Voltage and output question

[bassaholic 10+ year member]

Ok i have a Total Mobile Audio Amp which is rated at 500 rms @ 2 ohms and i have a 12Jlw6v2 ok i realise sometimes when i play certain songs the sub appears to be clipping so i pull out my test tone cd and run some test.Anyways i went through different tones individually with my dmm on the speaker terminals to figure out the output of my amp and i realise 2 things, (1) the sub is clipping with only 28 volts out from the amp 500 watts rms should do like 31 volts b4 clipping starts and (2) voltage to the amp reads like 12.50 volts with the car running. What you suggest? is this amp not giving what it say it does or do i need to do something with the electrical?

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[OhioRed 10+ year member]

I would get a multimeter and make sure 14.4v is getting to the amp

 

[squeak9798 5,000+ posts]

My first question is.....how do you know the amplifier is clipping ?

 

[bassaholic 10+ year member]

well its quite audible and when i was checking it it started to give off that smell of death //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif (burny scent).But im leaning towards getting more voltage to the amp.

 

[helotaxi 5,000+ posts]

The amp probably isn't making rated power, or you don't have a true RMS multimeter, or both. By the time clipping is clearly audible, you are well past the onset especially on subs. Without using a clipping detection circuit, which someone on here is working on, you need an o-scope to detect clipping. Without one you are just guessing.

 

[Tirefryr 10+ year member]

a clipping detection circuit, which someone on here is working on

Subscribing for more info.//content.invisioncic.com/y282845/emoticons/naughty.gif.94359f346c0f1259df8038d60b41863e.gif

 

[squeak9798 5,000+ posts]

Subscribing for more info.//content.invisioncic.com/y282845/emoticons/naughty.gif.94359f346c0f1259df8038d60b41863e.gif

http://www.caraudio.com/forum/showthread.php?t=130666

http://www.caraudio.com/forum/showthread.php?t=132031

http://www.caraudio.com/forum/showthread.php?t=145381

 

[Lakota 5,000+ posts]

I got around 70v on a burp with my amp, and approx 14.6v Not sure if it clipped or not though, but it's rated at 850 @ 14.4v (992 on birthsheet iirc).

 

[bassaholic 10+ year member]

Yes my multimeter is a true rms meter and do u think my voltage drop can be causing the problem seeing that my amp is rated @ 14.4 and when i was testing the voltage droped to 12.5 volts?

 

[helotaxi 5,000+ posts]

I'm assuming that the amp is running a loosely regulated power supply. If that is the case then the voltage drop is probably a lot of the problem. I've never heard of Total Mobile Audio. It is quite possible that I doesn't make its rated power at least @ 12V. What does the voltage measure at you battery terminals with the engine on. If it is only 12.5 V there, you have a problem with your alternator or battery. If it is in the 13.5-14.4V range, you have a voltage loss somewhere in your wiring. Check all the connections between the battery and the amp and make sure that you have a good ground. Measure the voltage between your pos battery post and your ground point. If it is much lower than the terminal voltage of the battery, you have a bad ground path. To check the other side of your wiring, check the voltage between the neg battery post and the +12V wire on the amp. Again you should have minimal drop.