i just purchaced 4, 8" ma audio xl compitition subs(MA800XL) 400 watts RMS and 800 max. their dual 4 ohm voise coil each.can i run them all together with one amp. if so how many watts does my amp need to be and what ohm should it be stable at. if i need 2 amps how many watts should they be and what ohm should they be stable at. and should i run them series or paralel
Yes these subs can be run all from one amplifier. You will need to wire them is a series - parallel circuit. It will give you a load of approximately 2 ohms. The amp you need to look for will need to be designed and enginnered to run at a 2 ohm mono load, not stable to a 2 ohm mono load. Here is a description on how to wire your subs.
(1) flip sub upside down on counter. wire 1 voice coils positive to the other voice coils negative. This leaves you 1 positive from 1 voice coil and 1 negative from the other voicecoil. This also makes your sub an 8 ohm speaker. Repeat for all other subs.
(2) Now hook all the remaining unused positive leads together.
(3) Do the same for the negatives
This will give you a load of approximately 2 ohms in mono. You should only have 1 set of wires to go to the amp.
To double check the series - parallel portion of the wiring, have a look at the series - parallel calculator on this site. You will have to derive things from there as it does not actually have the calculator that you require, it is a combination of both. Ignore the fact that you have a dual 4 ohm voice coil sub, think of it as a single 8ohm sub. Punch the values in on the parallel calcultor for 4 subs at 8 ohms and it will show you the load.
Get yourself the biggest amp that you can afford that is stable at 2 ohm mono, that is going to give you as much rms power as possible or is within your budget. I would have a look at the Rockford 1500bd amp for one example, there are many more as well.
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