Setting Gain

[jonerickson1]

I have a

mrp-m1000 alpine amp, 1000w rms @ 2ohms.

Fosgate T1D410 4 ohm DVC wired @ 2 ohms 600w rms

I tried the 40 hz 0 db test tone and used the DMM to set it to 35 volts

It sounds ok but doesnt seem to be pushing the sub too hard.

when i play a regular song it only reads about 20 volts

I know the music signal isnt a sine wave but is that voltage still a representation of the power going to the sub?

How hard can i push it?

How do you do the distortion method?

Is that a good method?

Any other tips/ tricks would be nice. This is my first install.

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[TheFiverMan 10+ year member]

get you a -3db 40hz test tone. see if that helps

 

[rumple4skin 10+ year member]

I have amrp-m1000 alpine amp, 1000w rms @ 2ohms.

Fosgate T1D410 4 ohm DVC wired @ 2 ohms 600w rms

I tried the 40 hz 0 db test tone and used the DMM to set it to 35 volts

It sounds ok but doesnt seem to be pushing the sub too hard.

when i play a regular song it only reads about 20 volts

I know the music signal isnt a sine wave but is that voltage still a representation of the power going to the sub?

How hard can i push it?

How do you do the distortion method?

Is that a good method?

Any other tips/ tricks would be nice. This is my first install.

ideally you want to be hitting that 35v each bass note but you need to insure that you have proper charging to the bat in your system to make sure you do not drop low voltage. i also suggest you install a volt meter in your car

 

[helotaxi 5,000+ posts]

You do not want to hit 35v with every bass note because you would have effectively compressed the music and it would actually sound flat. If you want more output, use a -3dB test tone as previously recommended or set it by ear on music. I would only recommend the latter if you know what you're listening for in the way of distortion from the sub. Realize that it is not very easy to hear most of the time.

 

[jonerickson1]

You do not want to hit 35v with every bass note because you would have effectively compressed the music and it would actually sound flat. If you want more output, use a -3dB test tone as previously recommended or set it by ear on music. I would only recommend the latter if you know what you're listening for in the way of distortion from the sub. Realize that it is not very easy to hear most of the time.

What is the difference between the -3db test tone and the 0db test tone? Is 40 Hz the correct testing frequency?

This is my first time on this site and I am surprised at all the help. Thanks everyone for the help

 

[jonerickson1]

I am experiencing some light dimming. Is this better solved by another battery or the BIG 3?

Battery suggestions?

 

[benzmansl65amg 10+ year member]

big 3 is cheaper if you get a batt do both big three is only 25 dollars batt will help. How many watts rms?

 

[jonerickson1]

big 3 is cheaper if you get a batt do both big three is only 25 dollars batt will help. How many watts rms?

The sub is a fosgate t1d410 600 rms. In my car the battery is mounted in the trunk stock so running a bigger 1/0 cable would be pretty exspensive.

 

[Wildbillpb 10+ year member]

Sure you wired the sub right? Also big three would still be cheaper 20 ft of 0/1 gauge is cheaper than another battery and for 1k watts that should be all you need.. It also helps in the long run incase of any upgrades

 

[Wildbillpb 10+ year member]

I don't know if this is right but being -3 db makes you turn up the gain a bit more as it will be a lower output in watts

 

[kr15 5,000+ posts]

congrats to a new member trying to get something done the right way

 

[helotaxi 5,000+ posts]

What is the difference between the -3db test tone and the 0db test tone? Is 40 Hz the correct testing frequency?This is my first time on this site and I am surprised at all the help. Thanks everyone for the help

A 0dB tone give maximum output from your head unit because it is the highest level source signal. The benefit of using 0dB tones is that no mater what the recording level of the music, it can never exceed that signal level and if your amp is not clipping with a 0dB tone it cannot possibly clip on music.

The drawback of using 0dB tones is that the vastly overwhelming majority of music does not approach 0dB in recording level even on the loudest transients. What that means is that you have amplifier potential that you are not using because the signal from the music is never getting to the level that you used to set the amp. Using a 3dB tone lets you get some of that back and since most music doesn't get to -3dB either you still usually have a margin of safety.

To determine whether or not 40hz is the right freq we have to know where your crossover is set. As long as the crossover is set a good bit higher while you're setting the gain and you don't have a subsonic filter engaged, 40hz is just fine.

As far as the dimming, the power rating of your sub has no bearing on that, only the actual power output of your amp and its efficiency. As already suggested, the Big 3 is your first step. If you're still having problems after that, make sure that your battery is good. If it is, you might start considering adding a second battery. With a 1kW Class D amp that shouldn't be needed.

 

[jonerickson1]

SO what i gather from this is to go with the big 3 instead of a battery. I also purchased a voltmeter to see how much my voltage is dropping. Whats the best deal on 1/0 wire? I have seen that some places have more shielding and barely any wire. I definately dont want 4 gauge that says its 1/0. lol

 

[Wingsfreak9 10+ year member]

just crank the gain all the way to the right and see what happens. should get movin a lil bit

 

[jonerickson1]

just crank the gain all the way to the right and see what happens. should get movin a lil bit

lol. i dont think i will give that a shot