From: pbern@next.com
Newsgroups: rec.audio.car
Subject: Story: Upgrading an Integra
Keywords: subwoofer, acura, upgrade
Date: 6 Apr 92 20:35:32 GMT


I "upgraded" the stereo in my '88 Acura Integra and thought I might detail it  
for this news group.

The idea was to upgrade the stereo in a "step" fashion that didn't break the  
bank all at once but would allow me to make incremental improvements. I should  
note that the majority of music I listen to is CD which is sourced from a  
discman, into the cassette drive via the Recoton cassete interface.

The first step was to improve the highend response because the drivers that  
came with the car were basically garbage.  What I did was replace the drivers  
in the front doors with Alpine 5.25" drivers (I forget the model number).  This  
improved both the high end and low end considerably.   I then took the 5.25"  
drivers that were in the front and put them in the back since the back drivers  
were fullrange/wizzer-cone drivers, and the old fronts are coaxial.  

This was pretty good but I had to crank the bass up all they way to get an OK  
low end.  This of course stole alot of power from the system and I couldn't  
crank it that much else distortion moved in.  I figured the next step was a  
subwoofer.  

I decided to build a subwoofer cabinet for the car, as apposed to buying one,  
to save money and to "custom fit" it for the car.  I ended up building a  
"wedge" shaped cabinet that fit the back of the car and would still allow me to  
put the rear seats down and do some "light hauling".  I also wanted to make it  
removeable so it did not have to "go with the car" when I eventually sell it.   
The cabinet eneded up being about 13" high, 13" deep, and 36" wide.  Interior  
volume was about .8 cubic feet.  I placed one 8" woofer (Radio Shack, $34.95).  

For power, I bought a Sentek (cheap) 250 watt power amp and an alpine  
crossover.  In retrospect I should have bought the alphsonik all-in-one  
poweramp/crossover (especially since I do NOT need 250 watts), but I was new at  
this and wasn't quite sure what I was doing. I tuned the equalizer to crossover  
at about 60 Hz.

I really wanted to drive this with line level, rather than speaker level, but  
the stock acura radio didn't have, line outs...or did it?  The acura radio had  
this plug in the back that had a connector shoved into it.   It turned out  
(after some research and guessing) that it was a "shorting" plug that took the  
line level out, and crossed it back into the power amp inputs of the radio.  It  
was there so you could either add a CD player or an equalizer (sold thru the  
dealer for big $$$).  I bought an 8 pin DIN connector, made it into a shorting  
plug, but brought the line level signals out.  I fed them into a dual volume  
pot (again, Radio Shack),    and fed the signal into the subwoofer equalizer  
inputs.  The volume pot was necessary since the the line level outs of the  
radio were pre-fader, plus I wanted to be able to boost the bass to higher  
levels when on the highway when the road noise was greater.

How did it sound?  Awesome!   I didn't think the RS woofer would make much  
noise but it did a great job.  With the subwoofer in place, I could turn the  
bass way down on the radio, and get all the volume I needed.  The low frequency  
response is unbelievable and very flat.   

The total cost breaks down as follows:

	Cabinet		$ 10
	Sub Driver	  35
	Alpines		 100
	Amp, xover	 215
	wire, etc	  10
	---------------------
	Total		$370
	
The next step is to replace the radio with a good CD unit and that should about  
do it.


Hope this was at least interesting to someone.  If anyone wants more info,  
please feel free to email pbern@next.com