Head unit output -- setting amplifier gains

[Patthehat033 10+ year member]

So my head unit has 2V pre-out puts and my CDX-20A can handle up to 8V.

I am planning on running 3000 watts... only a couple hours from being done installing the subwoofer. Can I achieve 3000 watts with the 2V output, or will turning the gain up to compensate for the low input voltage distort the signal?

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[MutantDreams 10+ year member]

It will clip the signal, but how bad really varies. I think your best bet is too buy a line driver. Now dont just throw it in there, it might destort it even more. But it should put out a good sound, even at 2v

 

[Patthehat033 10+ year member]

It will clip the signal, but how bad really varies. I think your best bet is too buy a line driver. Now dont just throw it in there, it might destort it even more. But it should put out a good sound, even at 2v

How many watts can I run with a 2V input?

 

[JoeK 10+ year member]

The purpose of a gain is to adjust to the line voltage. Most amps go down to 0.2V, youll just need to crank that gain some more than you would a 4V etc

 

[Patthehat033 10+ year member]

The purpose of a gain is to adjust to the line voltage. Most amps go down to 0.2V, youll just need to crank that gain some more than you would a 4V etc

But can I obtain 3000 watts without distorting the signal? The amp is capable of producing 4000 watts.

 

[JoeK 10+ year member]

But can I obtain 3000 watts without distorting the signal? The amp is capable of producing 4000 watts.

You dont understand how gain works. What does the other number on the gain knob say?

 

[Patthehat033 10+ year member]

You dont understand how gain works. What does the other number on the gain knob say?

The gain knob just shows Min. and Max. it does not show voltages. On the internet the specs for my amplifier say that it can take up to an 8V input voltage. My head unit only has a 2V pre-out voltage.

 

[JoeK 10+ year member]

But theres a minimum figure as well. Mine for example has a range of 0.2V-6V iirc

I highly doubt 2V is under the limit for that amplifier.

 

[Patthehat033 10+ year member]

RMS Power @ 14.4V DC:

1 x 25W @ 4ohm

1 x 3600W @ 2ohm

RMS Power @ 17V DC:

1 x 50W @ 4ohm

1 x 4000W @ 2ohm

12-17V Power Input

Frequency Response: 10Hz-350Hz

0.2-8V RCA Input Voltage

Short/Overload/Thermal/Protection

LCD Display of Temperature and Voltage

24dB Variable Subsonic Filter

24dB Variable LP Filter

0-18dB Variable Bass Boost

Remote Gain Control Module

CDX8A/CDX10A is Bridgeable with another CDX8A/CDX10A Amplifier

RCA Line Output

2 Ohm Stable

Dimensions: (LWH) 26" x 12.25" x 2.5"

0.2V is the minimum but wouldn't I need a certain amount of pre-out voltage to pull 3000 watts from the amplifier. I doubt I could pull 3000 watts by pushing 0.2 volts lolz.

 

[momofx 10+ year member]

0.2V means that it will take at least an input of 0.2V to achieve its full output. Almost every amp company realises that most headunits cannot even put out a clean 2V signal so therefore they use a wide range voltage input like this. YES you will be able to achieve full output but you need to MATCH your amp gain with your head unit!

If you are not firmiliar with setting gains on a high power amp, please get someone professional to do it or at least get a dd-1 if you do not know how to use a scope. DD-1 is pretty close to a scope.

 

[RicksI30 10+ year member]

To answer your question YES you can achieve your amps full power with a 2v pre out.

 

[LosIsATool 5,000+ posts]

That's a old school Cliff designs lol. He's going to smoke it if he don't even know something this basic

 

[maylar 10+ year member]

So my head unit has 2V pre-out puts and my CDX-20A can handle up to 8V.
I am planning on running 3000 watts... only a couple hours from being done installing the subwoofer. Can I achieve 3000 watts with the 2V output, or will turning the gain up to compensate for the low input voltage distort the signal?

Preout voltage has nothing to do with clipping or distortion. As mentioned by others, you can reach full power with 2V. You can also drive the amp to distortion with 2V if you don't set the gain correctly.

 

[JoeK 10+ year member]

tldr shut up and set the gains right

 

[Patthehat033 10+ year member]

Well the guy who built my sub box told me that I would only be able to achieve 1/4th of the power of the amp since it was only putting out 2V, which is what made me make this thread.

I just hooked everything up and I seem to have some problems. My amp keeps going into protect from low voltage (I believe). I am running 2 AlphaCell 100AH batteries in the back of the trunk, a 200 amp Mechman Alternator, the Big 3, and 0 Gauge all the way to the back. Yet, even with the gain slightly over half on the amp, my radio starts dimming etc.

It doesn't even sound like its pushing over 1000 watts.

Any ideas?