So when trying to calculate your voltage, do you use ur ideal ohm load or the actual ohm load measured with a dmm? also say your amp does 1500 watts @ 1ohm, will it still be putting out that much or close to after impedance rises (say to 1.4ohm)?

i have always been told that if u are running ur amp at say 2 ohms then to use that 2 ohms when setting ur gains.

welll for starters don't worrry about impedance rise unless you are going to be burping!!

as for calc your voltage i just use the ideal ohm load b/c as your coils get hot and cold the ohms will change. so if you have d2 sub you can calc your voltage using wither 4ohm or 1ohm load! but hey take a look at this chart! at 1500rms from 1-1.4 oohm there is 10volts difference!

so if you wnat just add like 5volts break the difference! and see how it goes!

very informative, thanks!

Keep in mind that impedance is also heat and frequency dependent. So it would be impossible to choose any particular impedance based on measurements as the measurements will be all over the place depending how and when you measure.

Some people don't like the DMM method. But I think it sets a reasonable baseline for someone not familiar with gain setting/structure.