Amp Issue?

[coolcalico 10+ year member]

I have a 2008 Scion tC. I got a line out converter to run an amp, which would be powering 1 10" sub. My sub is a Rockford P3, DVC 4ohm --- wired to run with a 2ohm load off the amp.

Someone gave me an amp as a gift --- def not the one I would have choose myself. Kenwood KAC-8103D

Specs are:

4ohms = 300x1

2ohms = 500x1

Having hatchbacks in the past, I have had a lot less power running to subs and had decent bass. My problem is my sub is hardly moving. I have power on my amp (I tapped into a switched power wire off of my headunit for that). Using my volt meter, I read adequate power coming from all sources. My sub is just hardly moving with the gains up. I've installed plenty in the past, so I have an idea of how everything works... I've double checked my wiring, and everything appears to be correct.

The only thing that throws me for a loop is this particular mono amp has 4 outputs, 2 (-) & 2 (+). I was running off of 1 set, since it's not bridgable.

Is this incorrectly wired? I think so... but wanted to double check, just incase.

My only assumption can be that something is wrong with the amp. Unfortunatly, I sold all my extra car audio equipment I had sitting in my closet & don't have a spare amp to test with... This is also my first time attempting to run an amp off a stock headunit with a line out adapter.

Suggestions are appreciated. This thing is driving me nuts! //content.invisioncic.com/y282845/emoticons/crazy.gif.c13912c32de98515d3142759a824dae7.gif

Click to read more...

 

[audioatg 10+ year member]

I would first check the line out converter. I have installed them before and the ones I had, Were adjustable. Had the same thing happen to me bass was really low amp gains were good check that adjusted it up and got good bass after that.

 

[coolcalico 10+ year member]

I have, I've turned the gains up the entire way, and still had the same effect. Funny thing is, I had an extra one of these, and put it in, just to try, and had the same problem. I've also read the voltage coming out of it, and it is where it should be.

 

[CarAudioGuru 10+ year member]

From what I have read in the manual you should be able to directly connect your OEM headunit to the Kenwood, with no adapters.

Sounds like you are not getting enough input signal, or you wired your woofers out of phase to each other.

As a test try hooking the Headunit directly to the Kenwood using the speaker level inputs on the amp (no other adapters in-line!!)

See what that does. If nothing changes, trying hooking just ONE (1) of the voice coils up. DO NOT play it too loud as this is just a test.

Another good test to hook up your IPod to the RCA inputs. it is only 0.7 volts out,

but you should get some reasonable output from it.

Like to see what it was after your tests.

 

[CarAudioGuru 10+ year member]

Voltage coming out of what? Also make sure your run 8 guage (or 4 guage ) power wire directly to the battery for this amp.

DO NOT skimp on the power flow! Biggest mistake you can make.

 

[coolcalico 10+ year member]

A few things I forgot to mention.... //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

The kenwood did come with the inline hookup, as you mentioned. Out of frustration (and to eliminate the converter as the problem source), I did use this as well. Same problem, the sub hardly moved.

I also tried hooking up just one VC, same results. I actually tried hooking it up to both VCs independantly incase a VC was damaged on the sub itself (although I puchased it new).

Here's a curious question... I should be getting a reading from the (+) & (-) terminals on the amp, correct? I am getting none. I reverfied that the power source was getting ample power (12.4v), the remote wire (12.4) and that the ground wire was secured properly. Using the harness kenwood supplied to bipass the RCA/line out converter, I measured their voltage... 6.2v on each wire. Every input on the amp is getting correct voltage, yet, I have no power coming out of the terminals.

The power light is on, and it is NOT in protection mode... indicating that it SHOULD be working just fine.

To go more indepth about the movement of the sub... you can't really see it... only feel it moving. Its in a ported box, and I also feel no whoosh of air coming from the port because, like I said, the sub is hardly moving.

Anything else I can try? I'm pulling my hair out over this one... My gut instinct is telling me the amp is my problem. I'm honestly feeling retarded because I've done tons of other installs in the past.

 

[coolcalico 10+ year member]

Voltage coming out of what? Also make sure your run 8 guage (or 4 guage ) power wire directly to the battery for this amp.
DO NOT skimp on the power flow! Biggest mistake you can make.

I have 4g wire running from the battery terminal (fused of course) to the trunk area of the car, it reads 12.4v. The ground wire is bolted underneath the rear seat. I scratched away the paint, and used a star washer to better grip it into the metal. The remote wire is a switched power wire I located in the back of my headunit. It reads 12.4v.

 

[boomzilla 10+ year member]

it could be the box, is it a prefab?

also it could be some settings on the headunit, sometimes when i change setups i need to adjust my hu a little bit, but i just forgot its a stock radio.... hmmm is there noone local that has another amp you can test out?

 

[CarAudioGuru 10+ year member]

Try the IPod trick and a different speaker (even a midrange, anything!)

Maybe a buddies "known" working sub enclosure. Try it. Just so you know your not crazy??

With your meter on AC volts the speaker out should read (at full tilt boogie!!) about 40 volts (into a 4 ohm load) or 28ish volts into a 2 ohm load.