I have a 1986 Rx-7 GXL I'm Hooking up my alpine system but i noticed when changing the 4.5's under the glove compartment that there was a box for the speaker which i guess is supposed to enhance the bass but it sounds like crap...i installed the speakers and all i hear is muffled bass...i cut a hole in the back of the box to let the air pass through but it still didn't work...any suggestions? and oh yeah i'm hooking up either one 12 inch type R sub from alpine or the pentagon shaped explode series...which will sound better in the rx-7....your feed back is greatly appreciated...

 

Go w/ the type R altho I recommend solobarics because they use very little airspace and they have very good SQ. *** an xplode, unless your on a tight budget

 

Can someone explain how to get rid of that vibration from the right 4.5 speaker under the dash?

 

get rid of the box.

 

there is sum circuitry in the box and i'm not qute sure what its for or else i would remove the box...

 

You could cut the circuits out of the box. If you are going to get rid of the box, your speakers will be running off of free air, which will be a little weird, but shouldnt make that much of a difference as long as your not trying to get bass out of them. Definately go with the Type R and not the Xplode. A solobaric is good, but more expensive and also your going to need a bigger amp to effectively power the solobaric. I would reccomend the Type R if your set on alpine.

 

If you just suspend the speaker under the dash w/ no attempt at enclosing it somehow, you'll get nothing but mids and highs from it. The sub will take care of the low bass, but there will be a very noticeable lack of midbass that should exist in the front of your car.

Ideally, you'll want to get your directional midbass up front and let your sub work the lower freq's that are non directional, ie under 125 hz. Consider custom installing 5.25's in the lower corner of the doors unless you can figure out a better way of mounting the 4s under the dash.

Regards,
Tony Alvarez
93 Rx7 currently (used to own a 94 and an 87)

 

find some s5 (89-91) door pannels, they have speaker provisions in them already, also all the circuitry in the box is the factory amp which you won't use with an aftermarket head unit anyways

 

The box contains the amp for the front speakers. You can bypass it fairly easily. On the factory connector, you just need to patch over the wires for the front speakers from the radio. You can trace these with a multimeter or the FSM schematics.

 

Oh, and the 86-88 doors do not have the speaker openings at the front bottom corner. There are openings in the upper middle area of both S4 and S5, but remember to select speakers that aren't too deep, and do not interfere with the windows. You'll also have to fab brackets.

Also, the rear speakers have a single amp inside each enclosure, just cut the speaker leads from the two prong connector on the bottom of the enclosure and connect directly to the speaker.

The front speakers may be sounding bad because of that factory amp (either fried or just overloaded by the output from the Alpine receiver), so be sure to bypass them.

 

if it were the factory amp that was blown wouldn't the other speaker sound crappy too? its just my right front speaker that is receiving a lot of bass response from my receiver...what should i do?

 

Bypass the factory amp, directly connecting that speaker to the headunit.

If you're still getting only bass, try swapping speakers and see if it's the speaker that's bad (could be a blown tweeter if it is).

 

Also...

It could be only one of the two channels of the factory amp is bad. As I explained before, each factory speaker has its own amp, and the box in the front has a two channel amp, but I think the circuitry for each channel is separate. So, if one blew, the other may still be fine.

Regardless, if that test of swapping speakers gave the same result--crappy sound in the right channel, it's the amps.

Bottom line: the factory amps are junk. Bypass them and get rid of them. That alone should make things sound better.