I have two Infinity Kappa 100w.dvc subs (the ones with green cones) in a sealed enclosure, each with their own airspace. According to the manual that came with them, each voice coil is rated at 225W RMS (two per sub) with 4ohm nominal impedence per coil. I wired the coils on each sub in series (8ohms per sub) and plan on running them off of a mono amp (4ohm total impedence at the amp). Two questions:

1: To find an amp that will match this setup well, do I just add the watts together for all voice coils? This would give me 900W RMS, which seems pretty high. I'm thinking that the wiring setup may have an impact on what wattage I should go with on the amp.

2: Should I calculate each coil at a lower handling capacity due to their age, like 200W each instead of 225?

Or if you think there is a better way to wire these all up, let me know.

 

You've got it right.

1.) The 4 VCs will "share" the power, dividing it equally.

2.) That won't matter. 225W is fine.

BTW, not that it matters a whole lot, but it would be less wire running to the amp if you hooked each VC in parallel on each speaker, then ran the 2 speakers in series to the amp.

Again, that's only if that matters to you.

 

225 watts per coil is what the coils maximum thermal load is. Your box will dictate more as to how much power you need. The larger the box the less power needed to make the sub reach its maximum performance. Im not saying don't get a 900-1000 watt amp but just that its not always needed.

 

9177: Each coil is rated at 225W RMS, not max. I'm note sure how this equates into thermal load; could you explain a little further?

AJ: I can still run each sub in parallel and only have one speaker cable running from the amp to the sub box.

 

I know.

Bad joke. :lala:

 

When a speaker is rated for power it is rated buy what the coil can handle electrically in you case it can handle 225 per coil. the company guarantees that with 225 watts per coil or less that you will not burn the voicecoil (this dose not mean that the coil can’t handle more power just what the company will warranty) . But that does not mean it takes 225 watts per coil (450 watts per sub) to make the sub perform to its full musical potential.

An example would be if you have them in a 1 cuft box each it may take a full 450 watts per sub to make the subs reach it full musical potential. the upsides to smaller sealed boxes are high power handleing and the ability to have slightly higher spl. If you had them in a 2 cuft sealed box you may only need 250 watts per sub to reach the full musical potential of the subs. The upside to larger boxes are the need for less power and it makes it easier for the subs to produce lower notes (lower f3) but this also usually lowers the output capabilities of the sub.

Me personally i would rather have on 12 in a large sealed box vs. 2 12s in smaller sealed boxes. but lately i've been more into ported boxes which is a whole different ball game.

 

I'm using a smaller box to get a flatter frequency response. I don't mind how much power it takes to run them optimally, I just want to know what IS optimal. I'm looking for SQ first, then SPL.