A lot of amps and a lot of electronics run on DC… most of these units have a Ac to Dc converter for this. What most are doing is taking out the AC part, and hooking directly to DC.
If you have products that you want to try doing this with, open up, find the circuit… clip, solder and go! Make sure you add fuses too. Lol.
Lot of time you can find the power adapter and see what that does example 120Vac to 12.5 or 14.5 VDC.
Batteries are 12.6-12.8 resting In good shape. AGM is just the most common, next to lead acid. (absorbed glass matting) many company’s use this technology, with different glasses and more. lithium batteries are not ready I don’t feel for audio yet. But I’ve been playing with them quiet a bit. It’s a powerful charge, in a small pack! If we could get this tech better, it would save space and weight! Trust me, a ton… put it this way, I can power a motorcycle off a batter I can fit into a headlamp housing. But introduce cold weather, or ripple DC charging and you’ll smoke a Li battery.
Ac power source goes above and below the 0 volt line 60 times a second. (A cycle) This induces a hum into most audio systems being its powered by this 120Vac 60Hz hum. You hear this in most fluorescent light Lol. So DC is a direct current… it does not alternate above and below the 0 volt line. It goes directly to what ever voltage (this case 12.6 let’s say) or what ever your output is from battery. Some electronics are 24 volts some even 48 volts. Rather then a step up transformer, I would add more batteries till I got the desired voltage level.
Transformers work off electromagnets and windings. Another noise item.
Now, you’ll need to have these recharged… and the battery charger is just a power source in reverse.. it’s takes the 120Vac and drops changes through bridge rectifier, voltage regulator chips an capacitors for filtering and more to produce 12vdc. Having this hooked up when not listening to music is best… cause otherwise you can introduce ripple DC which could be heard while. After all, we are taking AC and changing to DC with 4 diodes. Lol.
So, In essence running on DC does a few things.. 1. Brings on a whole science experiment. 2. Kills the 60Hz hum right off the bat. 3. A lot of line voltage sources are dirty power.. not filtered, no power surge protection… can cause issues for higher end audio. Any noise really.
Running off DC is cleaner in Theory. If you want to take it to this level… please understand that this is not a inexpensive solution to do properly. But a lot of fun. GL.
Many around here repeat things said, and really don’t have the knowledge to answer most of this. They just say, because it does, or repeat words someone else’s does not have the school for… even those that do can sometimes goof it up. Unless your really good with this stuff, I would ask and look around quiet a bit before starting.
Then again, as above… What do I know!? Lol. Even going to a real school, I still know nothing. So, do a ton of research.
Take a look into this for your self and do some low level experiments.
