Reducer / converter vs 12v accessory battery

[beachguysc]

I currently have a 4x12 lead acid battery set up with 20 amp 48 to 12v converter for lights and small other small draws. It is hooked up with a fuse block to operate with the key. I have a separate 12v battery in the back for my stereo ( 2000w class D amp, 10" sub in box, 4 polk speakers and bluetooth marine player). I am switching to a single 100ah (500 peak) Lithium battery, and bypassing the OBC. I wanted a separate 12v for stereo because of the limits of the 4x12 running time. But with this new battery system, Can I run two 48 to 12v converters? with 2nd converter being 30 amp dedicated to stereo and not keyed? or should i just get one big 40 amp converter. Or just leave dedicated battery.

[kgsc]

If you already have a dedicated battery for the stereo I wouldn’t touch it. That amp is going to pull some current and worse case the stereo quits working until you can charge it. If you go the converter route when it kills the battery you don’t get home.

[beachguysc]

Originally Posted by kgsc

If you already have a dedicated battery for the stereo I wouldn’t touch it. That amp is going to pull some current and worse case the stereo quits working until you can charge it. If you go the converter route when it kills the battery you don’t get home.

Thanks. That is definitely a consideration for my current setup. But it will not be as much with Lithium, because I rarely go more then 10 miles round trip. What I'm hoping to eliminate is having to hook up two chargers every time I come home. but I've done it this long. It wouldn't be the worse problem to have

[Volt_Ampere]

Yes you can run multiple 48 to 12V converters and you will be fine if you keep the current demands under their ratings. No need for a separate battery IMO.

[CP241]

Assuming your amplifier is 2000w peak, I’d estimate around 1000w RMS. Which equates to around 84 amps current draw.

Music is dynamic… so it’s not going to always pull that much, but capable of 80-100 amps (or more) current draw. Look at the fuses on the side of the amp itself and add them all together. If you aren’t cranking it, I’d still estimate it to pull 30-40 amps at a moderate volume level…

Your current demand is going to quickly exceed the capabilities of a converter. I’d stick with a separate 12v battery for the audio.

[TheCartBoy]

If you have the space, install both chargers in the cart with a heavy duty extension cord, that way only 1 plug to use when you get home.

[beachguysc]

Originally Posted by CP241

Assuming your amplifier is 2000w peak, I’d estimate around 1000w RMS. Which equates to around 84 amps current draw.

Music is dynamic… so it’s not going to always pull that much, but capable of 80-100 amps (or more) current draw. Look at the fuses on the side of the amp itself and add them all together. If you aren’t cranking it, I’d still estimate it to pull 30-40 amps at a moderate volume level…

Your current demand is going to quickly exceed the capabilities of a converter. I’d stick with a separate 12v battery for the audio.

Thanks. I am going with the separate battery. which brings up the question of amp hours and lithium vs sla. I'm definitely going with Lithium. But I have a questions about amp hours when going to lithium.
Previously I had two 35ah sla batteries in parallel. But I would never run it below 50% since I didn’t want to kill them. So did I really even have 70ah combined? I’m asking because I would like to replace these with one 50ah lithium battery. Would this give me more actual runtime capacity since I can run it down to zero without harming?