The problem with doing this is energy consumption. My MacBook Pro, depending upon the software running, can consume nearly 7.5 amps through a 400 W inverter. Even my PC based laptop pulls upwards of 6.8 amps when run straight from the DC source.
It is not a problem, the way I have described it. Each person will arrive at a solution from their own current situation, and of course some of the details are not needed or wanted by some.
When I started off with a PC, it was as stated on the assumption that you already have one or plan one for navigation use, which is quite common. In that case you must already have been through the Amp calculations. Of course, if you do not use a PC onboard, you would not acquire one only for audio or video use.
Power consumption was crucial in the system sketched. It means that you can hav
e a full-blown setup with audio and video when power is available, either on shore power or for use with a generator. When on basic 12V, you have the lowest consumption possible
, using only the iPod with the radio setup. Also, you could get quite some mileage out of the MacBook Pro running on batteries. Flexibility is key.
I absolutely agree that running a PC via inverter is a lousy idea, as much as running any
media component via the inverter. My own inverter (Mastervolt) would already draw more than the appliance. If you were
to plan a system based on the inverter, better ditch the battery PC altogether and try a Mac Mini on mains voltage. The current model is promised to draw 13W on idle, and 110W at maximum draw, pretty modest.
For the record, I run a system approx. as described, and it is a pure joy. With Polk Audio speakers in cockpit, the sound is sweet.