Tuning an amp (NOT A, HOW TO?!)

[tsenfw 10+ year member]

You have to get a test tone. Get a .wav sound file of it and burn it to cd. 60hertz at 0db. I'll get you a link in a sec.

EDIT* here's a link: http://www.realmofexcursion.com/jmac/audio/0dB_wav_test_tones/60%20Hz.wav

realm of excursion has tons of tones on their download section.

Disconnect your sub. Put the positive lead of the mulitimeter in the positive output of amp and negative to negative. Put the multimeter on the AC voltage setting. Don't forget volume at 3/4 or the cleanest sounding highest volume you woud listen too. Turn off the other speakers if your headunit allows it.

Tell me what watts and what ohm you need, I'll put them in the equation as an example. I used excel it was pretty easy.

Mike - not sure if that equation is fool proof, but it's probably a really close ballpark for setting the gain on your amp.

 

[miker 5,000+ posts]

Not sure of the watts... lol.

SHOULD be 1000 for sub, and 1300 for amp. @2 ohms. (will be my new setup not sure when I can buy new subs though...)

OR 600 for sub, 900 for amp. @4 ohms (current setup.. Hope I get rid of it soon, but I still don't want to ruin my amp)

And lastly, 200 total for amp @4 ohms. (speakers)

If all my speakers are turned off, how do I know what volume it starts distorting at? Also if my amp isn't tuned correctly it will distort at different levels? Right? Or should I just turn it up 3/4 and not worry about all that. Also I am going to do -3db. Sounds like I will get the most out of that level.

 

[tsenfw 10+ year member]

hmm don't know what you are talking about with different wattage for sub and amp.

You want to closely as you can match the amp wattage output to the rms wattage rating of the sub. So if you want to run your sub at 1000watts @ 2 ohms you should set your amp to 1000watts @ 2 ohms (using voltage number derived from the formula)

Sqrt(1000watts * 2 ohms) = 44.72volts

As for free balling it. Just turn up the gain until you hear distortion or it sounds crappy then back off quite a bit till it sounds good. You can still ruin a sub at 3/4 gain.