Home | Mailing List | Specifications | Care and Feeding | Modifications | Vendors | Literature

Factory Sound Systems and Modification

By Tim Wright, Gary Smith and Mike Ivy

Factory Sound Systems

It seems as though Ford began cutting costs as soon as the 96 model year came to an end.  The first of these cost cutting measures was directed at the sound systems in our cars.  In 1996 the SHO was available with a JBL sound system.  It featured 7 speakers, trunk mounted 6 disk CD changer, integrated amplifier/AM/FM receiver and a power antenna.  The JBL system required the Automatic Climate Control.  For the 1997 model year Ford decided to only offer the "MACH" series systems in the form of the MACH 80.  It featured only 6 speakers (no subwoofer) in the same locations as the JBL system and could be had with a trunk mounted 6 disk CD changer as an option.  The MACH system also required the Automatic Climate Control and until the 99 model year it featured a power antenna.

The following images are to show the differences between the Gen III SHO (1996) Ford factory installed JBL audio system, and the Ford factory installed `Premium Sound' (also known as the MACH 80) audio system used in the 1997 - 1999 SHO's, by way of displaying the different speaker compliments used....


1996 JBL System Components click any image for a larger version
Lets start our tour with the rear deck.
Here in the 1996 SHO, we can see clearly the JBL 5 x 7" rear left and right speakers and the special JBL 6 x 9" subwoofer...

This image shows a close-up of the rear channel JBL 5 x 7" driver. Note the part number as F6DF18971GA The JBL logo can clearly be seen as well as the gloss black paint used on the basket frame.
This image shows the JBL 6 x 9" Subwoofer, note the crossover case mounted to the back plate of the magnet structure. The part number reads: F6DF18C804AC
The 1996 JBL Amplifier/Radio can be seen in this photo, the JBL logo is on the front face where all the plugs are attached, and also on a simple tag on the lower right of the top cover as seen.
Moving to the front of the 1996, we see in this photo the 5 x 7" bass driver in the left door. DO note the crossover mounted to a plate associated with the speaker connector plug on the opposite end. The cross over in this JBL speaker cuts out any high frequencies that would result from running this FULL RANGE... By design, this driver is made to act as a bass speaker, leaving the driver in the `sail' cabinet to play lower also, adding more presence at ear level and thus a better stereo sound stage/image.

The JBL logo is clearly seen here and the part number is: F6DF18971HB
This is a head on image of the left hand JBL `Midrange/Tweeter' driver mounted in the sail cabinet..

Note the fiber 'dustcover ' on this driver and the foam seal just to the left to couple the cabinet to the panel behind the outside mirror. You can also see the bracket used to hold the grill in place.
1997-99 Mach 80 System Components  
This photo gives you a view of the Ford Premium Sound 5 x 7" drivers in the rear deck for 97-99.  Since the JBL system was dropped in exchange for the Premium sound system, there is the absence of the JBL subwoofer. Note the now empty cutout for this missing driver!

You can directly compare this and the other 1997 - 1999 photos with 1996 images found above.
Moving to the front of the 1997-99 SHO, the photo shows the Ford Premium Sound 5 x 7" speaker used . Note that there is NO crossover used in this setup, as the driver is running in `full range' mode, and the upper frequencies delivered by this driver in its design, are a desired effect to blend with the tweeter mounted in the sail cabinet which starts life at a higher frequency then the JBL counter part used in the 1996 model.
The 1997 Premium Sound Midrange/Tweeter is pictured here. This small driver is of the `dynamic' construction, meaning, a paper cone midrange WITH a cloth surround, the tweeter portion is the plastic `hard dome' in the center. Because the 5 x 7" bass driver in the door has no crossover, this small driver doesn't need to play as low as the tweeter unit in the JBL system used in the 1996 SHO. Note the PLASTIC grill covering this driver. If you look carefully, you will see the `high pass' crossover filter used inline with the wiring harness just below the sail cabinet. It is wrapped in a foam envelope to keep it from vibrating against the door frame..
If you ever have to replace a speaker...  
This front and rear photo shows the NEW Premium Sound replacement 5 x 7" bass speaker for the front door.

This rear shot shows an interesting fact, and that is the use of a capacitor/crossover seen here at the bottom of the driver! This seems to be the new FORD replacement speaker used when 1996 owners have a blown JBL driver ! To make this speaker work in the 1997-99 Premium Sound system, you must JUMPER the cap out of the circuit and this will cause the driver to run `full range' and match the ORIGINAL Premium Sound 5 x 7"...

If you have a 1996 JBL system, just use this driver as is and it will match the bass cutoff frequency needed to for that situation. Part # F6DF18971-FC (Premium, just like the ink stamp on the magnet shows)

Modifying the Factory Sound Systems

If you have a 96 or 97 without electronic temperature control do not you have the Mach or JBL system.  A kit is available from Crutchfield and others to mount DIN dash units in the car. You have a good start.

Otherwise for any SHO with electronic temperature control, no such kit exists.  Behind the integrated oval that holds the controls for both the climate control and sound system, little exists except push button controls.  The actual "dash unit" is in the trunk.  Because you can not change the dash, you can't change the "dash unit" unless you just want to leave it there and ignore it and put in your own system some how else.

The Mach system is rated at 80w; maybe we can just change out the factory speakers? I wasted a lot of time on this plan. Replacement speakers need to fit the factory opening, not have so much "throw" that they require mounting depth that does not exist, and sound better than the factory speakers. The factory speakers are a less than popular cut out size, when you look at quality speakers they tend to have a fair bit of throw and require more depth than is available. After looking at a lot of high end and middle quality speakers I never found anything that would fit much less improve sound quality.

The head unit and power amp, both located in the trunk do not have pre outs or even outputs suitable to feed quality power amps so you can run your own amps and speakers. Ford really did a job making it unmodifiable.

So can we do?  Use the Dolby setting when playing tapes and using the loudness compensation which increases base and treble and helps just a touch to make the system livable but not remarkable.


  Contact Information