lithium

thanks for the explanation. I understand how to read the graphs for the most part but I dont know what conclusions to draw from them (ie. is the bl curve good or bad). I probably need to read a lot more on speaker design as well. I won't clutter your thread up with this, gl with the sub.

for anyone who wishes to read more on the topic, http://en.wikipedia.org/wiki/Sound_localization

if you want anyone's help you should try your best to answers our questions.

if you're listening to some dynamic music and observing dips in voltage remember that you're at the mercy of the voltmeters resolution. It could be dipping much below that momentarily. whether or not that's a bad thing, i dont know. depends on other factors, what the amp can handle, etc.

Graphs! i should learn how to interpret these some day.

5 min expoxy or amazing goop would also work.

i dont think felt would isolate any rattles. ccf is his best bet

he's suggesting upgrading the front stage. which would require a 2 way or 3 way set up with large midbass speaker which could extend down to ~60 hz and cover the gap in frequency response. i dont think your ready to throw more money at the problem. its more likely you can alleviate the problem with some install changes.

i would try opening up the rear deck, remove the rear speakers. if you're interested in a new enclosure idea this would be a good application of a bandpass enclosure (the vent firing solely thru the ski hole). however you may not have enough room in the trunk. edit: additionally you can try a simple sealed enclosure and seal it to the ski hole in the rear seat.

that explains a lot

how's port forward or to either side?

leave the stock wire in and add the 2 gauge. should be fine. the runs are fairly short i assume. could double up a long run if you got extra wire.

i'd argue that the amount of power really isn't as important as the quality of the amp. additionally, spl gains from additional power are very minimal. calculate the theoretical increase in spl between 2000 and 3000 watts.

the enviroment does change the frequency response of the subwoofer. google cabin gain. my point about modeling subs at different tuning frequencies was ment to show that tuning too low waste potential output at frequencies that actually appear in music.

flucation in voltage is pretty normal from what i understand. and the amp looks sketchy as fuck. don't quite understand the fixation on big power. much easier to put that budget into a decent amp and more sub. hit the f/s section for an amp, new equipment is out of your price range

not nessarily for eye strain but i use an program called flux. turns the screen color to a warm orange/yellow during the evening/night.

http://www.parts-express.com/cat/woofers-subwoofers-midrange-speakers/31?kg=497|3909 model them versus the fi's and tell us who wins

yes please do! i wouldn't tune so low unless u listen to nothing but chopped up and slowed stuff. they're not enough low frequency content in most music to justify tuning below 30. im sure there are exception. model a few boxes.

wouldn't a pro audio substage make more sense?

should be fine as well. mostly an aesthetic choice when it comes to decent amps. seems like the ppi is significantly cheaper?

doesn't matter. 1000 vs 1500 watts isn't audible

A sk-1500? That amp will do more then rated power @ 14.4 volts. doesn't matter if it does, you wouldn't able to hear a difference

set the lowpass on the sub to 80 or 100 and verify that all eq is disable (no bass boost, etc), is the null still present? other things to try, move the enclosure around in the trunk. edit: you can also sit in different seats and test if the null is present elsewhere edit2: i should've mentioned, disable the components for now. if they were causing cancellation with the sub that would be one thing but you've said its present with just the sub playing

model the sub in the enclosure you have now VS a larger enclosure. guaranteed it will have more low end! at the very least, spend the 40 bucks to build a new box and test it out!