Very Odd Observation!!!

[T.O 240sx]

i finished installing my system... 2 Infinity subs and an Audiobahn amp; everything works fine, the wiring is fine but there is one problem....lets assume the volume is at '15' to make matters easy, the subs are pounding at this point... when my trunk lid is open everything is fine but when i close my trunk lid the music starts to skip like crazy to the point where you have to stop it.my question is how could this be possible?... i checked to see if any wires were even touching the any part of the trunk lid, and theres nothing.

i attached a pic of the setup... sorry its not that clear... but you can still see the location of basically everything

[mrflip69]

Do you have a cd changer in the trunk that's doing the skipping? When the trunk is closed, you'll have a higher air pressure which is causing the problem you're experiencing. Likewise with windows. For your subs to be pounding at only volume 15, maybe you need to adjust (lower) your gains a tad bit.

[T.O 240sx]

i see i seei dont have a cd changer; just the decki was thinking it had something to do with air pressure but i wasn't too sure... ill try it with the windows/sunroof open and the back seats down and see what effect it has on itthanks for the info!

[Rex]

Does it skip/cut in and out if you do the same thing while listening to the radio??

[Silvia2b]

Do you have the car running or not when you are testing? low current supply can be an issue, but doesn't explain your trunk opening/closing issue.

[T.O 240sx]

hey Rexi havent tried it with the radio... ill check it out though and let you know

Silvia2byeah, the car is running... its weird!... well mrflip69 mentioned something about air pressure... i guess theres too much or something... my car is in the shop right now, but when i get it back ill check it out again.

thanks for the help!

[Simmsled]

This is a classic cd skipping problem. What happens when your trunk is open is this... the sub does not have a surface that absorbs/reflects sound waves and air pressure differential. (This basically means that the sound is escaping into the air and not channeled into your car.) This is noticable by the sound not being as loud inside as when the trunk is closed.

SO... when the trunk is closed, your trunk lid or the back of your trunk (wherever you have your sub pointed) becomes a "sound board" that absorbs/reflects sound waves and the resulting air pressure within it vibrates that surface. Your cd player is attached to your car and since the sub is vibrating your car, the vibration from the car is absorbed in anything that can move inside. Thats why we have rattles. SO those rattles are felt in the cd player... the cd skips and you get mad.

You can remedy this by trying a couple things. Aim the sub a different way in the car, make sure that your cd player is SECURELY and TIGHTLY fastened to your car, or insulate your trunk with dynamat or brown bread or whatever. I reccommend all three, but do what you can and see if it works out.

ALSO, in your case your sub gain may be a little high as you are getting high SPL from level 15 on your deck. You can check your gain by keeping the trunk open and turning up your system while listening for audible distortion from your sub. That level that you have it turned up to is the max level that the subs will play.

OR...

That being said, once your amplifier is feeding your subs with the max amount of power, your subs will get no louder. If your subs do not get any louder past a certain volume, this is the max loudness attainable from your system. Use this method if you cannot hear distortion from your sub.

GOOD LUCK!!

[T.O 240sx]

hey Simmsled... thats for the tipsso its really a matter of vibration and nothing else which is causing the cd to skip.just a question... does it really matter which way your subs are facing?... i mean, whether it be towards the back, front, ground, or up?right now, my subs are facing the front of the car... i could try putting them the other way to see if that helps.i have the trunk dynamated already, but i think where my problem is, is the fastening of the deck, im 100% sure that it can be more secure.i do play around the the gain on the amp, which does help... it may be too high, but when i turn it down lower the subs dont pound the way i want them too!

when i get my car back, i will take your advice and check everything out... thanks again

[Rex]

Some CD player's have adjustments that you can make if they aren't completely parallel to the ground. If it's sloping downhill towards the front of the car, that may make it more likely to skip.

[T.O 240sx]

Hey Rexim sure my deck is not parallel to the group... its on a decline. i didnt put on the screws into the deck.i've never had this problem before, but then again, i never had this quality subs/amp setup...its much more powerful now than before.thanks!

[Simmsled]

well, if you think that your cd player needs to be more securely fastened to your car then that has got to be the main issue. but it does matter where you face your subs. if you face them to the back or corners, in my experience, you get the biggest gain in spl. but... you also get the most rattles. honestly it will vary with the amount of sound deadening, power, sub size, location... etc . there are so many variables. i suggest experimenting. thats one thing that I would do when I started out in car audio. ive found out that it is one of the best ways to get to know your car and more about systems. good luck man.