I didn't want a plasticky new-fashioned CD player uglying up the dash and encouraging theft where there's currently a period radio, so the plan was a little more involved. I wanted to fit an amplifier somewhere hidden, speakers in the doors, and tweeters up front on the windscreen surround. The amp would end in a 3.5mm adapter, ready for an MP3 player to provide the source.
After much research, I went for some JBL kit which seemed a nice compromise of features and cost:
- GTO75.2 amp - 145 watt into 2 ohm, 2 channels, eBuyer quickfind 130988
- GTO507C 5-1/4" component speakers - mid-range and tweeters, eBuyer quickfind 130985
- InPhase amp kit to fit everything together, eBuyer quickfind 118167
Next day when the thing arrived, I realised I should have researched a good bit more. It's huge and there's no chance of it going under the rear seat. The much-scratched head eventually told me to fit it in the boot, screwed upside-down to the rear parcel shelf, and that's where it went.
It was a lengthy job. All the seats and carpet came out and there was drilling and gromit-fitting needed to route the cables discretely. There's a lot of cable to route in this setup - a hefty power cable goes directly from the battery, through a 30amp fuse into the +12V on the amp:
As there's no head unit to connect to, the "REM" connection on the amp goes to the fuse box via a switch I tucked in under the dash. This is just used to turn the amp on or off and is a much lower rated (5A) cable:
Earth for the amp comes from a hole in the parcel shelf, filed to the bare metal and smeared with Vaseline (inhibits water, conducts electricty, the mechanic's friend).
Then there's speaker cable from the amp into the door where it meets the crossover for the speakers. From there into the door speaker and back through the hinge up to dash for the tweeter. I was without camera for the job, so all we have here are the end results where you can just see some cables taped to the hinge:
(they're safer and more secure than they look).
Fixing the amp to the underside of the parcelshelf proved difficult. Being upside-down in the boot with a drill isn't easy and after much squeezing and twisting and drilling the amp finally revealed that it wasn't going to fit. Two bolts secured it nicely at the back, but then it stuck out too much at the front to bolt it in.
I'd stuck the speaker crossovers (small, light plastic boxes about 6 inches by 4) to the inside of the door panel using heavyweight Velcro, so I tried the same with the amp. To my surprise it held very well, and I bolted it at the back and left it in place. After one particularly hot day the glue holding the velcro strips to the parcel shelf gave way and left the amp hanging... Currently there are cable ties holding it at the front while I think of a new plan:
With the amp and cables in place, the rest wasn't too hard. Taking the door panels off is reasonably straightforward (careful application of a steak knife will release the circlips holding the door release and window winder), and the 5 1/4" speaker fits nicely underneath and to the rear of the door handle:
Note that the gap in the door panel at this point won't really allow for a larger speaker, and you need to be careful with positioning. Too far towards the rear of the car and the powerful magnet in the speaker will attract the chain of the winding mechanism, which will stop you lowering the window.
Top tip: putting the circlip for the window and door handle back on is a much trickier business than removal. I found you can fit the circlip in place on the handle (it'll go about halfway home), push the handle on as far as it will go and slide a credit card up to the circlip. A small nudge will push it into place and save you hours of grief. God knows how the factory boys managed it before the Age of Credit.
I'd intended to drill out the windscreen surrounds to fit the tweeters flush, but this would have been a close call requiring some precision drilling. For the moment I've fixed them on top of the surround (with double-sided tape), with small holes taking the cables away unseen. This looks okay and will do for the time being, although I'd like to sink them properly at some point.
The amp comes with a few settings you can twiddle to set the sensitivity of the source and beef up the bass response. A little tweaking was needed and one speaker had to come out to have its connections tightened, but once in place the setup sounded great.
A job that took the best part of four days in all, although that included some thorough cleaning of seats and carpets and a minor service. I'm very happy with the result though, which sounds clear and detailed. Just need to reduce the road noise...
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