Amp Not Working - Ground Wire Sparks & Problems

[teegz]

My amp was working fine, until the other day, i disconnected the rear
speakers and left the speaker wires hanging free in the boot cuz I
needed the extra room to put my bike in there. During this time I
listened to my radio from the front speakers (which are not connected
to the amp). Neways, when I went to reattach the rear speakers, I get
a quick low sound pop when I turn on the car to ACC, then no sound
from the rears. The LED is illuminated, the fuze is OK, battery and
remote connections are ok, and the speaker input to the amp is fine.
HOWEVER I noticed that while the radio is on, if I move the tip of the
ground wire that is connected to the car around on a metal surface, I
get sparks and the sound comes thru the speakers for about 1 second,
then fades away but the LED stays illuminated like its properly
grounded.

My theory is that while the speaker wires were hanging free, they may
have come into connect with the metal of the bike??? I don't know....

Any help would be greatly appriciated.

Regards,
Tegan.

[Sanitarium]

I hope you insluated the bare speaker wires while they were hanging
free?
Very posible they shorted to each other or possibly to ground. (I am
assuming you had the wires connected to the amp while they were hanging
free) If thats the case, the amps protection circuitry should have
kicked in, but even with the protection circuitry something could have
fried in the amp.

IMHO its not a very good idea to be
connecting/disconnecting/re-connecting the amps ground while the system
is powered up. Circuits generally dont enjoy the current surges. So,
IMHO you should leave the ground connected while you are trouble
shooting. While youre at it, make sure the ground is solid and not
loose.

I fried a very expensive JBL tweeter once when my speaker ground shorted
to the chassis.

BTW... what kind of amp is it? Some amps behave differently when
protection circuit kicks in.

Garrett

teegz wrote:
>
> My amp was working fine, until the other day, i disconnected the rear
> speakers and left the speaker wires hanging free in the boot cuz I
> needed the extra room to put my bike in there. During this time I
> listened to my radio from the front speakers (which are not connected
> to the amp). Neways, when I went to reattach the rear speakers, I get
> a quick low sound pop when I turn on the car to ACC, then no sound
> from the rears. The LED is illuminated, the fuze is OK, battery and
> remote connections are ok, and the speaker input to the amp is fine.
> HOWEVER I noticed that while the radio is on, if I move the tip of the
> ground wire that is connected to the car around on a metal surface, I
> get sparks and the sound comes thru the speakers for about 1 second,
> then fades away but the LED stays illuminated like its properly
> grounded.
>
> My theory is that while the speaker wires were hanging free, they may
> have come into connect with the metal of the bike??? I don't know....
>
> Any help would be greatly appriciated.
>
> Regards,
> Tegan.

[teegz]

The wires hanging free were not insulated, I didn't think about at the
time...probably a bad idea. The amp is a 250w Boss BA-250. It's still
under warranty - do you think I can take it back in for a refund??

Any hints on why the sound comes through when I move around the ground
wire?

Tegan.

[David Wood]

> The wires hanging free were not insulated, I didn't think about at the
> time...probably a bad idea. The amp is a 250w Boss BA-250. It's still
> under warranty - do you think I can take it back in for a refund??
>
> Any hints on why the sound comes through when I move around the ground
> wire?

There might be some sort of protection circuit kicking in now, as a
result of damage that was already done to the amp by running it without
a proper load.

Regardless of whether or not the wires are insulated, it is never a good
idea to run an amp without a proper load attached to it. Next time you
run without your rears like that, it's best to either disconnect power
to the amp, or make it so that signal isn't being sent to the amp.

[teegz]

OK so is there any way i can fix this prob by myself???? or must i
take it back in2 tha dealer or 2 some sort of fixing person????????

[teegz]

How does one tell if the speaker terminals are shorted? Should I maybe
try replacing the speaker wires that run from the amp to the speakers,
I don't know what effect an overload would have on simple speaker
wires. Also, is it possible it may be the fuse next to the battery on
the battery wire? I've had a look, but it looks ok, although I've
never seen a blown fuse like that one before. The fuse looks like
this:
_____________
| |
|_____________|
|| ||
|| ||
| \ / |
| | | |
| | | |
| | | |
| / \ |
||_________||
| |
|_____________|

Thanks for your help guys,
Tegan.

[David Wood]

> How does one tell if the speaker terminals are shorted?

Just make certain that bare wire isn't touching bare wire, or any metal
in the car other than the speaker terminals.

> Should I maybe
> try replacing the speaker wires that run from the amp to the speakers,
> I don't know what effect an overload would have on simple speaker
> wires.

You could make a temporary, easy to undo run just for kicks. Wouldn't
hurt.

> Also, is it possible it may be the fuse next to the battery on
> the battery wire?

Well, you said that you got your amp to "pop" on from time to time, even
if it was just for a split second.
That suggests that the fuses are fine.

It's probably something internal to the amp, therefore you'll have to
send it in.