Math for input sensitivity adjusments

[JessyBoy86]

I'd like to know if i can simply use Math to figure the input sensitivity setting i need on a amp according the max Voltage of a DSP.

I'm just trying to get in the ballpark with that....i know i must keep monitoring the system and use a multimeter but,

Say my DSP gives 2V max. Input sensitivity on the amp goes from 5V to 200mV.

Sub is 1000w rms at 1 ohm

Amp gives 2250w rms at 1 ohm

With the equation V=rootsquare(1000*1) i figure that i need around 32V at the output of the amp.

With the same equation, the max Voltage on the amp for 2250w at 1 ohm is around 47V.

If i set the sensitivity to 5V, with the Gain equation Gain= Vmax/sensitivity....i have a gain of around 9.5.

So, with 2V input times 9.5 i would get 19V.

Since i need around 32V, i figured i'd have to set the input sensitivity around 3 to get a gain of 15.8.

Am i right or completely off the map ??

Say the DSP gives 5V max and i keep the same amp. With 5V in on the amp and sensitivity at 5V, i would get 2250w, wich is too much for my sub. In this case, do i have to lower the channel output level of the DSP, or adjust the sensitivity of the amp using a lower master level on the HU ?

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[Chris McNeeley]

To my knowledge, at least how i set up my ampere dsp, watts X ohm and sq root of that, and i always adjust the amp once the dsp is tuned you shouldnt adjust anythimg at the hu.

 

[JessyBoy86]

To my knowledge, at least how i set up my ampere dsp, watts X ohm and sq root of that, and i always adjust the amp once the dsp is tuned you shouldnt adjust anythimg at the hu.

When you say ''once the dsp is tuned''.....you mean crossovers points and slopes and time alignment right ? I heard that the EQ must be flat to 0 when you wanna adjust the amp...

 

[JessyBoy86]

you shouldnt adjust anythimg at the hu.

Well, didn't think of that, i simply need to adjust the input sensitivity on the dsp...i don't have all the hardware now, just wanna do my homeworks before buying anything.

Other question, since i will control the master level using the remote controller of the DSP, at what level should i set the HU to set the DSP afterward ?