Car stereo 1: Fiat Marea Weekend
In May, 2003, I bought this Fiat Marea Weekend 1.6ELX, replacing the Fiat Uno 75SX I had been driving for 5 years. The little Uno, although swift and peppy with its 75 hp, was a petrol hog, and with petrol prices steadily rising in this part of the world, I chose to buy a car that ran on LPG (Liquified Petrol Gas). LPG is less than half the price of petrol, while you pay only a very small extra tax for the LPG installation. A used car has its break-even point as low as 2,500 miles or thereabouts.
In the Uno, there wasn't enough room to fit an amplifier and a subwoofer. I tried some setups with a speaker cabinet under the front seat, but it never really took off, so to speak. So I stuck with the speakers in the back and a standard radio. A large amplifier brick and a subwoofer in the trunk would've taken damage during vacation or during transport of stage equipment.
The Marea, however, is a pretty large estate (4.49 m) with room to spare. In the back, the seats can be folded up towards the front, while the backrest folds down to make a flat loading space. Because of this, there's room underneith the back seat with easy acces, while in normal use it'll never be exposed. Perfect for an amplifier brick. The only thing left was to find one that fits in the narrow space. I found one: the Sony XM-604EQX has one sloping side with cooling fins. It's an almost perfect fit. Only when someone is sitting in the middle of the back seat, which hardly ever happens, the seat touches the cooling fins. Now, you may ask: doesn't that small space restrict air flow and won't the amp overheat because of this? I've thought of this. There's 2 things why the amp won't overheat. First: the amp is pressed against the bottom of the car, and air flows continuously along the steel bottom plate. Second: the amp has a small fan, so should it ever run hot, there's some air flow available.
There's a lot more to the Sony than just the amplifier. Features:
- 4 channels of 60W continuous, 2 by 2 bridgeable into 150 W
- regulated power supply, so no need for a capacitor
- built-in variable crossovers
- a 5-band equalizer with bypass per channel pair
- a power meter per side
I set it up for front left and right, and the 2 back channels are bridged into a single 150W channel, driving the 12" subwoofer. The subwoofer is a Monacor SPH-300TC with its 2 coils paralleled to give a 4 ohms total impedance. The driver sits in a closed 25 liter reinforced plywood enclosure. The box is finished in black carpet, the speaker is grilled and the corners are protected by black steel corners. I had to make a sorta slanted side to the box to make the best use of the space it sits in (in the trunk against the LPG tank, speaker firing forward "into" the LPG tank).
Between the front seats is an arm rest for the driver. The arm rest doubles as a glovebox. In it are my trustworthy Archos Jukebox Recorder 20 and a homebuilt power supply, which supplies 10.4 volts for the Archos and 5 volts for my cellphone and iPAQ. In the console near the handbrake handle I built the source select switch (to select MP3 or radio), the on/off switch for the amplifier, the on/off switch for the charger, and the main volume dial. Next to the armrest is a pilot light for the amplifier, made out of 4 quadruple green leds. That's 80x5 mm of green light reminding me to turn of the amplifier when I get out of the car.
I'm not a cable guy. I see lots of people using fist-thick cables to wire their power, signals and speakers. My positive supply wire is 5 mm2, and I have yet to notice any loss at the amplifier end. Signal wires are the cheapest I could find (the type you buy at Walmart), and speaker wires are 1.5 mm2 lamp cord.
Unfortunately the car suffered extensive engine damage due to a broken timing belt in December 2006. The belt broke just before its scheduled change, resulting in 8 bent valves. A complete cylinder head revision with parts and labour would have cost almost as much as the car's worth. I was offered an OK deal and the car was sold as scrap (but not before I stripped it clean of course).