Matching head unit to Alpine MRP-M500 using Fluke DVM

[beech2000]

Okay so decided to use my Alpine MRP-M500 in the boat and I need some help setting it up.

I understand with my head unit at 75% volume my 12" sub wired at 2 ohms. I understand I should have around 31.62 VAC when checked with speaker disconnected and continuous 50htz tone.

500 watts RMS X 2ohms = 1000 The square root of 1000 is 31.62227 so around 31.5 VAC right?

I am only getting 5 or so volts a/c but I have to turn the gain and bass boost all the way up just to get 5 VAC but I am getting sound out of the sub but not great. This is the same problem i have been having with this amp in the truck as well. I tried using another meter (Analog simpson and harbor freight special and same results.) What am I doing wrong????

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[moneypit]

Make sure your sub level is all the way up

Eta: i should have asked if yoir H.U has a sub fade level first. And if it does then make sure its all the way up. Test your meter by checking house voltage. Just stick it in the plug on ac and see if you get 110-120 volts. But i bet its your fade. I ran into the same problem and actully have it happening again on my front amp. Was gonna check to see if the loudness had to be on high like the subs needed the fade on high

 

[jrdnhsnbrg 10+ year member]

make sure headunit EQ is flat, check your RCAs make sure they aren't pinched or broken. Do NOT use the bass boost. Make sure power and ground connections are tight.

 

[beech2000]

Make sure your sub level is all the way up
Eta: i should have asked if yoir H.U has a sub fade level first. And if it does then make sure its all the way up. Test your meter by checking house voltage. Just stick it in the plug on ac and see if you get 110-120 volts. But i bet its your fade. I ran into the same problem and actully have it happening again on my front amp. Was gonna check to see if the loudness had to be on high like the subs needed the fade on high

Okay great I'll do that and recheck. I know my meter is fine as I used two others and same results. Thanks

 

[beech2000]

make sure headunit EQ is flat, check your RCAs make sure they aren't pinched or broken. Do NOT use the bass boost. Make sure power and ground connections are tight.

With bass boost all the way down I am only getting 2 VAC. something is wrong with this Alpine. I also tried using different RCA cable and same thing. I might be sending this amp in for repair.

 

[jrdnhsnbrg 10+ year member]

With bass boost all the way down I am only getting 2 VAC. something is wrong with this Alpine. I also tried using different RCA cable and same thing. I might be sending this amp in for repair.

Grounds and electrical connections are secure? Fuses on the amp are making clean connections?