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Discussion Starter #1
How to Set your Gains with a Multimeter - YouTube



So I followed this guys steps.

And my amplifier is a us amp ax3000de

It is rated for 2000w @ 2 ohms

So I am supposed to set the gain to 63.25

But it maxes out at 31.5?

What is that all about?
 

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Is your sub control on your HU turned up?

I have to set my HU to +15db for my head unit to send a full signal to the sub amp. You may have a similar thing going on.
 

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Discussion Starter #3
Is your sub control on your HU turned up?

I have to set my HU to +15db for my head unit to send a full signal to the sub amp. You may have a similar thing going on.
OH. my amp probably wasn't getting the HU's full signal.

That makes sense. Because my headunit doesn't distort for the bass until volume 61
but the front speakers distort @ 57-58

so I keep the volume @ 55-56

I will have to play with the subwoofer bass.
 

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That's a good tutorial, but not sure if you are aware of the head unit settings prior to setting up the amp witha digital multi meter. When setting up a amp with a DMM you generally want to set the head units volume at 75% volume so if the head unit max is 62, the volume you have to work with is 46 or if your mid's/high's distort before this 46 volume it'd be a good idea to set it at that volume before it distorts to be able to get the amps power. Now that this is figured out, you don't want to raise the volume above 46 since you can risk clipping. Head unit settings should be: EQ- flat, loudness off, bass boost-off SLA (sound level adjustment)- off (0) and subwoofer level- max to allow a strong signal to the amp. Also, if you are using a stock head unit, set the amp voltage switch from "low" to "high" Remember, if you do any adjustments after setting the equipment you have just defeated the purpose of this method.
 

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Discussion Starter #5
That's a good tutorial, but not sure if you are aware of the head unit settings prior to setting up the amp witha digital multi meter. When setting up a amp with a DMM you generally want to set the head units volume at 75% volume so if the head unit max is 62, the volume you have to work with is 46 or if your mid's/high's distort before this 46 volume it'd be a good idea to set it at that volume before it distorts to be able to get the amps power. Now that this is figured out, you don't want to raise the volume above 46 since you can risk clipping. Head unit settings should be: EQ- flat, loudness off, bass boost-off SLA (sound level adjustment)- off (0) and subwoofer level- max to allow a strong signal to the amp. Also, if you are using a stock head unit, set the amp voltage switch from "low" to "high" Remember, if you do any adjustments after setting the equipment you have just defeated the purpose of this method.
I o-scoped my headunit. The bass signal distorts at exactly 60. and clips at 61

And for the speakers. I can hear them distort at 57-58
 

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I o-scoped my headunit. The bass signal distorts at exactly 60. and clips at 61

And for the speakers. I can hear them distort at 57-58

Do you still have access to a silla scope? If i were you i'd work with the volume 56.
EDIT: if you do have access to it, i'd use that rather then a DMM.
 

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Do you still have access to a silla scope? If i were you i'd work with the volume 56.
EDIT: if you do have access to it, i'd use that rather then a DMM.
I do. But the oscope wasn't working last night. I had it plugged in and it wouldn't turn on
 

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So. I talked to the technical manager at RE Audio.

My amplifier is a hybrid amplifer. A class A/B plus a class D.

So the outer terminals on the amplifier are for a true Class D singal and will double the voltage to 63 like I wanted.

The terminals I had it on were technically a class A/B.
 

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if you have access to an o-scope, don't even bother with a dmm.
But that wouldnt matter in this situation. Becuase I used the wire terminals that are only half of the amps power.


And I didn't use my oscope that night because I had it plugged in. But it wouldn't turn on. I kept unplugging it and plugging it in. And it wouldnt turn on.
 

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But that wouldnt matter in this situation. Becuase I used the wire terminals that are only half of the amps power.


And I didn't use my oscope that night because I had it plugged in. But it wouldn't turn on. I kept unplugging it and plugging it in. And it wouldnt turn on.
you need to know where the head unit clips first. just trying to set it with some random number won't be perfect. i'm talking about if you really want to know what's exactly going on, o scope is the way.

if you're not at full voltage going into the amp, you'll probably never hit that magic number you want.
 

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you need to know where the head unit clips first. just trying to set it with some random number won't be perfect. i'm talking about if you really want to know what's exactly going on, o scope is the way.

if you're not at full voltage going into the amp, you'll probably never hit that magic number you want.
like i stated before. I oscoped the amps RCA's. THey clip at 61. And the headunit clips at 58 for the front stage speakers.

So i keep it at 56.

I can always turn up the signal to the amplifier on the headunit. It goes up to +6
 
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