Need some ADVICE please!!

ItsMixedUp Newbie
Mar 7, 2021
United Kingdom
So I was gifted a sub off a mate which runs at 250W @ 4 ohms and just bought an amp, the amp is a Juice Ja1201d 1200W peak (I don't believe this rating lol), rms 480W @ 1 ohm, 380W @ 2 ohm and 225W @ 4 ohm. It has a 50A fuse on it.

I was trying to do some math to figure out what fuse I needed from the battery but I am struggling to find out what figure to use. If I use the supposedly peak power figure I do 1200/0.8 then 1500/13.8 is 110A which is way above the 50A on the amp this is why I don't believe this rating. If I do the 480W @ 1 ohm then this works out to be about 43A which is closer to the 50A on the amp.

Should I buy a fuse which is 30% bigger then the one on the amp? (this is what it recommends).

Also I just bought some 8 AWG OFC tinned wire for the power and ground and I am starting to feel I should have bought some 4 AWG wire instead :/.

My questions are will I get by with this gauge wire for power and ground and what fuse should I buy??

Sorry for this, this is my first install and am unfortunately really struggling lmao.


Kickstand Well Known
Jan 1, 2021
Maple Ridge
Don't listen to that peak power marketing BS
RMS is the only thing you should be paying attention to
If your running a single voice coil 4ohm sub then 225 watts is all your going to get out of the amp.
Which lines up with the rating on the sub so ...
If you were running it at 1 ohm I would say get a 75 or 100 amp fuse but since your running it at 4 ohms your not drawing as much power.
If it was me I would go with a 60 amp fuse but you can go higher if you want.
You can probably get away with that 8 gauge kit but I don't recommend it. 4 gauge is your best bet.

If its your first install the remember to run the power and the RCA's on separate sides of the car
Keep your ground as short as possible, clean the paint off around the ground and don't just screw it into the metal
Find a bolt that attaches to the frame of the car
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ItsMixedUp Newbie
Mar 7, 2021
United Kingdom
  • Thread Starter Thread Starter
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Thank you very much for taking the time to reply and I really appreciate your advice.

I will go with your recommendation of that fuse and have just contacted the company I bought the wire off to hopefully change the wire to 4 AWG because I don't think they have shipped the wire yet, hopefully they haven't lol.

I will make sure to do those things, it makes sense to sand off the paint for a better connection and I presume seperating them is to deal with interference? I will definitely do that though, thanks for the advice!

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