System set up correct??

[Twista89 10+ year member]

Just had a quick question right now..Got my DMM in today and went out and played with it on my system. I was playing my music normally trunk closed and it was weird because I pushed my subs more against my trunk lid recently and was outside the car and noticed that I didnt hear any rattling coming from the trunk but was hearing all types of metal flexing up front by the mirrors and the doors. Is that a good sign seeing as I dont have any sound damp material(dont plan on putting any in this car). When the subs where farther from the trunk lid I was hearing nothing but trunk rattles and nothing up front...What happened???

If I play a 50hz tone though the car starts to rattle everywhere though lol...just noticed this with music..

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[keep_hope_alive Premium Member]

sub location determines which room modes are excited. when it was toward the seats you had phase interference up at the dash reducing output. back at the rear the direct and reflected waves are coherent. also, location determines what physical modes are excited.

 

[Twista89 10+ year member]

u know of any good reads on this type of information...this stuff sounds really interesting to want to learn about!!

 

[Twista89 10+ year member]

also had another question...I was reading up on some material that was talking about how a charging system should start out at a high voltage like 14.4-5 and when the batteries get close to full, start to drop off to around 13.2-5 to slow gases and prolong the batteries life. So I was wondering does this apply to car charging systems as well?? I know when I first start my car up cold the voltages are around 14.4 up front and get to around 14.1 at the rear battery. It will stay at that level until I start turning the system up to like 80% of my max gain setting for a good 3-4 songs or so and then drop to 13.8 up front and sometimes get to 13.4 at the rear....is that ok for keeping my 9A31 fresh?? No dimming or anything just want a good electrical system for what I can do with my 105 amps....

 

[FenixAudio 10+ year member]

your charging system should stay at 14.4 volts in a perfect world. if your droping to 13.5 thats a large drop and most likely indicates that you will need a larger alt if you want to relly bang for a long time with out driving the car. however, you should not be losing wattage. most apms have a regualted power supply that plays the same output between a certain input voltge. Usually between 13.4v and 14.4v. each amp is a little different though. most major brands have regualted power supplies.