Attached are a couple of snapshots showing a little bit of the installation in my ShoWagon. (That's a Ford Taurus station wagon with a powertrain and interior out of an SHO sedan)
You can't see the in-dash speakers, but there are six of them in the dash. (There were none to start with) They are all flush mounted in the top of the dash and the grilles are painted to match -- practically invisible. We had to remove the windshield to install them. All the front stage speakers (4.5" x 1" separates in the corners, plus a 4"x1" coaxial center channel) are Diamond Audio Hex series speakers.
The 6.5" speakers located high up and forward in the front doors are also Diamond Audio Hex speakers.
The empeg player is placed where the electronic HVAC controls used to be; the HVAC controls are now where the cupholder/cointray used to be. The cupholder/cointray is now in a cardboard box in my spare bedroom.
The CD player is a high-end Clarion -- HX-D10, I think it was, with pre-amp outs only, no internal amplifier. The empeg and the clarion run into a Sony XA-39-II switch before feeding a pair of Audio Control EQT 30-band third-octave equalizers (one for each channel). The subwoofers are driven by an MTX 8302 amplifier running 4-ohm bridged mono. The rest of the speakers (6 dash speakers, two door speakers, and a pair of Boston Acoustic pro-series way in the back, up in the roof) are run by an a/d/s 850MX amplifier, which (because it has some serious problems and has to go to New York to see the amplifier doctor) will be replaced next week by an a/d/s P850 eight-channel amplifier.
There are remote gain controls located in the center armrest for the subwoofers and for the center channel. If you lay your arm on the armrest, your fingertips will be on the controls.
You can see from the pictures that the installation is pretty much stealth (my apologies for the stains in the carpet courtesy of the previous owner of the car -- no detail shop has been able to remove them so I will have to have that carpeting replaced). But, as I start opening up storage doors and removing trim panels, some of the stuff begins to see the light of day. If you grab that handle on the aluminum diamond-plate amplifier rack and lift it up (hinges on the front of the rack) you get access to the spare tire, jack, jumper cables, tools, fire extinguisher, first aid kit, etc. I am very proud that no compromise to the utility of the vehicle was made for this installation, other than replacing the full-sized spare tire with a space-saver spare to make room for the amplifiers and other components on the amp rack.
With the combination of the gain controls (four of them on the P850; two on the 8302 (only one functional because output is bridged mono); remote center channel control and remote subwoofer gain control); plus the balance and the fade control on the empeg, I can literally send 100% of the output to any single speaker in the car, or any combination thereof (counting the in-dash 4.5"x1" separates as a single speaker, of course). This allows me to do Very Good Things (tm) with imaging and staging, and with the combination of the two EQT equalizers plus the equalizer built into the empeg, I think I'll be able to get it sounding the way I want it to sound. Haven't worked on the equalization yet, though -- the installation is still a work in progress, and we haven't had a chance to sit down with an RTA and really work it over.
It's strictly a Sound Quality car, not a boomer. I think it will probably reach about 125--130dB maximum. It is the third serious stereo car I have built (well, that I have had my stereo shop build for me!) and so far it would appear that on a scale of 1-10, the first car was an 8, the second one a 6.5, and this one is a10.