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trixta
09-01-2007, 19:36
Well,

I was looking around on the internet and found the recommended box volume and port diameter/length, so I thought I would remake my install to folllow these guidelines....

I did this, so now have a Kenwood KFC W5209 (cheap, but not the point) in a 1.25cubic ft box with a 4" diameter, 6" long port. I fitted it earlier on, and thought I would test it...

I put a track on and it plays fine, sounds pretty good actually. The problem started happening when i changed track... As I change track, put the volume on zero, or turn off the headuint, the sub suddenly pops out to full excursion, stays there for about 2 seconds, then pops in as far as it can go, then pops to the middle again, shifting quite a bit of air...

Its pretty scary because I don't know if its going to break my sub. I put the fader on the headunit to full front, but it still does it skipping track etc. Obviously when I unlplugged the RCAs it stopped. I'm thinking it's probably sometihng to do with the new size port, but I put my hand over it and it still did it. Not sure if thats enough to cover it...

I was wondering if anyone else has ever encountered this problem or if anyone knows what's going on... much appreciated
trixta
09-01-2007, 19:37
oh, i forgot, its a Vibe Black Box 3 powering it. (300w rms)
Martin
09-01-2007, 19:41
sub popping = bad earth.

either bad earth on speaker cable, or bad earth to chassis.

this is under the rockford fosgate trouble shoot area on their webpage, its not just me replying ITS YOUR EARTH to every thread lol
trixta
09-01-2007, 19:43
lol.
What do you mean by earth on speaker cable?:woops:
Martin
09-01-2007, 19:43
sorry, speaker negative.
trixta
09-01-2007, 19:44
k thanks..nice new car btw
Martin
09-01-2007, 19:49
why thanks. it does the job.

try earthing with thicker gauge. also, where is your earth point? this may be the problem if its a gay place.
trixta
09-01-2007, 19:52
its here, (http://i44.photobucket.com/albums/f23/foldincheese/DSC00203.jpg) and sanded, so pretty heterosexual...:P
trixta
10-01-2007, 20:11
i used a different phono lead and the problem stopped...
trixta
13-01-2007, 14:01
turns out ive bust the rear preout on teh headunit by shorting the phono cable :(
Martin
13-01-2007, 22:43
bust the pre out?

how on earth did u do that?
trixta
14-01-2007, 09:34
i dont know, i think it was when i had the amp out to go to the airport, so the phono cables were loose to short out on anything they felt like...
Martin
14-01-2007, 10:46
well the positive on a phot cable is the pin in the middle, the outside is negative. so it woudlve been hard to short it out