After playing for a while, the mid-bass of my Polk Components has a tendency to sound weak and scratchy as if the speaker is blown. However, the last time I heard this happen, I took the grill off and removed it from my door and as soon as I removed it from the door it was playing clean.

I reinstalled it, it sounded fin until I put the last screw in. As I tightened the screw it began to sound crappy. So I took that screw out and left it playing like that. It ran fine for another 2 weeks, but now the scratchiness has returned - its the same story: As I remove the speaker from the door, my sound cleans up. Put it back in it starts to junk out. The speakers are not newly installed. They have been playing in this car for roughly a year - I never touched them since I installed them, and this is the first issue I've had with them.

Does Anyone have any ideas?
It is pissing annoying!

Ryan

 

maybe by tightening thru screws as tight as you do its distorting the cone of the woofer, creating uneven suspension. Might be one thing to look at. To Hear if its blown, take it out, hold it to your ear and slightly push on the cone evenly, see if you can hear anything. If its blown you will hear something.

 

You may be twisting the frame. Alternatively, you might be grounding out a speaker lead.

 

can you get a pic of the door without the skin on it so we can see the speaker
a pic of the speaker
i would like a pic of the wires to the speaker too
see if your wires have a cut that is hitting the car

 

I think a slightly twisted frame may be the case.
I was playing with it last night and as it was playing in my hands (still mounted to my wooden baffle that allows the 5.25 to fit in a 4.5 hole) I tried twisting the frame a little bit and that did make the sound get worse. However, now it sounds like there is a bit of scratching both in AND out of the door. I tried to twist the frame (only with my hands) to hear if I could make it go away. I couldn’t I still hear a slight buzz or crackle that makes a CD sound like it is broadcast radio.

As for a speaker lead shorting out against the car body, I thought of that one too. But then I discovered as I was taking the speaker out that when one of the leads touches the car body the amp cuts all power to that channel – completely off – nothing in between.

I’m not using any factory wire. I’m using the wire that came with the speakers (still not the greatest wire, but better than factory)

I've attached a picture. I hope I attached it right.

 

I just tried that. I had some interesting results.
When I pushed with even pressure I could hear a slight hint of friction, but not scratching - more of a smooth rub.
But when I tried uneven pressure (only pushing with one finger) half of the speaker was smooth and clean but the other half was beginning to scratch. In relationship to the “Polk” label on the dust cap from 7:30 to 1:30 was clean and smooth. 2:00 to 7:00 was rough. (So in relationship to the above picture, it is pretty much a horizontal line -with a slight downward tilt to the right of the picture- through the speaker. Top half is smooth, bottom half has slight friction)

So, is that an indication that part of the coil is blown, or that the basket/frame is warped?

I’ve rotated the speaker 180 degrees on my mounting baffle and I still get the same rough/smooth sounds in the same locations as mentioned above. However, equal pressure is now smooth and clean. I’m going to reinstall it and go for a little test drive.

Thanks guys
Ryan

P.S. I just found out that even the magnets on these little comps are still big enough to mess up my old-school tube monitor.

 

if it makes a sound everytime that last screw goes in, is your mounting location warped?

 

I am starting to think that. As I mentioned above, I rotated the speaker 180 degrees on the the mount and in the last 24 hours I haven't heard any problems. So I suppose that now, I am unwarping the damage that has been done to the speaker over the last year.

Here is my thought: Over the next several months, once a month I am going to take the speaker out and check to see if it has returned to an even all around response. Once I've acheived that, I'll address the the issue of my warped mounting location. Does anyone have any suggestions about how I can check the "trueness" of my mounting surface?

Thanks

(ps - could this explain why the pole piece on my last polk coaxial let-go and so destroying the speaker? Can a warped mounting location do that kind of sustained damage to a speaker?)

 

cut a peice of mdf out thats a bit bigger then your mounting location like a circle , and press it up against cuz im pretty sure mdf is truely level.. and look for gap's