My 1990 Sovereign has the 6 speaker, common ground, 2 speakers under the rear seat configuration. Despite the cars extremely low miles (16xxx) the stereo system sounded dreadful, although everything worked and was original. Once we got into the build it was easy to see why the sound was a bit substandard.... This was one of the speakers under the rear seat, missing most of its rubber.



The mission was similar to the build I did in my Series III. Upgrade the sound. Add bluetooth hands free calling and audio streaming. Make the install as stealth as possible. Make no permanent modifications to the car.

Door speakers : In my sovereign spec car they door speakers were incredibly puny 3.5 inch. I replaced these with 2 way 4 inch Sound Ordinance speakers. It was a bit of a fiddle to get the larger speakers to fit but eventually they did. Removing the door cards was relatively easy thanks to plentiful advice on this forum. The only tricky part was removing the door handle screw access cover. As my car had never been apart before these required a real wack with a drift to get them to come off. Once I did the first one and could see how they were held on it became easier to wack the other ones knowing that I wasn't going to break anything.

Head Unit : I bought the extra surround kit for an ebay seller in the UK. I fitted a pioneer head unit with all the necessary features I was looking for. Removing the stereo is quite easy, again, lots of advice on this forum as well as a really good video on YouTube on how to do it. As the factory stereo connected using those standard big fat round connectors as used throughout the XJ40, there was no way to install a new system without cutting the wires. The entire center stack comes out very easily once you have the ashtray and the skislope removed. This made it easy to work on adding the fascia surround on the bench instead of being inside the car....



Interestingly the original tape deck was considerably deeper than the pioneer stereo I fitted....... the original is at the bottom of the picture and the pioneer is in the stack at the top....



As my car had common grounds for the left front/rear and right front/rear, I decided to wire the speakers together in parallel. This gave me a 2ohm load which the amp was capable of driving. I have never used front / rear fade in any stereo set up I've had, so I reckoned I wasn't losing anything. The alternative would have been to add a ground to each front speaker, but I didn't want to mess with the wire going through the door and into the car.

Amplifier : Unlike the Series III, there is no room under either of the front seats in an XJ40 because of all the electrical parts of the seat. I really didn't want to have to place the amp in the trunk because that is a lot of work, and the trunk is completely stock, so I found an amp that would fit against the firewall in the passenger footwell. I made an acrylic cover to go over the top of the amp to give it about 1/2 inch of breathing space, as defined in the instruction manual. Once the carpet is back in you can't tell it's there. This picture is without the acrylic cover in place....



Under rear seat bass speakers : These are 4 inch. The plastic covers just prise off then 4 screws frees the speaker. I replaced these with 1 way 4 inch speakers with 1 inch travel in the hope that with the amp driving them I would be able to get some bass from them. These speakers used the original car wiring and were powered through the 2nd channel of the amp while the 1st channel was driving the door speakers.

Stereo in place. Variable color illumination allows it to blend in with the rest of the car.



I had this set up running for about a week but I just couldn't get happy with the sound quality. By the time I had enough low frequency, the poor little 4 inch speakers under the rear seat were crying in pain. I knew there was little point trying to add bass into the trunk as the trunk to cabin is practically airtight. I did not want to cut/modify/add anything on my pristine rear parcel shelf........ I knew the best way to get self contained bass as I had used this Clarion 6.5 inch powered subwoofer in the Series III and also in the XJS.


The challenge was where to put it........... eventually I came up with something..... see if it jumps out at you in this pic.......



Yes, that's it under the center arm rest ! It is easily removable for the extremely rare case when I have 5 people in the car.

Conclusion : Really full sound, all the features I wanted, minimal (stereo wiring loom cut only) disruption to the car

 

I thought you didn't like to listen to the radio....See Sig


Nice work. I replaced the head unit in my 94 also buying a surround from the UK. Fortunately the 8 speakers sounded fine so everything else was left stock.