Did I just break my amp??

Neodudeman

Neodudeman

Audiophyte
So I have this 800 Watt 12V amp, and I finally got it working for the left channel on a single mono speaker.

Since it was working for the left channel, I decided to go ahead and splice in the right channel along with the left channel, since it was just one speaker.

Unfortunately I switched the right channel's polarities when I connected it in parallel with the left channel:

RO+ to LO-
and
LO+ to RO-

but and before I realized it, I had turned it on with a different sound source. The speaker made a little bit of garbled sound, but I thought it was the sound source, so I tried changing sources to a stronger one; but then it made no sound at all...

And now it doesn't produce any sound at all :( even when it's on the left channel only.

Did I break my amp??
 
M

MatthewB.

Audioholic General
Most likely all you did was just blow your fuse. when you crossed polarities. It is very cheap and easy fix. Just take off the cover (after you unlplug the amp-gotta get that warning out there) then check all the fuses, you mave blown more than one so check them all. Take the blown fuses to Radio shack and buy replacements (normally a buck or two) and place the new fuses back in and you should be good to go.
 
Neodudeman

Neodudeman

Audiophyte
I didn't see any extra fuse in there. D:

But I'm no AMP expert, and maybe they use a different fuse??

Here are some photos of inside of my AMP. Maybe you can identify a fuse that I couldn't???:






 
H

highfigh

Seriously, I have no life.
So I have this 800 Watt 12V amp, and I finally got it working for the left channel on a single mono speaker.

Since it was working for the left channel, I decided to go ahead and splice in the right channel along with the left channel, since it was just one speaker.

Unfortunately I switched the right channel's polarities when I connected it in parallel with the left channel:

RO+ to LO-
and
LO+ to RO-

but and before I realized it, I had turned it on with a different sound source. The speaker made a little bit of garbled sound, but I thought it was the sound source, so I tried changing sources to a stronger one; but then it made no sound at all...

And now it doesn't produce any sound at all :( even when it's on the left channel only.

Did I break my amp??
Most car amps are set up to be wired L+ and R- when bridgng and the other terminals aren't used, especially if you have a switch that puts it in bridged mode. You don't want to use the other terminals for anything when it's bridged.
 
TLS Guy

TLS Guy

Audioholic Jedi
So I have this 800 Watt 12V amp, and I finally got it working for the left channel on a single mono speaker.

Since it was working for the left channel, I decided to go ahead and splice in the right channel along with the left channel, since it was just one speaker.

Unfortunately I switched the right channel's polarities when I connected it in parallel with the left channel:

RO+ to LO-
and
LO+ to RO-

but and before I realized it, I had turned it on with a different sound source. The speaker made a little bit of garbled sound, but I thought it was the sound source, so I tried changing sources to a stronger one; but then it made no sound at all...

And now it doesn't produce any sound at all :( even when it's on the left channel only.

Did I break my amp??
That always instantly blows the output stages of both amps. The amp now needs costly repairs or recycling, unless you are lucky enough for the fuses to blow before the output transistors. However you just about never get that lucky when you do that. You have likely learned an expensive lesson.
 
M

MatthewB.

Audioholic General
Sorry ddnt realize you were talking about a car amp, whole other dinosaur there, sorry I can't help.
 
TLS Guy

TLS Guy

Audioholic Jedi
Sorry ddnt realize you were talking about a car amp, whole other dinosaur there, sorry I can't help.
By the way you can not connect the output of any amps together like that, even if they are the correct polarity.
 
majorloser

majorloser

Moderator
I don't know if it's just the picture or dirt. But it looks like there's a film all over everything. Almost like a blown cap or toasted output transistor.

I would agree with TSL's greater experience. I think it's a write off. :(
 
Alex2507

Alex2507

Audioholic Slumlord
I'm curious as to why the output transistors are said to be expensive. I bought four of them for a rec'r @ ~ $5 a piece. I haven't de-soldered the old ones to check them out but that's not expensive by any stretch. Of course I don't know that that is my fix but that's beside the point.
 
TLS Guy

TLS Guy

Audioholic Jedi
I'm curious as to why the output transistors are said to be expensive. I bought four of them for a rec'r @ ~ $5 a piece. I haven't de-soldered the old ones to check them out but that's not expensive by any stretch. Of course I don't know that that is my fix but that's beside the point.
It will likely go beyond the power transistors. More often than not it involves the drivers, diodes and often resistors. It is often a challenge to find where the damage stops. Parts are cheap, finding out which parts have to be replaced, is what you have to be prepared to pay for.
 
H

highfigh

Seriously, I have no life.
So I have this 800 Watt 12V amp, and I finally got it working for the left channel on a single mono speaker.

Since it was working for the left channel, I decided to go ahead and splice in the right channel along with the left channel, since it was just one speaker.

Unfortunately I switched the right channel's polarities when I connected it in parallel with the left channel:

RO+ to LO-
and
LO+ to RO-

but and before I realized it, I had turned it on with a different sound source. The speaker made a little bit of garbled sound, but I thought it was the sound source, so I tried changing sources to a stronger one; but then it made no sound at all...

And now it doesn't produce any sound at all :( even when it's on the left channel only.

Did I break my amp??
I don't know what brand that amp is but the output device shown isn't going to put out enough for the amp to be considered a real 800W amp. Car audio companies are notorious for overrating their power specs and that's why WLS and JBF ratings exist. WLS stands for 'When Lightning Strikes' and JBF stands for 'Just Before Fire'.

As a car amp, the fuses should all be accessible without dis-assembly. If you connect speakers to it in a stereo configuration, if it doesn't work, its outputs are toast. You could try to replace them but as TLS said, it's possible that more parts went away than just those. However, it's also possible that your power supply isn't capable of delivering the needed voltage and current the amp demands, especially when the outputs fried. If you had it connected to a car battery, this point is moot. If it was a 12V low current supply, it may have saved your bacon.

MCM may have the outputs in stock and they're generally not terribly expensive but again, not knowing what make and model of amp you have, I can't tell.
 
Lordoftherings

Lordoftherings

Banned
So I have this 800 Watt 12V amp, and I finally got it working for the left channel on a single mono speaker.

Since it was working for the left channel, I decided to go ahead and splice in the right channel along with the left channel, since it was just one speaker.

Unfortunately I switched the right channel's polarities when I connected it in parallel with the left channel:

RO+ to LO-
and
LO+ to RO-

but and before I realized it, I had turned it on with a different sound source. The speaker made a little bit of garbled sound, but I thought it was the sound source, so I tried changing sources to a stronger one; but then it made no sound at all...

And now it doesn't produce any sound at all :( even when it's on the left channel only.

Did I break my amp??
I did the exact same thing than you did, with my truck's 4-channel power amp,
trying to bridge two channels for my truck's subwoofer.
My amp is toasted, caput. I now only have two channels working on it.
If I want four, I need a new additional car amp.
I've been at all the car audio expert service centers; same answer, "you need a new amp sir". :(
And I paid $800 for that amp, Ouch!

Sorry man,
Bob
 
Last edited:
Neodudeman

Neodudeman

Audiophyte
Thanks a lot for taking the time for audio ignorant like me. :)

You guys have been very helpful, and I really appreciate it.

Ya, it seems like the amp really is broken; which is a complete shame, cause it's been sitting in a box for two months because i didn't realize that the ACC wire was supposed to be High with 12v until yesterday :eek:, and had literally Just gotten it working, lol.

Oh well, so it goes.

Ya, probably the only viable solution would be to test each individual part for damage. The only one I would not be replacing is the chip itself; and I wouldn't know how to test for damage anyway.

I pretty much did everything wrong with this amp, but it certainly was a lesson to be had! I guess I was a bit too overconfident in my abilities as an electrician.

Thanks again everyone! I'll be sure to 'Thank' you each properly.
 
Lordoftherings

Lordoftherings

Banned
Thanks a lot for taking the time for audio ignorant like me. :)

You guys have been very helpful, and I really appreciate it.

Ya, it seems like the amp really is broken; which is a complete shame, cause it's been sitting in a box for two months because i didn't realize that the ACC wire was supposed to be High with 12v until yesterday :eek:, and had literally Just gotten it working, lol.

Oh well, so it goes.

Ya, probably the only viable solution would be to test each individual part for damage. The only one I would not be replacing is the chip itself; and I wouldn't know how to test for damage anyway.

I pretty much did everything wrong with this amp, but it certainly was a lesson to be had! I guess I was a bit too overconfident in my abilities as an electrician.

Thanks again everyone! I'll be sure to 'Thank' you each properly.
Hey, that's life man. You win some, you loose some.

* Don't bother to get it fixed, it will cost you more than to buy another one.
I know, I've been through the exact same thing than you.
Just get one from a place like Audiogon for car amps.

Cheer up, it's only a piece of car's electronic. ;)
Bob
 
H

highfigh

Seriously, I have no life.
Thanks a lot for taking the time for audio ignorant like me. :)

You guys have been very helpful, and I really appreciate it.

Ya, it seems like the amp really is broken; which is a complete shame, cause it's been sitting in a box for two months because i didn't realize that the ACC wire was supposed to be High with 12v until yesterday :eek:, and had literally Just gotten it working, lol.

Oh well, so it goes.

Ya, probably the only viable solution would be to test each individual part for damage. The only one I would not be replacing is the chip itself; and I wouldn't know how to test for damage anyway.

I pretty much did everything wrong with this amp, but it certainly was a lesson to be had! I guess I was a bit too overconfident in my abilities as an electrician.

Thanks again everyone! I'll be sure to 'Thank' you each properly.

If you didn't wire it so you made the battery connections at the speaker terminals, you didn't do everything wrong. (I've actually seen that done).

If you have a digital multi-meter:

1) Disconnect all of the speakers, set the channels to normal mode, power up the amp and measure for DC voltage at each channel's + and - speaker terminals. If you don't see much more than a few millivolts, shut the amp down and disconnect it from power.

2) With the power disconnected and no speakers connected, set the meter to Ohms and connect the leads to each channel's speaker terminals. If you see the meter reading OL (open, or higher than that range will allow), change to the next higher range (if it has auto-ranging, don't bother), reverse the leads on the terminals. If you see a number and it disappears, it may have hope. If you see low numbers, like .1 or anything close to that, it's likely that the output is shorted.

If all channels show a number that goes away, they may be OK. If it's only one channel, it may still be repairable, depending on the parts used.

If they seem OK:

Connect one speaker that you know is good to each channel, decrease that channel's input level control and plug the audio cable into the channel you connected the speaker to. Power up the amp and increase the input level. If it sounds OK, go to the next channel. Some amp manufacturers design them to self-protect to some degree.
 
TLS Guy

TLS Guy

Audioholic Jedi
If you didn't wire it so you made the battery connections at the speaker terminals, you didn't do everything wrong. (I've actually seen that done).

If you have a digital multi-meter:

1) Disconnect all of the speakers, set the channels to normal mode, power up the amp and measure for DC voltage at each channel's + and - speaker terminals. If you don't see much more than a few millivolts, shut the amp down and disconnect it from power.

2) With the power disconnected and no speakers connected, set the meter to Ohms and connect the leads to each channel's speaker terminals. If you see the meter reading OL (open, or higher than that range will allow), change to the next higher range (if it has auto-ranging, don't bother), reverse the leads on the terminals. If you see a number and it disappears, it may have hope. If you see low numbers, like .1 or anything close to that, it's likely that the output is shorted.

If all channels show a number that goes away, they may be OK. If it's only one channel, it may still be repairable, depending on the parts used.

If they seem OK:

Connect one speaker that you know is good to each channel, decrease that channel's input level control and plug the audio cable into the channel you connected the speaker to. Power up the amp and increase the input level. If it sounds OK, go to the next channel. Some amp manufacturers design them to self-protect to some degree.
Connecting the +ve terminals of any amps together, will blow any amps that I'm aware of instantly, and usually defeat the protection. Connecting the positives of amps together is always doing something wrong, very wrong.
 

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