i have a question....

[89tben 10+ year member]

ok guys first of let me start by saying im a newb. not a newb to car audio, but a newb to doing car audio right. IE setting gains, building the box for the speaker etc. so go ahead and flame me if you will, i dont mind jokes. but i am here to learn how to do things the right way.

ok heres what i have. a clarion vrx745vd, cheap ligthning audio 4 inchers in front and stock speakers in the back. i also have 2 old skool fockford fosgate punch 500.2 2 channel amps. only one is installed in my car at the moment, and its powering 2 kicker cvr's with 4ohm dvc's in a crappy single chamber small prefab sealed box. the subs are wired to run at a 4ohm load off the amp. the amp is bridge to 1 channel. you can check my gallery if youd like to see my amps and the sub that i will be installing later on. the big amps are rated at 1000 w rms. so after doing alot of reading on here i figured id go and try to set my gains with my dmm. set the dmm to ac on the 200v mode. i dont have a test cd but i do have a bass cd with a 50Hz tone. pop the cd in, turn on the amp cancel on the hu, and check the voltage. it bounced around a bit. i messed with the gains. bounced around some more. came back and checked the chart to see where the voltage should be and it didnt look right. so i go back out and turned the gains and the bass boost all the way up. max voltage on the amp i got was 47 volts give or take.

according to the chart thats only 550 wats or soo. not right. changed amps out and got lower readings off that on( tho i was in a hurry to change them out and everything might not have been tightened completely). and i know i shoulnt have been in a hurry. second amp topped out at 31 volts. 250 watts. not fight either. both amps produce great sound. @ 50Hz they knock pretty good.

so does anyone have any ideas? is there something i did wrong? is there any more info i need to provide?

oh and a few other things

1 these amps have the cross over card in them. they are set at low pass 80Hz i believe.

and i checked for voltage loss at the amp. very very minimal. like 14.29v at the alt and 14.25v @ the amp. please help.

thanks in advance.

ben

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[89tben 10+ year member]

bump

 

[gunz4me 10+ year member]

Were your subwoofers connected? If so, it is possible that impedance rise came back to kill your power output, although it shouldn't be that much.

Do you know which dB level your test tone was recorded at?

What is the quality of your DMM?

Lastly, please keep in mind that although the DMM gain setting method is nice, it does have drawbacks.

I would recommend that you download your test tones from *here* and use *Audacity* to make a 50 or 60 Hz test tone about 20 minutes long before burning it to CD.

Of course, you should trust your ears over the DMM gain method while at the same time realizing that the DMM gain setting method is highly inaccurate if you don't have an oscilloscope to determine clipping!

 

[89tben 10+ year member]

Were your subwoofers connected? If so, it is possible that impedance rise came back to kill your power output, although it shouldn't be that much.
Do you know which dB level your test tone was recorded at?

What is the quality of your DMM?

Lastly, please keep in mind that although the DMM gain setting method is nice, it does have drawbacks.

I would recommend that you download your test tones from *here* and use *Audacity* to make a 50 or 60 Hz test tone about 20 minutes long before burning it to CD.

Of course, you should trust your ears over the DMM gain method while at the same time realizing that the DMM gain setting method is highly inaccurate if you don't have an oscilloscope to determine clipping!

ok lets see here. no the speakers were't connected.

i have no idea what the test tone was recorded at. its just a 50Hz tone on a bass cd that i have.

the dmm is probably not the best quality but i just bought it yesterdat at walmart. its an Etek 10709.

yea i know that the dmm method isnt the best but i figured id give it a shot. the reason i did is because i had my gains and the bass eq on my amp turned almosy all the way up. and i dont think thos kicker cvrs should be able to handle the power that amp produces. granted when i did crank my stereo it wasnt cranked for very long as i dont drive my car that much. id say 30 mins at most usually. i was another post and some described clipping as "the sound doesnt get louder, just muddier". i think ive experienced this befor when i turn it way up. but i dont ever usually listen to it at that level.

another thing i thought of last nite is these amps hve the crossover card in them, and there are set up as lowpass right now. i didn't change them. would that change the results of the dmm test?

and another thing about these amps is they dont have a bridging switch. they automatically switch between 2ch and bridged.

like i said, im a newb to this, setting gains and etc. and i just dont want to damage my amps. i love these things. the kickers im not too worried about. of course im not just gonna try and blow them either.

also i dont have a scope right now, and i dont know anyone that does.