Re: wire size FYI
How much voltage drop is acceptable depends on the design of your equipment and the performance you want from it. Maybe you can tolerate distortion due to your amps going non-linear during peaks. Or if your amps have regulated power supplies, they might hold their output even when the input drops (within limits). But some amps will become unstable and oscillate if the power line impedance is too high. Most amps' output power is directly proportional to the input voltage. Maybe you don't care if you lose some. Most people do.
Originally posted by Steven
People have told me that if you use too small of wire then the resistance of the wire will cause a "severe" voltage drop. but what is a "severe" voltage drop. I've had people say that more than 2 volts is unacceptable while others say that more than 0.5 volts is reason enough to go up one size in wire. Well if voltage drop is so bad, then what happens when that big bass note comes along - the voltage in my car (with engine running) sometimes drops below 8 volts (measured both at the battery and at the amps). Thats over a 6volt drop - better increase my wire size to 000. B.S.
Wire gage has 2 aspects: safety and voltage drop. Safety is the wire heating up beyond 40 degrees above ambient (NEC codes). That is affected only by wire gage and the ~average~ current. The wire gages recommended for car audio are way overkill if you're looking at safety only.
But music has about a 5:1 peak-to-average ratio, and those peaks are important if you want a system that thumps and remains clean at high levels. That's where voltage drop becomes important.
BTW if your battery voltage is going to 8 volts, your alternator isn't long for this world.
1999 Buick Park Ave Ultra
Head Unit: JVC KWHDR720
EQ: Audiocontrol EQL
Front Stage: Hybrid Audio Technologies Imagine 5.25 mids, Morel Maximo tweets
Sub Stage: Boston G3 10", 0.5 cu ft sealed
Amp: PPI Phantom 900.4
Rear Fill: Boston SE953 6X9's