Miata Mailing List: April 1995, Message #185
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   From: "cory.j.hoeglund" 
Subject: Stereo Adventures, Long Message
   Date: Tue, 4 Apr 1995 17:14:43 -0400

I finally finished installing my receiver, speakers, and amps in my Miata.  I 
thought this might be interesting to some of you out there.

I used the mounting kit supplied by Crutchfield for my receiver.  IMHO it looks 
pretty good in the dash, although I wouldn't call it a *factory* finish.  One 
nice thing about the Crutchfield kit is that the mounting bracket is one piece 
and metal, so I was able to make a bracket out of some metal strapping to 
secure the back of the receiver to the bottom of the mounting bracket.  (A 
little extra security to slow down a would-be thief.)  :-)  The only minor 
trouble I had in installing the receiver was getting the center section of the 
dash panel back in place.  The trim around the perimeter of the receiver's face 
stuck out a bit which made for a tight fit when I tried to re-install the 
panel.  Once I cleared the receiver's face trim, however, everything snapped 
into place and looks fine.

I installed Boston Accoustics Rally series components in the doors.  This was a 
serious challenge.  The 5.25 inch woofers went into the factory mounts very 
easily (using mounting adapters from Crutchfield), but putting the tweeters in 
the doors got my blood pressure up.

After considering various mounting locations (doors, dash, A-pillars) for the 
tweeters, I decided to do a flush mounting in the same location that the Mazda 
Sensory Sound System's tweeters are located.  I wanted the look of a flush 
mount, and I liked the location on the top of the door panel, aligned with the 
vertical edge of the triangular window.  I measured carefully for depth, and 
decided to forge ahead when it looked like it would be close.  I measured again 
(My dad always said "measure twice, cut once"), then trimmed away the fabric in 
the door panel and cut 1.5" holes using a hole saw.  The tweeters went in and 
looked fantastic.  I remounted the door panel and to my dismay, there was not 
enough clearance and the tweeters stuck out about 1/8".

This is where it gets really interesting.  I REALLY wanted a perfect fit so I 
decided to make some depth.  I drilled hole around the perimeter of my cut-out, 
then took out the trusty sabre saw and hacked away at the door.  BEWARE this is 
a dangerous maneuver and should be done with great care.  My tweeter mounting 
was centered over a 1" bolt-access hole in the top of the door.  I expanded the 
bolt-access hole, turning it into a 1" by 2.5" rectangle.  The cutting was 
tricky and it was necessary to bolt a block of wood to the bottom of my sabre 
saw to avoid blade interference with the inner portion of the door panel, but 
it worked out great, and now my flush-mounted tweeters are flush.

The cross-overs for the speaker components were another challenge.  Be prepared 
to spend some time with your head under the dash and your feet in the air for 
this part.  I put one cross-over on the driver's side behind the fuse box and 
the other one on the passenger side at the top of the foot well.  The toughest 
part here was getting the drill in behind the fuse box to mount the 
driver's-side cross-over.  Once I removed the fuse box and disconnected some 
wiring, it wasn't so bad except for all of the blood rushing to my head.

Another challenge was pulling wires through the doors and into the cockpit.  I 
used a coat hanger to thread them through.  The tough part is finding the end 
of the coat hanger under the dash.  There are small openings, one behind the 
fuse box on the driver's side, and one under the glove compartment.  These are 
the openings that the wires will thread through.  It's not as easy as it might 
seem at first glance, but it works.

I put 3.5" Pioneer speakers in my headrests.  I would highly recommend these, 
and if you already have wiring in the headrests, you'll save $30 over 
Clearwater.  I chose to re-wire the seats to avoid the Mazda wiring's high-pass 
cross-over for the factory headrests (94 and later models).  This was easy with 
the use of a coat hanger.  I also removed the seats which helped me gain 
access, but would be necessary if you were only changing headrest speakers.

I ran all of my wiring into the trunk through the opening in the passenger 
side.  You'll see a couple of other wiring bundles in this location if you 
remove the carpet behind the seats.  I used the existing wiring channels under 
the carpet on both the driver and passenger side for running speaker wire from 
under the dash to the back of the cockpit.  (The door sill moldings and kick 
panels under the dash need to be removed to do this.)  I ran my audio cable, 
receiver ground and amp-turn-on lead under the center console, taking care to 
spearate the ground and turn-on leads from the audio cable.

Once in the trunk, the whole installation was pretty easy.  I installed two 
amps, one for the headrests and one for the door components.  The headrest amp 
is mounted in the little nook behind the spare tire, and the door amp is 
mounted inside the spare tire.  In both cases, I mounted the amp to a piece of 
plywood before installing them in their final location.  Wiring for the amps 
was pretty easy.  I ran power directly from the + terminal on the battery, with 
in-line fuses at the battery side for protection.  I ran ground cables from 
mounting bolts near the battery, and I ran my turn-on lead to one amp and 
tapped into the same lead for the other amp.  No problems.

Now that its over, I can say that it was more work than I thought it would be.  
However, I should add that I enjoy projects such as this one, and I'm confident 
that I did a better job and was more careful than the *pros* at the electronics 
store would have been.  Besides, the whole new system sounds awesome!  Here are 
some tips and lessons learned:
1.  Take your time, be patient and be careful.
2.  Use solder to splice wires, especially speaker wires, and use good crimp 
connectors for speaker, amp, power, ground, etc. connections.
3.  Don't let the guy at the audio store sell you $50 gold plated fuse holders 
unless you're powering a one giga-watt amp and you need the fancy looks of gold 
plating on components nobody ever sees.
4.  Get a good coat hanger and some duct tape before you start.  They make a 
great system for pulling wires.
5.  Stock up on blades for your sabre saw before you start cutting.  (I made a 
quick run to Target to buy some in the middle of my project and got rear-ended 
by a guy in a mini-van on my way home.  Fortunately, I was driving my truck, 
but I still sustained $1200 in damage.)

Good luck on your stereo adventures.

Cory
94 Laguna Blue A, wired for sound.

P.S. Maybe someone can help me name my car based on this experience?