Well, as you can see by the title, I'm experiencing some significant voltage drop at my amp. It's an SAZ-1000d and my alternator is a 240a Iraggi. I have just one battery under the hood. It was sitting idle at about 13.3 at the battery and amp. Full tilt on music, it stays at 13.3 at the battery, maybe dropping .1v, but at the amp, it can drop down into the 11.5 range.

The wiring for the amp is probably too small, it's a 4 gauge wiring kit I got pretty cheap on sonicelectronix.com, so I'm guessing that is probably my problem. The amp says it uses 4awg, but the 4awg I have might be on the small side, I'm not sure. What do you think?

Well, as you can see by the title, I'm experiencing some significant voltage drop at my amp. It's an SAZ-1000d and my alternator is a 240a Iraggi. I have just one battery under the hood. It was sitting idle at about 13.3 at the battery and amp. Full tilt on music, it stays at 13.3 at the battery, maybe dropping .1v, but at the amp, it can drop down into the 11.5 range.

The wiring for the amp is probably too small, it's a 4 gauge wiring kit I got pretty cheap on sonicelectronix.com, so I'm guessing that is probably my problem. The amp says it uses 4awg, but the 4awg I have might be on the small side, I'm not sure. What do you think?

Maybe you should try some better wire. Checking your grounds, fuses. See if your subs are wired right.

Well, as you can see by the title, I'm experiencing some significant voltage drop at my amp. It's an SAZ-1000d and my alternator is a 240a Iraggi. I have just one battery under the hood. It was sitting idle at about 13.3 at the battery and amp. Full tilt on music, it stays at 13.3 at the battery, maybe dropping .1v, but at the amp, it can drop down into the 11.5 range.

The wiring for the amp is probably too small, it's a 4 gauge wiring kit I got pretty cheap on sonicelectronix.com, so I'm guessing that is probably my problem. The amp says it uses 4awg, but the 4awg I have might be on the small side, I'm not sure. What do you think?

Maybe you should try some better wire. Checking your grounds, fuses. See if your subs are wired right.

What would I be checking on the grounds and fuses?

Well, as you can see by the title, I'm experiencing some significant voltage drop at my amp. It's an SAZ-1000d and my alternator is a 240a Iraggi. I have just one battery under the hood. It was sitting idle at about 13.3 at the battery and amp. Full tilt on music, it stays at 13.3 at the battery, maybe dropping .1v, but at the amp, it can drop down into the 11.5 range.

The wiring for the amp is probably too small, it's a 4 gauge wiring kit I got pretty cheap on sonicelectronix.com, so I'm guessing that is probably my problem. The amp says it uses 4awg, but the 4awg I have might be on the small side, I'm not sure. What do you think?

Maybe you should try some better wire. Checking your grounds, fuses. See if your subs are wired right.

What would I be checking on the grounds and fuses?

Your amps fuses and make sure it has a nice ground. I always like checking the little things because they lead to big things. So i check everything pretty often

Edited April 8, 201015 yr by cheese20323

your voltage will likely stay the same from the front to the rear when there is no or a low load flowing through that long power wire.

Once a significant load is sent through the wire, you will get to see the full extent of your voltage drop issue when you are not using large enough wire that long, not having a battery in the back.. or having other problems like bad ground.

IT should be typical for you to see a 0.5v drop during a load from the front battery to the amp...

However, because you are seeing a lot more than that, it's not the size-to-length of the wire.... sounds like loose connection somewhere.

"Our Kits include oversized (Kolossus) Power Cable. With 2058 Strands of Tinned Oxygen Free Copper, no other manufacture offers a 4 gauge cable like this." - KnuKonceptz

I recommend them if you want to get better wire. I believe it is 45-50 dollars for a 4 gauge amp kit.

your voltage will likely stay the same from the front to the rear when there is no or a low load flowing through that long power wire.

Once a significant load is sent through the wire, you will get to see the full extent of your voltage drop issue when you are not using large enough wire that long, not having a battery in the back.. or having other problems like bad ground.

IT should be typical for you to see a 0.5v drop during a load from the front battery to the amp...

However, because you are seeing a lot more than that, it's not the size-to-length of the wire.... sounds like loose connection somewhere.

So I don't get what you are saying. You say that if u are not using large enough wire for the amp, you will see voltage drop, but you are saying that's not my problem?

BTW, here's the wire kit I have. I actually bought it to hook up a 600w Hifonics amp years ago, and it worked fine for that.

If I were to replace the wire, I'd probably just get 1/0 and use a reducer adapter. That way I can upgrade easily in the future.

Also, another question sort of relating. I'm pretty sure I'm using the jeep's stock alternator regulator. I'm basing this assumption from the fact that when I installed my alt, I just connected the stock connections to it as well as the big 3. I've noticed when my car is cold, I have pretty good voltage, right around 14, but when the engine starts to warm up or if it's warm at the start, the voltage sits lower, like at 13.4. Is that normal, or should I look at getting an external regulator or something?

that's normal. Voltage will increase with rpms and\or a load present.

that's normal. Voltage will increase with rpms and\or a load present.

Well, assuming the voltage gauge on my dash works right, it doesn't seem like the voltage goes up with higher rpms when the alt is warm. If it's cold, it'll sit comfortably at 14v. I mean, it could be the gauge is affected by heat and shows lower voltage then it really is, so I'll have to test that somehow.

Your voltage will always read higher when it is colder out, temperature is what affects voltage (usually on hotter days your car will start and idle at a lower voltage then moderately or chilly temperature days).

Your voltage will always read higher when it is colder out, temperature is what affects voltage (usually on hotter days your car will start and idle at a lower voltage then moderately or chilly temperature days).

I understand how the idle could affect the voltage, but it seems that my voltage will be lower on warm or hot days no matter the rpm's. It seems strange to me that it would be that drastic of a difference from temperature alone.