Voltage multipliers only work with AC. If you are trying to create the correct DC supplies for a mixer, you need DC converters for the required voltages. +15/-15V is typical (possibly only +12/-12V), plus +48V for phantom and sometimes a low-voltage rail to drive LEDs or logic circuits. The VAC input would be dropped across a +15/-15 transformer, then regulated and filtered. The +48V would be multiplied off of the +15V rail, and the low-volt supply is usually dropped from the +15V too, unless there is need for high current on the low voltage rail, in which case there will often be a separate secondary winding on the transformer to generate the low voltage rail.
Converting this to DC would require at a minimum the +15/-15V converter (there are off the shelf solutions for that) and +48V (which has to be built with components--I published one such circuit last year). Also note the unit's listed power consumption of 8W--that's probably a maximum, and typical consumption is probably much lower, but that is a huge load for a battery so you'd need to pack plenty of power.
Thanks for the tips.
No answer from tech support, and no luck getting a schematic yet, either.
The DC power doesn't intimidate me, but a quiet, switchable P48 would be new territory.
I usually lug 140WH with me, so another 50 wouldn't be noticed
I want a schematic before I bust out a $bean on an experiment!