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More Bass In Your FSJ

Contributed By: Dan Bumgardner

Kevin,
If you want more BASS your need one of two things or both. Power and larger drivers. Bigger drivers push more air and have also tend to a have a lower FS (Free air resonance).

Here is a quick test for correct phase on speakers. Balance control set to center-little or no bass, balance turned to left or right and bass improves? You have a speaker out of phase. If you have one speaker wired correctly and the other reversed (+&-) the 2 speakers will cancel each other out and low frequencies will be reduced. Also, the rear of the speaker must be sealed or seperated from the front. My guess is that since they are under the dash, they are not sealed. You need to either put them in a enclosure or for a couple of bucks put a foam baffle on the rear of the speaker. These are premolded and come in all speaker sizes and come in two different depths(reg & slim line).

If the first two things didnt work, get your checkbook out. First check the max RMS or continuous power rating of your speakers. If the RMS power of the radio is only 7watts per channel and your speakers are rated for 100w RMS you will need an amplifier in the 100 w range. Ignore all peak power ratings on speakers and amps they are meaningless but, look great for advertising. Always go with RMS values. When choosing an amp it is always better to have alittle too much power then not enough. Golden rule: stay within 10% +/- of the max RMS power rating of speaker. If you do all of this and you still need more bass, you need to move more air. SInce you dont want to pull the side panels or loose cargo space I'd say you have two options. Either something like a Amplified Bazooka 8" or 10" bass tube mounted to wheelwell or if you've go a 2dr you could mount it vertically just behind the B-pillar. Might make it alittle tight for someone getting in the back though. If you want to keep it clean go with either a 6 1/2" or 8", if it wil fit, mounted under each seat and build the enclosure yourself. Just make sure the speaker is designed to work in a small box. Check the cu ft of box/enclosure and match with recommended box size of speaker. H"xW"xD" divided by 1728=cu ft. Use the 10% rule here too, And of course you will need an amp for this. General rule: sealed boxes sound tighter/more accurate but arent as loud. Ported boxes loud and "boomy". Enjoy!

Kevin wrote:
"Installed a Pioneer deck and some Kenwood 6"round speakers under the dash. The problem I have now is base, I need base. I don't want to tear into the doors and don't plan on tearing into the panels in the cargo area, already got those reinforced with metal and installed locks. What are my options now??"

Dan
76 360/400/QT/WT

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