Flash forward six months, the Miata project picks back up and I'm down to just a set of 6.5's in the door. No source unit, no rear fill, no tunes. Not optimal.
After a little research, I decided to use my Droid X as the source unit. The car dock was cheap, it's easy to get signal out of it and there are some nice Car Home replacement applications that provide an easy to use interface. It also gave me things like navigation and internet access for just the price of the car dock.
There are a few design considerations that needed to be accounted for:
- Volume control - the phones controls were not that easy to adjust without looking at the device
- Ease of access - The phone needed to be close enough to be used with my right hand near the shift lever
- Sound adjustment - Figured this out during version 1.0 of the system, the phone has no built in EQ
- Vibration - Another 1.0 bug, the suction cup mount on the car dock allowed the phone to vibrate, a lot
- Bass - Wanted more then I was getting, needed to figure out how to add the subs without adding lots of weight
- Power control - Needed to be able to turn off any of the devices (including voltmeter)
- Cosmetics - It isn't a show car but the end result needed to be decent, no ugly box, no hole in dash
List of components:
- Pioneer 6.5 full range speakers (doors, came with the car)
- Polk 6.5 components (left over from another project)
- Planet Audio Anarchy amplifier
- PAC LC1 remote volume control
- Cheap 8" subs (they're good, but not name brand)
- Pyramid 709EX EQ (decent but get a better one, very susceptible to engine whine)
- 1/2" MDF
- Black carpet
- Various screws, wires, fuze blocks, connectors, etc (left over from other projects).
- Stinger voltmeter (looks cool, left over from another project)
- 3 large switches (1.0 switches were smaller, felt cheap, were hard to toggle, got bigger ones, added covers)
As you can see, I was trying not to break the bank with this install. I wanted decent sound but, with as much road noise as you get in a Miata, audiophile level gear would have been wasted (and not really in the spirit of this project).
Here's the final layout:
Not an overly complicated system. The hard part was going to be fitting the subwoofers, amplifier, EQ and components in the location formerly taken by the top (wanted to keep the weight in the middle of the car).
It took a few tries but, eventually, I figured out a cabinet design that would work and allow the speakers about a cubic foot each. That, and some poly fill, would allow for enough air movement for decent sound and still fit into the limited area I had to work with.
The fill panel for the dash board was created out of a sheet of ABS and screwed to the stock mounting points on the backside of the console (I also added some side supports since the panel would get some pressure applied to the bottom corner when the switches were flipped). Switches, from left to right, are amp/EQ power, voltmeter power, phone power (the "jet fighter" covers are just for fun). Originally, there were three, much smaller, switches but they just didn't feel right and were easy to miss in the dark.
To get the PAC adapter mounted was mounted by removing the main housing, running the adapter through the ABS panel, then securing the main body back in place on the other side.
The next challenge was the phone dock (and I ended up zapping my X during this build and had to go get an X2, win?) It had been mounted on the windshield but it vibrated so much I was worried it would damage the phone.
After looking around a bit, I came up with the idea of mounting it next to the console but wasn't, initially, sure how to do it.
After some failed attempts, I took a look at the small map light mounted in the dashboard. It hadn't worked in years and it looked about the right size to re-purpose as a mount.
So that's exactly what I did. I took removed the wiring harness, dremeled a large hole through the map light, then took the dock apart and ran the base through the hole, securing it with a zip-tie (around the shaft of the base) on the other side.
It's not perfect, and is at the top of the list of parts to get replaced (the dock tends to rotate a bit), but works well for now.
The final part of the build was the speaker cabinet/amp rack. This was a pain to build (I know, looks simple, right?), I wasted a bunch of wood experimenting (though I never used up my initial supply) but, in the end, it looks exactly like my first sketches.
Once everything was back together, I had knocked everything off my initial list but came up with a few new issues:- Engine whine, the EQ has it - Everything is grounded together and they all run back to the battery but, for some reason, if I turn the power on to the phone (or even plug the charger into the phone with the switch off), I get whine. This didn't happen before the EQ and I think I can solve it with an inline noise reducer
- Dock likes to pivot around in it's mount - As mentioned above, this isn't a huge problem and is pretty easy to solve. I'm going to make a custom mount to replace what's left of the map light, remove the base of the dock, and mount the remaining parts to the new mount. This should give a solid foundation for the phone and fix this problem
- Remote gain control for amp not mounted - This is an easy fix, just haven't gotten around to it
- Subs need grills - Just need to order them
The end result was worth the trouble. The stereo is easy to hear on the highway (even at 80+ with the windows down), the little subs have plenty of punch for the little car and everything is easy to get to. The over-sized controls make it easy to use without ever taking your eyes off the road and the few pieces someone would want to steal are buried in the back (the seats have to be removed to get the box out) and bolted to the studs used to hold the top in. It's fun, mostly secure and fun to play with though not perfect. Sounds perfect for a project Miata, no?
