Voltage Drops With Good Electrical And Low Wattage?

[Kasey]

if you have your subs wired to 1 ohm you are going to produce 3000 watts of power in a perfect condition.

when you set the gain you are, like you said, matching the head unit output voltage to the amplifier input voltage.

you are not telling the amplifier how many watts it should produce.

the only way to change the wattage is to change the ohms... the resistance.

2 ohms is more resistance than 1 therefore it will produce less wattage at optimum voltage (hence correct gain setting).

but like David already said that amp won't even produce 1600 watts at 2 ohms.

hope this helps.

cud not have seed it better my self

[Boon]

P = V^2/I

P = 56.57^2/1

56.57vac @ 1 ohm = 3200w ;/

EDIT: And you can control the power output of the amp using the gain. If you set the gain using a 0dB tone at maximum headunit voltage then the amp will never see higher INPUT voltage than that so you will never see higher output voltage than what you set it for....

Edited March 20, 2009 by Boon

[95_1500]

I see what you're saying.. I read my meter wrong, 36.2.. i thought that was a bit high at 1 ohm so i rechecked it. so im actually putting out about 1300 watts. Shit just got real lol. Well i appreciate the feedback guys.

[Derrick824]

Can you explain? Then why do you set the gain?(i understand to match the hu output and amp input) I just checked, its a pretty hot day truck has been in the sun all day, 12.57 at the d3100 and 12.54 at each of the front batts. Cannot find a loose connection. I am at the dorm, might go home to charge it in the garage tonight and do laundry, there i will be able to do much better troubleshooting.

It's hard to pinpoint an electrical issue such as this without a lot of testing adn checking. I can tell you that if your d3100 is only resting @ 12.5v then that's a problem. It should rest around 13v if properly charged. I'm leaning towards this possibly being a faulty alternator causing improper charging resulting in your batteries draining quickly.

[soundzright]

intresting, anyone else have an issue with iraggi alts an xs batteries? Steve my know also as he runs these alts and batteries doesnt he?

[thehoe92]

try checking the belt.

it could be loose and not getting the right grip and powering your batts right.

[mike fallon]

Ok I might not know a lot but here are some ideas for ya.

1. Gain controls only allow you to use a different voltage input on the amp, not control the volume. You will never get 5 volts out of the radio. If you want to check the output of the radio then you need to measure the input resistance of the amplifier and make a resistor pack that matches it and set the gain at the max voltage of the radio under load.

2. The voltage output at the amp doesn't mean anything unless you know the amperage at the same moment or the actual resistance of the system at that frequency and power level.

3. The voltage drop you are seeing may be normal for your system. Check the front battery drop and rear battery drop at the same time. If the front and back drop the same amount then the electrical system is being taxed that much under normal conditions. If the back battery drops more then you need to run more charging and return wires. Remember that the alt actually charges the Negative wire and returns the positive.

4. Check the grounds in the system for voltage differences. See if the voltage at the ground point is the same as at the end of wire.

5. Check for voltage difference in the resting voltage of the car. If there are differences then rewire.

6. Try and swap the d3100 to the front of the car and see if the voltage comes up.

[creyc]

That sounds like an alternator issue to me. But then you didn't mention if you upgraded your alternator charging wire, or the rest of the big 3? Check that first.

I'm running a SAZ-3000D at the full 3kW off a 250A mechman alt, yellow top and kinetik 1800. On songs with long bass sections, like Prime Minister, Airforces, etc, I drop to mid 13v but never lower.

So with you pulling even less power from the amp, your alternator alone should be able to feed it enough power I would think. If that was my setup I'd temporarily take out a few of those batteries and see if the problem is identical. I don't think the batteries alone could be pulling enough current (while charging) to cause this kind of an issue but may as well check..

[David]

Ok I might not know a lot but here are some ideas for ya.

1. Gain controls only allow you to use a different voltage input on the amp, not control the volume. You will never get 5 volts out of the radio. If you want to check the output of the radio then you need to measure the input resistance of the amplifier and make a resistor pack that matches it and set the gain at the max voltage of the radio under load.

2. The voltage output at the amp doesn't mean anything unless you know the amperage at the same moment or the actual resistance of the system at that frequency and power level.

3. The voltage drop you are seeing may be normal for your system. Check the front battery drop and rear battery drop at the same time. If the front and back drop the same amount then the electrical system is being taxed that much under normal conditions. If the back battery drops more then you need to run more charging and return wires. Remember that the alt actually charges the Negative wire and returns the positive.

4. Check the grounds in the system for voltage differences. See if the voltage at the ground point is the same as at the end of wire.

5. Check for voltage difference in the resting voltage of the car. If there are differences then rewire.

6. Try and swap the d3100 to the front of the car and see if the voltage comes up.

quoted for truth.

the gain is not a volume knob EVER.

[95_1500]

I appreciate all the info guys. So those charts with like wattage at certain ohms to achieve cetrain watts is meant to look at and set the voltage to whatever your amp is. Like mine should be set to 54.77 for 3000 watts at 1 ohm? Looks like i need to hurry up and get my lv 5s. I ordered some more knukonceptz ultra fleks wire, going to have 2 runs from front to back and 2 grounds and see if that helps keep me above 12. The lowest i saw today was 11.8. Also have the truck on trickle charge tonight so when i go back to the dorm tomorrow theyll be nice and charged.