2 replies to this topic

[Southy]

Hi guy's had an issue lately with my amp powering my sub which I hope you can help myself out with.
When I used to turned the ignition on, I heard the sub make a large thud as per the amp powering up, but afterwards the sub kept on moving and making a noise and moving to maximum excursion even when no music of any sort was playing.

I did the usual check's first of all, made sure all the power leads and speaker wires were tight and that the ground cable had a nice clean ground yet it still continued.
I've connected the sub upto another good known amp and the sub work's fine so that isn't the problem. I then tried the noise check's as stated on another site where you unplug one side of the RCA cable. Upon removal of the first RCA it still did the same, when I plugged the RCA back in (to what I thought was the correct jack, working in the dark and by touch didn't help) and unplugged the other the noise stopped once powered up.

When I plugged the other jack back in the sub worked fine, albeit rather quieter than before, upon closer inspection I had accidently plugged the RCA lead into the output/Through jack's of the amp. The amp I'm using is a Sony X-plod XM-D500x. I've taken the amp to bit's and nothing looks wrong or out of place to myself, but then again I'm no expert on amps

Do you think the problem is the input female RCA connections on the amp itself and I need to remove/replace these connections and the amp will work fine once again or something more serious is wrong?

Regards
Adam

[chalkie]

Hi guy's had an issue lately with my amp powering my sub which I hope you can help myself out with.
When I used to turned the ignition on, I heard the sub make a large thud as per the amp powering up, but afterwards the sub kept on moving and making a noise and moving to maximum excursion even when no music of any sort was playing.

I did the usual check's first of all, made sure all the power leads and speaker wires were tight and that the ground cable had a nice clean ground yet it still continued.
I've connected the sub upto another good known amp and the sub work's fine so that isn't the problem. I then tried the noise check's as stated on another site where you unplug one side of the RCA cable. Upon removal of the first RCA it still did the same, when I plugged the RCA back in (to what I thought was the correct jack, working in the dark and by touch didn't help) and unplugged the other the noise stopped once powered up.

When I plugged the other jack back in the sub worked fine, albeit rather quieter than before, upon closer inspection I had accidently plugged the RCA lead into the output/Through jack's of the amp. The amp I'm using is a Sony X-plod XM-D500x. I've taken the amp to bit's and nothing looks wrong or out of place to myself, but then again I'm no expert on amps

Have you checked that the wires connecting the amp to the sub are positive to positive negative to negative?
If they are correct make sure your RCA leads are the same from headunit to amp. Ensure the colours match up.

Try turning your amp down on gain and check the difference, it may be too powerful for your sub (happens a lot)
Then pop in a switch. Best thing you can do with a sub and amp. You can then turn it all off separately.
It's easy to do just cut the remote ( blue) wire and put each end on the switch.

Hope you find the fault.

Do you think the problem is the input female RCA connections on the amp itself and I need to remove/replace these connections and the amp will work fine once again or something more serious is wrong?

Regards
Adam

[pbrain]

is the main +12V on the amp wired permanently to the battery?

measure the resistance from the amp's (-) terminal to the battery connector, you want this as close to 0 ohms as possible (certainly less than 1.00 ohm) i killed an expensive DLS CA1000 because of a rusty earthing point (~10 ohms)

turn the gain to minimum on the amp, adjust upwards.

try again with a different RCA leads (measure the leads - resistance from point to point and check insulation resistance ...resistance between centre pin and outer connector)

check the output levels on the head-unit (not too much volume/boost on sub-out)

check connections/resistance on head-unit

...these are just a couple of starting checks.