Electrical/Audio Bullshit

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Yes; it won't break or wear out in the near future.

Why not just try a new head unit? I've seen people sell decent ones for $40-$70.
 
caboose said:
the radio is most likely 180/200/or 208 watts. Probably 208 if it's nice.
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Uh, how's 200 watts even possible? Remember that energy cannot be created nor destroyed, now let's move on:

10 Ampres (The radio and clock fuse rating in a civic.) @ 14 Volts (the average voltage of the car's electrical system with the alternator running properly) gives you 140 Watts of available power.

Out of the 140 Watts, you have the lights on the front of the stereo and the cd player motor, and the car's clock. Let's call this 0.5A, so that's 7 watts.

140 - 7 = 133 Watts left.

Now let's give your stereo the benefit of the doubt, and call it a Class B audio amp (Not the most efficent, but not the best sounding either, good compromise.) That'll have a theoretical maximum of 78.5% efficency.

133 * 0.785 = 104.405 Watts of Audio Energy.

That gives your cd player the maximum output of all channels as about 104 Watts. Divide that by the number of channels (4 in most cases) and that gives you 26 watts.

104.405 watts total output / 4 channels = 26.10125 Watts per channel RMS

So, as you see, 200 watts isn't possible from a head unit, much less, over 26.10125 (significant digit rounding makes it 26.1 W) watts.


Have a great day.


EDIT: I just realized that it'll probably be a Class D ampliflier in the head unit, so replace the 78.5 figure with 95. I also forgot the power lost in heating up the wiring too, so remember to figure that in. It's a rough estimate, but I'd leave the final figure at somewhere around 20 watts per channel maxumim. Remember that in reality, those head units never draw anywhere near the full 10 amps available.
 
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Aleaf.CRX said:
Just replace the belt? Any special tips for that?
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If its not worn out, dont replace it. If all it does is squeak you can put some belt dressing on it and the squeak will stop. Or if you dont wanna spend a couple bucks for a tube of belt dressing, just rub candle wax on the belt, it works every time.
 
awptickes said:
Uh, how's 200 watts even possible? Remember that energy cannot be created nor destroyed, now let's move on:

10 Ampres (The radio and clock fuse rating in a civic.) @ 14 Volts (the average voltage of the car's electrical system with the alternator running properly) gives you 140 Watts of available power.

Out of the 140 Watts, you have the lights on the front of the stereo and the cd player motor, and the car's clock. Let's call this 0.5A, so that's 7 watts.

140 - 7 = 133 Watts left.

Now let's give your stereo the benefit of the doubt, and call it a Class B audio amp (Not the most efficent, but not the best sounding either, good compromise.) That'll have a theoretical maximum of 78.5% efficency.

133 * 0.785 = 104.405 Watts of Audio Energy.

That gives your cd player the maximum output of all channels as about 104 Watts. Divide that by the number of channels (4 in most cases) and that gives you 26 watts.

104.405 watts total output / 4 channels = 26.10125 Watts per channel RMS

So, as you see, 200 watts isn't possible from a head unit, much less, over 26.10125 (significant digit rounding makes it 26.1 W) watts.


Have a great day.


EDIT: I just realized that it'll probably be a Class D ampliflier in the head unit, so replace the 78.5 figure with 95. I also forgot the power lost in heating up the wiring too, so remember to figure that in. It's a rough estimate, but I'd leave the final figure at somewhere around 20 watts per channel maxumim. Remember that in reality, those head units never draw anywhere near the full 10 amps available.
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Radios are measured in peak per channel

52 watts peak X 4 channels= 208watt

EDIT: I also think that most aftermarket radios use a 20A fuse
 
HM. Well, my belt does squeak. I don't know how to tell how worn it is. I'm pretty damn sure that's the stock belt, just like everything else on the fucking car was when I got it (ehem timing belt, headgasket....). I might just replace it, just for the sake of it.
 
Aleaf.CRX said:
HM. Well, my belt does squeak. I don't know how to tell how worn it is. I'm pretty damn sure that's the stock belt, just like everything else on the fucking car was when I got it (ehem timing belt, headgasket....). I might just replace it, just for the sake of it.
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I doubt that it's stock, but you might as well replace it
 
If you have a repair manual they usually have pics in em of belts that need replaced, thatd be a good place to start. Otherwise, look for things like cracks, torn edges, or fraying edges. If non of that is goin on, just rub it down with some wax and youll be good to go.
 
newb said:
If you have a repair manual they usually have pics in em of belts that need replaced, thatd be a good place to start. Otherwise, look for things like cracks, torn edges, or fraying edges. If non of that is goin on, just rub it down with some wax and youll be good to go.
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Although the belt can start to crack, that's not the only thing that can go wrong. What typically happens is that the "v"s or groove in the belt wear out and that's what causes the belt to start to squeak. And I've never heard of "waxing" a belt before.

Unless the belt is loose, just replace it, it's only like $8-12 bucks.
 
caboose said:
Although the belt can start to crack, that's not the only thing that can go wrong. What typically happens is that the "v"s or groove in the belt wear out and that's what causes the belt to start to squeak. And I've never heard of "waxing" a belt before.

Unless the belt is loose, just replace it, it's only like $8-12 bucks.
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When the V's start to wear out they fray, get shiny, crack, or any combination of the 3. And I dunno what to tell you bout waxing a belt. If you didnt know, when belt dressing dries it leaves a wax film on the belt. You can get that same film from a candle purchased at Goodwill for a fraction of the price.
 
You can also use bar soap, or so I've been told.

Yeah, I just checked and it actually doesn't look all that bad.
 
Well, it doesn't squeak constantly. Only every so often. Fuck if I know why though. Anyway, since it doesn't look so bad, I wonder what could be causing the weird electrical things. I haven't checked yet, but I'm pretty sure my voltage is probably off too.
 
Your alternator should put out a constant flow of 13.7-14.7 volts before the voltage regulator.

Personally Id start with grounds, thats what the problems sound like to me, having experienced similar thigns myself (and fixed them myself as well). But, if thats not the problem, and the alternator passes, Id go on to the voltage regulator. If none of that is the problem, you might check for worn wires. I just look for wires that visually dont look good, or wires that feel hot. When your feeling the wires its very easy to tell rather the wire is absorbing ambient heat or generating its own. Wires creating heat deffinitly need replaced quickly.

The easiest thing to do is go to Auto Zone or Schucks and have em run their free charging system check. Thatll at least give you a good starting point.

Also, improper power levels will make electronics do weird things some times. This may be all thats goin on with your CD player.
 
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Yeah, that's what I thought. Well, I have one day off this week, guess I'll be checking wires and voltage levels.....any more ideas, just in case?
 
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