i do understand what you are saying.. but maybe we are on 2 different pages...
I am referring to what the amp does when pulling power as you stated an amp will pull less current when supplied with higher voltage.
Take the AQ3500d, the original one.
It's rated to do -
5000w @18v (all rated at same THD level as i remember)
Now, let's throw efficiency away and say it's 100%
14.4v @3500w = 243A
16v @4000w= 250A
18v @5000w= 278A
It appears that the higher the voltage.. the more current it would pull BUT let's trun that around-
With the slight increase in current with a bump up in voltage, it appears that it "looks" like it pulls more current when in reality, it's just slightly more efficient...
Meaning... the amp should be pulling the same current regardless of voltage. It's just the higher the voltage, the higher the efficiency and the better output power it can produce.
The AQ3500d is also rated at 6500w @18v severe THD levels. You have to be pulling 300A or better to get that much power out of it so a decrease in current draw would be impossible.