PLM: Calculating the necessary gain setting in controller

Question

How would I calculate my gain setting in Lake Controller?

Answer

Gain in dBu is related to voltage by:

Gain = 20 log ( voltage/ 0,775V )
0 dB is defined with 0,775V in a 600ohm load and you shall find the gain in relation to that.

Ex. 1000W and 4 ohm = sqr( 1000 x 4 ) = 63,24V  ( ohm law = U = R x I and P = U x I that gives you that U = Sqr ( P x R )

So the amp must deliver 63,24V into the 4 ohm load and you will have 1000W power! Gain will be = 20 log (63,24V/0,775V) = 38,23dBu ( total needed gain to get the 1000W)

If the amp gives you 26dB gain you will need 38,23-26dB = +12,23dB to get the 63,23V out of the amp! ( so the controller must deliver +12,23dB on the output).


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