waltz

I finally finished my full upgrade in between enjoying the Xmas Holiday, relative visiting, and culinary

distractions :D

I am offering these tips to folks that may be doing this that might find it helpful as many of the custom things I did were trial and error! :rolleyes:
This is long - but so was the project! If you plan on doing it yourself I really believe you may find some helpful pointers here - I wish I knew all this before I started!

These info pertains to my '99 Convertible that had the stock CD Bose system with change to start - your mileage may vary in FRCs or Coupes.

Some of my key requirements were good 8" subs up front and a long, more rectangular 5 channel amp for the back as I did not want to fill my rear compartment as many folks have done. I also went with an MP3/WMA HU with AUX in to support expansion for a Neo Jukebox latter (Can you say serious gobs of tunes? :crazy:

Front Speakers

MDF is the way to go for re-doing the stock speaker mounts. I used 3/4" from Home Depot (had to buy a full 4x8 sheet which provided plenty of practice room for me and the ole jigsaw :D ). I started with the stock speaker mounts (plastic with a compartment behind the 3.5 stock speaker for the Bose subwoofer amp) to make a basic template. I would *not* recommend using the stock mounts as they are thin, the amp compartment restricts the use of better speakers, and the 8" hole is too small for "real" subwoofers.

I used 4" full range and full 8" subs as replacements. Note that my subs are 4" mount depth, 7 3/16 openings and almost 8.25" max outside diameter and that they do indeed fit! It took quite a bit of time to finagle them to fit the stock openings and be in the basic pattern of the original template. I ended up widening the holes in the doors for the sub openings all the way out to the mount clips to add extra room. The 4" speakers will fit in the stock hole (square - where the stock amp compartment slides in).

The hardest part for me was getting the two speakers 4" and 8" sub on the template as tight as possible while still retaining all the speaker mount points. This required me to literally have the two right next to each other and as
I also used XTC baffles for both of these speakers I had to do custom sanding and sweating to get them to fit right :mad . Note that you will definitely need to countersink most of your MDF mount points and use longer hardware screws so that the outside rim of the speakers can overlap the speaker plate mounts.

Also note there is plenty of room for a crossover mounted at about 2-3 O'clock off the 4" speaker as I needed. I tied it to the stock wire bundle where the stock connector for the original Bose system is. My passive crossovers were about 3" x 1" x 3/4" blocks.

The area to be most concerned about for fitting the inner door covering back on is at the 4-5 O'clock point on the subwoofer where it gets *very* close to the white plastic grommet and pin :eek: . I had to shave the MDF down at this point as well as the plastic mount on the inner door panel to get them to be happy and squeeze past - let's just say some extra effort was needed. :rolleyes:

Rear Speakers

The Vert/FRC use standard 5.25 POS Bose speakers (Coupe has 6.5). In my setup I used full range speakers - also with separate passive cross-overs. There is plenty of room for aftermarket 5.25 speakers even with oversized magnets and using XTC baffles like I did. There is also plenty of room for mounting/hiding the cross-overs. The rears I used had positional tweeters which had a better effect :yesnod: than I expected - I would recommend getting rears with this feature if possible.

Wiring

I wired the amp using 4 gauge wire - lotso fun to work with :mad. It took almost a full 20 feet to get to the battery. I would recommend getting some type of side mount post to attach to the battery with the stock connector. I ended up chewing mine up to slip the O-ring crimp-on that I used on the wire end. I mounted my 80 amp waterproof AUE fuse holder right in front of the hood latch on the inside wall. The connection from the fuseholder
to battery was tight (twisting 4 gauge wire in tights spots is a PITA!) but the fuse is easily excessible and cool to see :D . Go through the firewall using the rubber grommet location that is behind the battery and about 2-3" down - it has a rubber panel covering it inside the car. I simply drilled a decent size hole right on the edge of the opening and ran my 4 gauge power next to the stock wire bundle that is almost 1" diameter.

For grounding the amp I was really at a loss to get a nice, close, chassis ground from the amp in the back until I started snooping around the space between the inner fiberglass tub of the car and the outside panel. There
is an amazing amount of space here for the rear chassis member and the foam cushion for the rear "bumper". Make sure not to lose any tools back here - there are plenty of holes to drop them in - especially behind the rear
license plate :mad . What I found on the right side of the car near the power antenna (sorry coupe folks - not sure if you have this) was a wonderful, thick ground strap from the antenna running to a stock bolt onto the rear cross
member - perfect for ground!

The other trick that I found handy was setting up the ends of the power and ground to plug into the Weco connector for the amp which was only big enough for about 10 gauge wire. I ended up buying some gold plated RCA jacks from Trash Shack with the banana plug connectors that have a threaded barrel. They are only intended for 12 Gauge but "have drill and vise" and I bored them out to over 6 gauge leaving the threads intact. A couple of 1/8" holes on the side of the barrel for poring in some solder and I had some wonderful, strong, clean connections.

As I wanted to make sure I did not get any noise, I ran my power down the right side of the car, speaker cables down the left, and RCA cables (3 pair for front/rear/subs) along the right only to the "C" pillar behind the rear speakers where I cut into the middle, over the passenger side hump behind their seat and to the middle tunnel where the console is. I used 16' RCA cables but I would have been safe with 10-12'. I hid the excess under the carpet behind the passenger seat. Note that the rear corner panels in the Vert are pretty snug up against the rear tub of the car so I cheated by running my fatter power and RCA cables through a hole in the tub near the amp and then "popped" back inside once I got to the rear right corner where they would not interfere with reinstall of the corner panel.

The hardest part of running the cables was removing all the trim and carpeting. I labeled smaller pieces as needed to insure I got them back in in the correct way. Some of the corner carpeting pieces in the Vert are pretty weird shapes and not symmetrical side to side. You must remove the top seatbelt mount nuts to get all the trim off.

The trim pieces along the doors are SOB tight :smash: but just carefull pry and find the friction fit snaps and concentrate on them to get them off. Starting from front to back on the long piece along the door sill seemed to work best. Watch out for the metal edge :eek: that is exposed once the trim for the outside door edge (that the seat belt winds thru) is off. It is rough and quite sharp in some places. There is plenty of room to run cables on the sides I just used plastic ties and industrial grade packing tape to keep things clean on my runs.

Getting the wires into the doors was easy by removing the rubber panel inside the car up against the outside wall and then using a stiffer fish line wire to pull the bundles through. I ran all my wiring just in doubled over
pairs and only cut them off when I got to their final place. You can short pairs easily with a helper and check continuity to determine which are what later.

I ended up removing both the underside kick panels in the foot panels and the entire glove box assembly to do what I wanted and to run the wires clean. The driver side panel was a MAJOR PITA :mad to remove for me as it has a friction locking washer on a steel post all the way back above the clutch pedal. I could only get to it by doing the mambo on my back and pushing all the way underneath to pry the bastard off. When swearing loudly :cuss about this my wife suggested that the General uses a lock washer here rather than just the annoying plastic "pins" to insure that this panel stays in place and does not interfere with the driver's feet. Plausible reason! And I am the engineer! :D


Removing the glove box is no happy task either :crazy: . Someone was sleeping on this design for sure also as it takes one bolt on the right side, 4 on the top edge and two at the inner hinge to remove. The only way to get to the last two is to pop out the PITA plastic caps about the size of a quarter on the bottom of the glove box. Yup - that's what they are - the mystery is solved!:rolleyes: Force the door open past its extreme by bending in the side panels until the door swings down just enough to allow you to get a ratchet with an extension on the turkies! Once the glove box is out of the way you can thread a bundle of wires through the metal frame of the dash behind the passenger airbag. Make sure to do this with your wires not bundled by anything that will catch as it is easy for the wires to get snagged.

Amp Install

I used a refurbished Infinity amp that fit the bill perfectly for the size and features I wanted and also at a sweet price. It is the discontinued 255a and can be had from Ike's Sound off Ebay for $233!!! It has 50Wx4 ab-class and 200Wx1 d-class for subs in a 23" x 2 3/16" x 8.5" package. Some of the goodies it includes are Weco connectors for easier install, Hi/Lo/flat filters, two band crossovers, and even Q and Frequency filter settings for the subwoofer channel. Most amps are more square and would have required using the center compartment. This amp and a Clarion unit were the only 5 channel amps I could find that were 8.5" or less in width.

I ended up using 4 moly bolts with the long threaded machine bolts to go through the back fiberglass panel of the car to mount the amp on a 5" wide MDF panel directly below the rear trunk hatch. I still had to cut the rear carpetted panel as well as the rear compartment cover (it butts up against the bottom edge of the amp) to get it to fit but it looks sweet and is out of the way of luggage, with excellent open air cooling, and almost no loss
of storage. It also looks great when the amp is on as the amp has a large almost 2"x2" multicolored LED array that lights up when on. Looks like the nuclear fusion reactor in the back! :cool: If you want pix - email me and I
will send you them when I get the chance.

Note that I removed the rear trunk latch mechanism originally when scheming on mounting options and whether I might need to trim this metal piece to get the amp to fit. Two suggestions: 1) You can't likely trim this piece as it
will lose its structural integrity as it depends on the bottom for its strength. 2) mark the original position of the bolts behind this mechanism before you remove them. I did not do this and got to spend an hour fooling around
to get the rear trunk lid to align properly. I am still not completely happy with it but I am convinced it is as good as it was before I started! Also note that GM used some rubber grommets around the washers on these bolts that literally disintegrated when I removed them - I did not replace them - I expect they may have been just for extra cushioning from the force of the trunk being closed? I don't slam my trunk so I am not to worried.

HU install

This ended up being much more difficult to do than I expected. Why? Well with 3 pre-outs on the back of my HU and RCA jacks that require about 1" clearance when plugged in I exceeded the max of about 6.5" depth that you have on the left side. I did not realize this until I had taken the time to remove the original O-mount metal circle that is used with the stock HU to brace its rear. There is not much you can do as the rear panel is the plastic duct work for the HVAC system and although I have heard that you can carefully warm this area and bend it in :eek: - but I did not want to try to do this for .5 to .75" that I needed. I even looked into internally reversing my HU so I could literally flip it over so the pre-amps would be on the right where there is a little extra room. The whole HVAC/HU assembly is oriented towards the driver and there is some extra space due to this angle on the right side.
Unfortunately, this "flip-job" was not possible either but I did get to see the guts of my HU in all its glory! :D

So, unexpected plan B was to swap the HVAC control and the HU positions. I have the auto HVAC control and it is literally a self contained unit with one large connector on the left side and only about 3" deep! Why GM put this
in lower space is a mystery as there is mucho room compared to the top space. The HVAC duct behind the second, lower space collapses into smaller ducts to feed the lower parts of the car here and hence is not the formidable wall like it is for the top spot.

I have seen some folks have moved the HVAC to the bottom space - abandoning their lighter, ash tray unit. Howver, I did not want to do this as. Although not a smoker, I like using the adapter there (I use both it and the console one on the road for laptop and other toys) and the ash tray is the perfect place for the incognito remote radar detector control/display. :cool:

Sooooo, to swap the two took a good amount of trial an error (and I still have some final tweaks to do). One unfortunate must is that the riveted on brackets that the stock HU attaches to must be removed to maintain the same depth using the HVAC on top. I did this with brute force and a pair of bunny nose pliers to pry them off :smash: . I also had to trim the mounting brackets integrated onto the sides of HVAC unit itself to get things to work properly. I eventually cut off the two alignment posts on the back of the HVAC mounting brackets as they were causing more pain then they were worth. I ended up using a level and some on/off trial installs of the center dash console trim piece to see how I was doing. Let's just say I can now install and remove the center console trim piece (which I thought was somewhat awkward when I first did so for my Kirban shifter) with my eyes closed in record time! :D

The other issue you will run into if you attempt this craziness is that your standard single DIN HU with 1.5 DIN trim piece will not work too well with the HVAC on top and the HU below. I ended up with what I thought was the
best compromise. After finagling to get the HVAC to be snug up against the 1.5 DIN trim bracket while still covering the entire front panel holes for both HVAC and HU, I decided I thought it would look better (and work better) to center the HU below and leave a gap between the two. I blocked the 1/4" gap with a trim piece behind and I am now looking into various wild ideas to fill it if I indeed decide to. I nice little blue Neon lite tube? A long thin Corvette logo? A 1/4" blue leather trim piece to match my upcoming shift boot and brake boot? This will be another mini project!

RESULTS:cheers:

In a word - awesome! This project was much more difficult and time consuming than I expected but the results are well worth it.

It took some time to tailor the subs to my taste using the amps adjustments and then finalizing with the door covers back on (this indeed makes a difference as even though the subs are "infinite baffle" or "free air" in the doors, GM did a good job of sealing the doors on the inside and once the top opening gets closed more with the cover the bass gets even more solid. I used Paula Abdul and Bach's Tocatta and Fugue to tweak mine! :D

I now have serious bass with no loss of space - plus with the Roadster I think the up front bass is likely a better match for the open air environment.

The highs are also now clearly present and vastly improved over the stock system. I have a wide and eclectic music taste and after some serious test time with a variety of CDs and MP3s I am extremely pleased with the setup. This started as a project to just replace the HU but rapidly became the full replacement I have babbled about here and I am glad I went for it!

Next step is the Neo Jukebox MP3 player so me and 5000 CDs can hit the road on one of my long road trips. Don't let anyone talk you out of looking at MP3s for a great way of getting huge amounts of tunes on one CD (or in the Neo a hard disk) - it is the way to go and supported by almost every HU vendor. I have seen posts to the contrary but I think these folks are spending too much time on the CF and not looking at the rest of the Internet. MP3s are going to be around for quite awhile and the HU I got also does WMAs if I want even more compression. Finally - if you think Napster's death ended MP3s U surely have not checked out any of the clones. I don't condone stealing music :nono: (I have almost 1000 CD's) but I do like to download and check out all kinds of music before I plunk down my hard earned cash for music "I cannot return".

I hope this helps - please feel free to email me for any questions on my rambling - I would be more than happy to help anyone else in taking on a similar audio endeavor. :seeya

Wicked C5

Your setup is real simler to mine. :cool:

lotzahp

"A picture is worth a thousand words" - literally in this case :) Sounds cool, but let's see some pix!