With some modifications, Maraschino monoblock boards can run from 12VDC. However, voltage drop from a BATTERY, with no regulation, over time will affect performance, and the power output will be quite low (gets lower as the batter discharges).
This is something I've heard with Danny's battery gear, and at least as far as I know has to this point simply been managed by keeping an eye on the output voltage of the battery and simply making sure the battery supply doesn't drop too far in to the not good zone while doing critical listening. I think this is part of why the bigger-is-better recommendations for batteries is out there; a single big battery can stay good to go longer than a small battery (or even a bank of small batteries hooked together). The question of whether one needs to go the extra lengths to try to squeeze even more love from a battery with additional parts I think comes down to the length of time one needs the battery to be in top form for a single listening session (because the battery can be recharged when the system is idle) and maybe the wear and tear on the battery as far as charging cycles/management (which I guess is an advantage - in audiophile terms of cost - to batteries because they are "cheap" enough to not be too worried about replacing).
A DC/DC assures no droop and allows a boost function, converting low voltage, high current to high voltage, low current. The rail caps hold rail voltage through peaks of higher current draw and even out the “load”. Handling the dynamics of music is another part of this puzzle.
So, with some mods, could one get a maraschino to run for say a few hours on a single big topped off battery? Without mods, could one put a bank of batteries together to get the needed voltage to get a couple hours of top-quality play time out of maraschino, keeping in mind limitations of voltage drop? If so, in someone like Danny's case - a person already invested in a pile of battery gear and batteries readily on hand - being able to try this out, comparing maraschino on batteries versus AC supply as a proof of concept from a subjective sound quality perspecive, would be possible without (or to see if it would be worthwhile) to go to the effort and expense to kickstart a more robust battery solution? Is maraschino circuit as-is sturdy enough to handle at least a little voltage drop over time from the power supply without causing big problems (as in breaking something) so that customers or folks who could get their hands on an amp to try out could check out batteries right now, even if a listening session was short, for themselves? It might also subjectively add data points to the influence - or not - of aftermarket power cords, power conditioning, etc. on maraschino on AC power as-is by having a quick way to just get the whole AC system out of the equation to see if there is a difference in sound?