Is this amp blown?

[ShaneSauce 2]

Got a super old school 40x4 sony from a buddy of a mine and he said it worked.

Spent all day running all the wires, got it hooked up and the power light comes on..

But there is something wrong, the only way I can describe it is a very loud thumping every second or so..

I have 2 sets of rca's ran and I think that could be the problem is me not having them set up right.

On the back of my head unit I have the rca's hooked up to the sub amp fine.

Then I have 2 pre-outs one set for the front and one set for the rear, well on the amp there is a,b,c,d and I'm not sure how this should be set up..

And the 2 sets of rca's are different idk if that makes a difference.

Is this amp blown or do I just have it hooked up wrong.

[bigrank916 72]

Try all different variations of connections to the rcas on the amp and if you still have the same sound then Id say there is a problem with the amp.

[jonbearsmt 919]

get your ipod or MP3 player and a set of mini to rca cables and check it out for sure... also check your fuse and your ground ....somtimes the fuse can be blown or bad and the light with still light up as it pulling from the remote wire... same goes for the ground.. it can be getting a small ground from the amp frame but not to the ground input.

[ShaneSauce 2]

get your ipod or MP3 player and a set of mini to rca cables and check it out for sure... also check your fuse and your ground ....somtimes the fuse can be blown or bad and the light with still light up as it pulling from the remote wire... same goes for the ground.. it can be getting a small ground from the amp frame but not to the ground input.

ah i don't have a set of those cables for the ipod.

but i will go check out the fuse and ground make sure those are good..

try switching the rca's around and see what happens.

ill be back shortly

[ShaneSauce 2]

Ok guys..

Part of the problem was a bad rca.. got that fixed.

I'm in the process of re-wiring all of the speakers, its a huge mess behind the head unit.

Now I ran into another problem.

Engine noise, I ran the power wire separate from the rca's and I'm still getting a crapload of engine noise/whine and static.

How do I stop this I don't even know where to begin.

[Hell-Razor 0]

Now I ran into another problem.

Engine noise, I ran the power wire separate from the rca's and I'm still getting a crapload of engine noise/whine and static.

double and triple check your gruonds. Even try re wiring your ground with a bigger gauge.

[bigrank916 72]

Ok guys..

Part of the problem was a bad rca.. got that fixed.

I'm in the process of re-wiring all of the speakers, its a huge mess behind the head unit.

Now I ran into another problem.

Engine noise, I ran the power wire separate from the rca's and I'm still getting a crapload of engine noise/whine and static.

How do I stop this I don't even know where to begin.

Make sure all your grounds are properly cleaned of paint and secure.

[ShaneSauce 2]

I upgraded the ground today and I'm still getting a ton of engine noise.

Its bolted to the seat so idk..

[jcarter1885 995]

Did you sand down the grounds in the car. I would suggest upgrading your BIG 3 wiring, thats what really helped me get rid of my engine noise completely.

[ShaneSauce 2]

I'm gonna take a wire wheel to it tomorrow.

And today I got it all working besides the engine noise but my front left speaker wasn't working at all.

When I would plug the rca's in it would pop but no sound after that.

I'm guessing the positive and negatives are backwards or something...

Its all just a big confusing mess and having to go to school until 1 then go straight to work until 10 doesn't help..

I need some free time!

[KU40 173]

Having positive and negative backwards doesn't cause any problems for the speaker. In fact I wired one of my mids backwards on purpose so that the phase would be better for where I sit.

Try hooking the sub amp RCAs into the Sony amp, and vice versa hooking the sony amp RCAs into the sub amp.

But with engine noise it's usually a grounding problem. If you scrape the paint from under the amp ground, head unit ground, and the main battery ground and it's still there, try switching grounding spots for both the amp and head unit.

[ShaneSauce 2]

Grounded the amp directly to the frame and got noise.

Switched amps with my dads 2 channel and still got noise.

So a bad ground somewhere in the car I'm assuming?

My kicker doesn't have this problem.

[jcarter1885 995]

Grounded the amp directly to the frame and got noise.

Switched amps with my dads 2 channel and still got noise.

So a bad ground somewhere in the car I'm assuming?

My kicker doesn't have this problem.

What kinda car, I noticed that my car came with horrible grounds from the beginning. The battery to frame and engine block to frame were painted and not sanded off, once I upgraded those wires and got the paint removed my eninge noise went away completely.

[ulrisa 26]

You could try a ground loop isolator, some people have luck with those. I've had this problem pretty bad before, I had to replace my head unit because I had a blown pico fuse in my pioneer, I'm not sure if Kenwoods use the same type of fuses on the rcas, just a thought. Also, somewhere along the line my antenna's ground got messed up, and it fixed my whine when I disconnected it. It's just strange that you are only getting this on your highs/mids amp.

Try disconnecting the rcas from the h/u and turning the car/amp on to see if the noise is there, if it is then it is probably something with the cables, if it's only there when they are connected to the h/u then it is probably something with the h/u or something connecting to the h/u. Also, make sure to put something over the rca's so they don't make contact with anything while you do this.

I hope this helps narrow down your problem.

[ShaneSauce 2]

I think I have this figured out..

It is my head unit I am almost 99% sure, the reason I say this is because my dad got a kenwood deck a couple months ago very similar to mine and we traded for a couple days.

When he put my deck in his truck he had all kinds of engine noise and static. because he is running a 4 channel amp in his truck and I wasn't.

So when he plugged in his rca's into the front and rear pre-outs on my deck it made the static.

We put the deck back in my car and I never used those pre-outs so that's why I didn't get noise until I tried to install a amp. Which is why I was getting static and whatnot..

It must be the head unit!

Gonna put my dads back in my car and see if that solves the problem.

[efxtruck 0]

You should also check the placement of you power wires and RCA's if you have wires over lapping in any places you can get engine noise.