Is this the right way to set up an amp?

[mac208x 10+ year member]

I came across these steps, and i was wondering if this is actually correct on how your suppose to set up the gain etc on the amp so it doesnt clip etc....

1.) Calculate the target output voltage. It's a pretty simple equation.Output Voltage = the square root of RMS wattage X the Final ohm load.

Example: 1000 W RMS X 2 Ohms = 2000

And, the square root of 2000 is 44.72. In this example, 44.72 is the target output voltage.

2.) Set all of the controls for the bass, on the head unit and the amp, to zero. ( gain, boost, bass control)

3.) Disconnect the subs

4.) Turn off, or disconnect the mid and high range speakers in the car.

5.) With the engine running, pop in the 50hz test tone, on repeat, and crank the volume to about 3/4 of the head unit's capacity. If it goes to 40, turn it to 30. This is usually the point just before the signal will start to degrade.

6.) Set the Multimeter to AC voltage. Then see what you get for an output.

7.) Slowly turn up the gain, boost, and bass, until you reach your target voltage. On most amps, this is the point just before the amp starts to clip. Clipping causes distortion. Which will cause a ton of problems. Including the one that you have now.

8.) Turn down the volume and eject the test tone CD from the head unit.

9.) Turn everything off.

10.) Reconnect everything.

Click to read more...

 

[mast240 10+ year member]

yup... spot on

except, when setting with a dmm... i would just leave the bass boost off.

 

[IonRL205 10+ year member]

Does having the HPF on your deck affect the voltage in any way? I wouldn't think it would, but as much as I like hearing a 50 hz test tone blast through my door speakers, I'd rather have the HPF on //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Wasn't sure if it affected the signal in anyway.

 

[mast240 10+ year member]

your hpf wont, as long as your running the subs off a sub pre out... and even then, it really wont affect anything...

your voltage is only going to be affected by either the tone being played (50 hz test note, the hpf wont affect it, unless you have your x-over tuned really weird), or the impendance

 

[mac208x 10+ year member]

Yeah thats what i was gonna do, what about the ss, phase and low pass?

yup... spot on
except, when setting with a dmm... i would just leave the bass boost off.

 

[IonRL205 10+ year member]

Subsonic (SS) is used to block out frequencies below what you set it at. So if it's at 25 hz, you wont play anything lower than 25 hz.

Phase you should just leave at 0, it's meant if your subs are playing out of phase, you can fix it so they are playing together.

Low pass only plays the frequencies up to the point you set it at, and blocks out anything above it. So if it's at 80 hz, you won't play anything higher than 80 hz

I normally put my SS at 25 hz and the LPF at 80 hz. The phase you shouldn't have to touch.

 

[mast240 10+ year member]

depends on your box set up...

subsonic will be the bottom end, lpf is the top end... think of it that way...

and phase should be set to 0... unless you have an isobarak, or inverted subs

 

[mac208x 10+ year member]

Cool thx ;p

Subsonic (SS) is used to block out frequencies below what you set it at. So if it's at 25 hz, you wont play anything lower than 25 hz. Phase you should just leave at 0, it's meant if your subs are playing out of phase, you can fix it so they are playing together.

Low pass only plays the frequencies up to the point you set it at, and blocks out anything above it. So if it's at 80 hz, you won't play anything higher than 80 hz

I normally put my SS at 25 hz and the LPF at 80 hz. The phase you shouldn't have to touch.

 

[IonRL205 10+ year member]

low pass, should be tuned to what your box is tuned to

My box is tuned to 31 hz and there's no way I'm gonna block out everything above 31 hz. 60 to 80 hz is a good place to put it, not your box tuning frequency. Don't you mean the SSF should be tuned to where your box is tuned to?

 

[mac208x 10+ year member]

wait actually i got another question, kinda dumb but i wanna make sure, u put the dmm up to the speaker terminals right? lol

 

[IonRL205 10+ year member]

Yes, you put them in the speaker terminals.