hamin_aus]

That happened to me and I was told by "professionals" it was the coil.

If it was the coil in this case, the sub and amp would not start working again after the amp had some time to cool down.

[muffinman]

If it was the coil in this case, the sub and amp would not start working again after the amp had some time to cool down.

Mine did exactly the same, but after 2-3 days of coming on and then dying again, it eventually died completely.

[po10cy]

its strange tho the sub was working fine with no amp, just being powered by the headunit, so should i tune the amp, at the mo its sitting on 0.2v and can go up to 2v, should i make that higher?

oh and its a 150watt rampage amp, the sub ive been running for about 1.5years off the headunit with no issues.

[Firestrm_ZA]

its strange tho the sub was working fine with no amp, just being powered by the headunit, so should i tune the amp, at the mo its sitting on 0.2v and can go up to 2v, should i make that higher?

oh and its a 150watt rampage amp, the sub ive been running for about 1.5years off the headunit with no issues.

now how the f... did you manage that? theres no ways a sub can run off just the head unit unless its a tiny one like a 8"

[maxxis]

Im amazed that the sub actually did anything being run from the HU.

What HU are you running?

Does it have RCA outputs?

From the sound of it the amp is going into protection but that is not likely with the gains being on 0.2v like it is.

Try adjusting the gain to the middle position ie 50% or 1V (doesnt quite make sense)

In the end it sounds like the amp is not wired correctly.

What power cables do you use?

[po10cy]

Im amazed that the sub actually did anything being run from the HU.

What HU are you running?

Does it have RCA outputs?

From the sound of it the amp is going into protection but that is not likely with the gains being on 0.2v like it is.

Try adjusting the gain to the middle position ie 50% or 1V (doesnt quite make sense)

In the end it sounds like the amp is not wired correctly.

What power cables do you use?

i have a wharfedale 54w head unit, plays mp3's and has a port on the front face for a usb stick. How i used to run it is that the front speakers and 6x9's ran on the front speaker output and the sub on the rear, then i faded to the rear so the sub would be a louder volume and actually audible.

yes it does have RCA outputs, thats how i have the amp connected to the head unit.

I have a thick red power cable running from the battery to the amp, it came with one of those amplifier wiring kits. Surely if it wasnt wired correctly nothing would work tho, but it was working fine for a while, only recently started to give this issue.

my wiring is the thick red power cable to the amp, the blue remote on off connected to the head unit, the rca cables to the head unit and then my sub is hooked up to the amp by the right speaker output. and the brown ground cable is hooked up to the chasis of my car by being skrewed in underneath a bolt.

Ill see what adjusting the amp will do to help. thanks

edit: its a 12" sub i have running.

[maxxis]

I take it the HU only has front and rear RCA outputs so what you should do is the following

The rear RCAs should send signal to the sub amp. The front speakers should remain on the HU and be connected to the front left and front right speaker wires.

Never connect more than one speaker per channel on the HU as this will cause the impedance to either jump to 2ohm or fall to 8ohm. The HU can most likely handle 8Ohm but 2Ohm will cause some serious overheating issues.

By using left and right like you are you completely lose stereo on the system which is a bad thing as it will affect sound quality.

Connect the 6x9s to the rear channels of the deck and if you are lucky the deck might support it this way as well as the amp. No sure about this one. I have never done something like this.

For now remove the 6x9s from the HU and wire the HU up correctly. Adjust the amp and see what happens.

[po10cy]

so should i only have one rca cable attached for the channel i want to send? at the moment i have both black and red rca's connected and running to the amp, i have tried using just the rca cable for the particularly channel the sub is run on but the problem with the sub switching off every so often still occured.

I will do as you suggest with the wiring, ill first get the front speakers and amp hooked up like you said and test and only then see if 6x9's will work aswell, but i doubt it would if the amp is taking rear channel.

thanks alot!

[maxxis]

Just confirmed that the HU should keep the speaker channels active on the HU even if RCAs are connected.

Its not the "best" thing to do but it will work.

HU -> Front speakers on correct channels
HU -> Rear speakers on correct channels
HU -> Amp -> Sub vir RCA rear outs on the HU.

[maxxis]

Is this a 2 or 4 channel amp?

If its 2 channel you only need to connect the RCAs for the channels you need.

[IcePick88]

Dude! 150W amp?? What is the wattage of the sub? And running the sub directly on your HU might have caused the poor internal to be damaged!

This is not cosure. Go out and buy a 1200 or 1500W 4 channel amp.

Do this:

Connect one 6x9 to the one channel.
Connect the other 6x9 to the other channel.

That leaves you with two spare channels. If you have a dual voice coil sub, then yeah!
Connect the two coils to the channels of the sub.

If you have a singal voice coil sub, then bridge the two spare channels and connect the sub to them.

Then on the amp, set the high pass filter to on for the two channels that the 6x9's are connected.
Set the low pass filter to on for the two channels that the sub is connected.

When you connect the sub only to the amp and the 6x9's to the HU, your sub will overpower your 6x9's. Connecting them to the amp, gives you more oomph out of your 6x9's and they are not overpowered by the sub.

Edit: If your HU has a dedicated "sub out" like mine, then run the RCA from that to the amp's connectors for the sub.

[po10cy]

Just confirmed that the HU should keep the speaker channels active on the HU even if RCAs are connected.

Its not the "best" thing to do but it will work.

HU -> Front speakers on correct channels
HU -> Rear speakers on correct channels
HU -> Amp -> Sub vir RCA rear outs on the HU.

ok cool thanks alot for the help. good thing its wknd, leaves me with a project to do for 2mo hehe

[SykomantiS]

On the head unit: If it's the same as mine, (and from the description I'm guessing it is) Then it should have 4*45W channels plus two rca out. Best thing to do is like maxxis said. One speaker per channel, this means the two front speakers on the left and right front channels, the 6x9's on the left and right rear channels. This leaves the two rca's to be connected to the amp. Now, it would be good to know if you can bridge the amp (I'm not sure if all amp's support bridging). This basically means that each rca output from the hu goes to one rca input on the amp. But, you'll see each channel output on the amp will have a + and - connector. to bridge the sub, connect one wire coming from the sub to the left channel + on the amp and the other wire coming from the sub to the - connector on the right channel of the amp. (Someone just follow my reasoning here, I confuse myself sometimes ) And do not short out the rmaining left channel - and the right channel +.

Usually the +/- connectors I'm talking about will be situated next to each other in a row like +- +- each one obviously a channel, and you have to use the two outermost connectors. ie + most left along with the - most right.

[po10cy]

ok cool thanks ill give that a go aswell, didnt know you could do that

[SykomantiS]

Added pic to my previous post

Just check, before you give that a go, that the amp is capable of bridging. Otherwise I would not want to be you if you try that...

[Hex_Rated]

Dude! 150W amp?? What is the wattage of the sub? And running the sub directly on your HU might have caused the poor internal to be damaged!

This is not cosure. Go out and buy a 1200 or 1500W 4 channel amp.

It depends if that 150W is the RMS rating. 150W RMS is conservatively about 500W+ PMPO. Some unscrupulous manufacturers will sell 150W RMS amps as 1000W+ PMPO amps. What they don't tell you is the distortion at 1000W is terrible and the amp will only be able to handle that power output for a split second before it sounds like crap.

150W is a little low but for a 10" or 8" sub it should be fine (as long as the rating is indeed RMS).

Never ever buy amps based on their PMPO ratings.

[po10cy]

ok i seemed to have solved the issue, thanks to everyone for the help.

what i did was:

1. rewired the front speakers in the doors to be left channel and right channel respectively for the front speaker channels.

2. Taken out the 6x9's until i can get a decent mounting for them as the one i had wobbles 2 much when i drive over a certain series of speedbumps near the beach, i dont want anything to get damaged.

3. Checked all the wiring to make sure they are secure and no wires are exposed.

4. bridged the sub, so its connected to the + on the left channel output and the - on the right channel output of the amp.

5. moved the grounding cable from the amp to another position on my cars chassis as the last one had a bit 2 much silicone around the bolt it was connected to.

seems sorted now. Thanks guys.

[maxxis]

Glad to hear you got it sorted.

For a proper ground connection sand down the area around the log where the ground connects the chassis.

I did the following

[po10cy]

aaah i see, ok ill give that a go tonight just to make sure its grounded 100%.

[SBSP]

Edit
Never mind i only noticed after the post there was a second page