Issue with amp- Need expert opinion

[4Rager]

I have a Kenwood Excelon X700-5 5 channel amp (1x 500w rms mono channel + 4x 40w rms channels).

A few months ago the front right door speaker stopped working and there was a boot print on the speaker grill. I assumed a friend accidentally kicked it and knocked a speaker connector loose. I took the door panel off and to my surprise both speaker wires appeared to be connected. Not wanting to take the seat out to mess with the rest of my wiring, I let it be for a while. I finally made the time to go back and fix it, and to my surprise after removing the door panel and messing with the connectors again, it started working again. That being said, it only produces about 30% of the volume of the left channel. Any ideas as to why? If it was a fuse or something it wouldn't be producing sound at all right?

 

[tigger]

You need to start with a process of elimination.

Verify that the balance and fader settings are correct.

Swap the RCAs R-L. Did the low volume move to the left? Yes - headunit or wiring, No - amp or speaker.

Put RCAs back. Take the left speaker out and hook it up to the right speaker connections. Is the output still low? Yes - not the speaker, No - speaker is damaged.

Then run a wire straight from the right channel to a speaker. Output still low? Yes - amp is bad. No - wiring is bad.

 

[4Rager]

You need to start with a process of elimination.

Verify that the balance and fader settings are correct.

Swap the RCAs R-L. Did the low volume move to the left? Yes - headunit or wiring, No - amp or speaker.

Put RCAs back. Take the left speaker out and hook it up to the right speaker connections. Is the output still low? Yes - not the speaker, No - speaker is damaged.

Then run a wire straight from the right channel to a speaker. Output still low? Yes - amp is bad. No - wiring is bad.

Sorry, I forgot to mention I tested the speaker by switching the inputs on the amp, so I know the speaker isn't damaged. It seems to be the signal coming from that channel on the amp is weak.

 

[tigger]

Sorry, I forgot to mention I tested the speaker by switching the inputs on the amp, so I know the speaker isn't damaged. It seems to be the signal coming from that channel on the amp is weak.

I don't see how that would tell you if the speaker was bad or good. Are you sure you don't mean you swapped the outputs?

 

[4Rager]

I don't see how that would tell you if the speaker was bad or good. Are you sure you don't mean you swapped the outputs?

You're right, I meant outputs from the amp. The right-front channel is the one that is weak, so I took the RF outputs and connected them to the left-front outputs and the speaker worked normally.

 

[tigger]

You're right, I meant outputs from the amp. The right-front channel is the one that is weak, so I took the RF outputs and connected them to the left-front outputs and the speaker worked normally.

Did you swap the inputs to see if it was the source or the amp?

 

[4Rager]

Did you swap the inputs to see if it was the source or the amp?

I use an LC6i line-out converter to get the powered signal from the HU to the amp, so I switched the outputs from the amp to test the speaker (which was working fine) then I switched the left and right inputs from the HU to the LC6i which also made the right speaker work fine again. It really seems like that particular channel on the lost some of it's power.

 

[tigger]

I use an LC6i line-out converter to get the powered signal from the HU to the amp, so I switched the outputs from the amp to test the speaker (which was working fine) then I switched the left and right inputs from the HU to the LC6i which also made the right speaker work fine again. It really seems like that particular channel on the lost some of it's power.

If you swapped the inputs and the right channel worked correctly then the issue isn't with the amp. It is prior to the amp.

Check the input/output levels on the LC6i (never used one so not sure what settings it has.

When you swapped the inputs, did the signal loss move to the left?

 

[truckhigh]

i would guess you have a loose connection in the hi level inputs. Did you run new speaker wire to the door or did you bypass it by the head unit. i don't like high level inputs for this reason. There are some stand alone high level inputs that have adjustments on them.

 

[riceandpho]

sounds like a bad ground connection on the rca, bad solder point on amp maybe too.

 

[4Rager]

i would guess you have a loose connection in the hi level inputs. Did you run new speaker wire to the door or did you bypass it by the head unit. i don't like high level inputs for this reason. There are some stand alone high level inputs that have adjustments on them.

This is where I kinda cut a corner. Initially I was going to run new speaker wire to every door. But after running speaker wire to the RF door, I realized it would be a lot of work and I would lose the tailgate speakers. So that being said, the speaker that is under-performing is the ONE speaker that IS wired directly to the amp, the rest I intercepted behind the HU. The only difference should be thinner gauge stock wiring and longer runs, so if anything the RF should be getting the best signal. I should have some more time to troubleshoot later this week, so I'll check back after that. Thanks for the help guys.

 

[truckhigh]

This is where I kinda cut a corner. Initially I was going to run new speaker wire to every door. But after running speaker wire to the RF door, I realized it would be a lot of work and I would lose the tailgate speakers. So that being said, the speaker that is under-performing is the ONE speaker that IS wired directly to the amp, the rest I intercepted behind the HU. The only difference should be thinner gauge stock wiring and longer runs, so if anything the RF should be getting the best signal. I should have some more time to troubleshoot later this week, so I'll check back after that. Thanks for the help guys.

You might be running at the wrong ohm o that speaker now. em stereos are normally odd ohm'ed set ups. it could be bridged with the rear speaker or tweeter somewhere. just run the door like the other ones or just run some new wire. I'm not sure about what ohm load your amp takes.

 

[4Rager]

You might be running at the wrong ohm o that speaker now. em stereos are normally odd ohm'ed set ups. it could be bridged with the rear speaker or tweeter somewhere. just run the door like the other ones or just run some new wire. I'm not sure about what ohm load your amp takes.

It's 4 ohms for the speaker channels and 2 ohms on the mono channel, so I matched the speakers and sub with that. Good point though, I never thought about that aspect of reusing the stock wiring.

 

[4Rager]

So I finally got around to removing the seat to do some more troubleshooting. I double checked all the input wiring from the head unit, to the LOC, to the amp, and it really does appear that the right-front output channel on the amp is weak for some reason. I switched the Front left & right outputs to confirm the speaker working, and it was. My thoughts now are that during the period where the speaker was disconnected, maybe the wires were touching and it partially burnt out that channel. Soon I'm going to redo all the wiring directly to the amp like I should have done from the beginning, but eventually I guess I'll need to replace the amp.

 

[riceandpho]

have you check if the polarity on the speaker input is correct on the lc6?