Just wanting people thought/opinions on an on going incident I have been going through ever since buying my SR124 subwoofers.
I have 2 Polk audio SR124, SVC 12" subwoofers, each powered off their own Polk audio C300.2 Feeding them is currently an Alpine CDA-9887, prior to this was an Eclipse CD8455.
While driving I noticed that the bass was very weak, which is odd for me as my setup is purely an SQ tune. So after getting to my destination I open up the boot to find that one sub isn't working... next step is turn it all off and evaluate the damage at home. At the time my HU (CD8455) was at ~60 out of 80.
After various voltage and continuity checks, I place the DMM on the subwoofers terminals to get a reading of 0ohms. With the terminals still wired to the DMM I press the cone lightly to see if the Voice coil has let go, to my surprise it is free flowing (normal) and the Ohm meter starts reading! however returns to 0ohms, when the sub is at rest.
After sending the subwoofer away for repairs, it is found the the lead between the terminal and voice coil had snapped/de-soldered for what ever reason. repaired under warrenty :) smile back on the face and all is fantastic!
A few weeks later... same thing again! This time with the other sub! send it away and reported back to be the same problem! However this time they replace the subwoofer. yet again big smiles on my face, as I really do love the sound from these speakers!
I put it down to been a bad batch/run or they were finished on a Friday afternoon... these things happen, the serial numbers were one digit off each other.
So all is fine and I'm driving along when I hear that oh to common sound of unbalanced sub-bass... sure enough... the original repaired subwoofer has come to the same position. reading 0ohms... move the cone and you get a reading, but returns to 0 when at rest....
In all honesty I am at a loss as to what is happening, I have been through many woofers in my life and have never had one fail, let alone 3 in as many months!
All of the gains are set using a DMM and CRO and after the first incident they were turned down further from fear of another dead subwoofer. Those that have been in my car have commented on the superb sound but have also asked why they cant hear much bass, again showing that I don't try to over drive my speakers. They are in their own sealed enclosure (~1cf after displacement) and crossed over 80hz@24db or 63hz@24db depending on the tune.
I did read a while back about someone having the lead in question snap in half. Has anyone had any other issues with their SR12's? or does anyone have any thoughts regarding the issues? I am in Australia so calling Polk direct is something will be my last resort, The importer into Australia is currently away for our holiday period, so cannot be contacted and i'd like to get a feel for possible case before i get the "gain isn't a volume control" lecture, you cooked it buy a replacement.
Any help would really be appreciated!
Current setup is:
Polk Audio SR6500
Polk Audio SR124 times 2
Polk Audio C400.4
Polk Audio C300.2 times 2
with the C400.4 biamp'ing the SR6500's.