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That's how you burn stuff up....

The only time you should use a DVOM is if you are gain matching multiple amps on multiple speakers.

i may have missed something, but i would think playing tones and setting with a dmm would be more conservative if anything. how would that burn stuff up?

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That's how you burn stuff up....

The only time you should use a DVOM is if you are gain matching multiple amps on multiple speakers.

i may have missed something, but i would think playing tones and setting with a dmm would be more conservative if anything. how would that burn stuff up?

If you think about the funky equation it is telling you that in order to get say 1000 watts at 2.5ohm, you need to have 50 volts, and 20 amps.

To get the amp to put out the 50 volts that you are looking for with your dvom you have to crank your gain all the way and max out the head unit, even then you are still only at say for example 42 volts. Resulting in a 100% square wave, once the woofer load is put on the amp. JL should be shot for coming up with a method like that...making things waaaaaaay too complex.

Rule of thumb, 3/4 or less, 1/2 on the gain if not less is best. Moral of the story the only point of having a gain is to match the input signal that your RCA's are giving the amp....nothing more, nothing less. If you abuse it your woofers will tell you (the smell).

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That's how you burn stuff up....

The only time you should use a DVOM is if you are gain matching multiple amps on multiple speakers.

i may have missed something, but i would think playing tones and setting with a dmm would be more conservative if anything. how would that burn stuff up?

If you think about the funky equation it is telling you that in order to get say 1000 watts at 2.5ohm, you need to have 50 volts, and 20 amps.

To get the amp to put out the 50 volts that you are looking for with your dvom you have to crank your gain all the way and max out the head unit, even then you are still only at say for example 42 volts. Resulting in a 100% square wave, once the woofer load is put on the amp. JL should be shot for coming up with a method like that...making things waaaaaaay too complex.

Rule of thumb, 3/4 or less, 1/2 on the gain if not less is best. Moral of the story the only point of having a gain is to match the input signal that your RCA's are giving the amp....nothing more, nothing less. If you abuse it your woofers will tell you (the smell).

true dat, never thought about it that way....ive been a lemming :) although ive done it the exact same way in the past, before i started to set my gains by ear and got my EQ with a clipping led, and it worked perfectly fine, nothing blew up on me... if anything i needed to bump the gains even more to get the results i wanted.

edit: he also didnt say wat his input voltage was...like the higher the input voltage, the lower you need to turn your gains up. of course that will be taken into consideration once he puts his dmm in the speaker terminals no?

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That's how you burn stuff up....

The only time you should use a DVOM is if you are gain matching multiple amps on multiple speakers.

i may have missed something, but i would think playing tones and setting with a dmm would be more conservative if anything. how would that burn stuff up?

If you think about the funky equation it is telling you that in order to get say 1000 watts at 2.5ohm, you need to have 50 volts, and 20 amps.

To get the amp to put out the 50 volts that you are looking for with your dvom you have to crank your gain all the way and max out the head unit, even then you are still only at say for example 42 volts. Resulting in a 100% square wave, once the woofer load is put on the amp. JL should be shot for coming up with a method like that...making things waaaaaaay too complex.

Rule of thumb, 3/4 or less, 1/2 on the gain if not less is best. Moral of the story the only point of having a gain is to match the input signal that your RCA's are giving the amp....nothing more, nothing less. If you abuse it your woofers will tell you (the smell).

hey nick if i have access to an oscope but its not in a location where it can be moved or come close to the car would i be able to adjust the amps gain withought it being hooked up to the hu or would that defeate the purpose? Im thinking it would need to be hooked up but i could be wrong

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hey nick if i have access to an oscope but its not in a location where it can be moved or come close to the car would i be able to adjust the amps gain withought it being hooked up to the hu or would that defeate the purpose? Im thinking it would need to be hooked up but i could be wrong

it has to be hooked up to your head unit/line driver/LOC watever with some RCA's to set your gains correctly

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That's how you burn stuff up....

The only time you should use a DVOM is if you are gain matching multiple amps on multiple speakers.

i may have missed something, but i would think playing tones and setting with a dmm would be more conservative if anything. how would that burn stuff up?

If you think about the funky equation it is telling you that in order to get say 1000 watts at 2.5ohm, you need to have 50 volts, and 20 amps.

To get the amp to put out the 50 volts that you are looking for with your dvom you have to crank your gain all the way and max out the head unit, even then you are still only at say for example 42 volts. Resulting in a 100% square wave, once the woofer load is put on the amp. JL should be shot for coming up with a method like that...making things waaaaaaay too complex.

Rule of thumb, 3/4 or less, 1/2 on the gain if not less is best. Moral of the story the only point of having a gain is to match the input signal that your RCA's are giving the amp....nothing more, nothing less. If you abuse it your woofers will tell you (the smell).

hey nick if i have access to an oscope but its not in a location where it can be moved or come close to the car would i be able to adjust the amps gain withought it being hooked up to the hu or would that defeate the purpose? Im thinking it would need to be hooked up but i could be wrong

Hook everything up, back your gains down all the way. Turn your volume knob up to where you would listen to it at its loudest point...then adjust the gains up accordingly. General rule of thumb is half way with the gain, no more then 3/4 (which is if you have a low voltage deck). You will be able to hear the distortion once you get to the point where its clipping, go to that point and back the gain off a little bit at that volume setting. You should be fine...

Just takes an ear for it :).

Thanks

-Nick

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cool thats how i did it the first time and i think i got it pretty good but i wanted to see if i could do better with the oscope

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Not sure if there is an appropriate temp... what I would say is that if you smell coils getting hot or burning, that you need to back off. This is a much better indicator of a problem. If I play a sub for 10 hours and the coil is only 200 degrees, everything is fine temp wise for that coil, but the motor and dustcap would probably be very hot too. Now if I played the sub for 15 seconds and the coil was burning and stinking, it is possible that the dustcap would be no where near as hot as it was in the previous example (and Im sure the motor would be just as cold as when it started). But you definitely would have issues with the sub.

Pay attention to the coil and smell more than the dustcap :)

Thanks,

Scott

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Thanks for clearing that up

The cap only gets hot after about an hour but NOT 200 degrees

Ill be posting my new set up in a coupple hours

Thanks so much to all the good people over at FI

I LOVE LOVE LOVE my new baby

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