Agreed. A budget is the most important factor to look at. Let us know what your final price range is. There will always be better products that cost more so pick your range and try to stay with it.
WWW.cardomain.com has a nice price on Infinity subs and a kenwood amp.
The Infinity Kappa Perfect 10 VQc has slight cosmetic damage but is priced at $169 opposed to $249.
http://www.cardomain.com/item/INFPERFECT10VQC
This is more of a spl sub opposed to a sq sub. I have heard them and they are pretty accurate and would give a decent overall sound between music. A plus with this model is that it offers a variable Q so the sub can be fitted to a wide range of boxes. This would be ideal if you were going to just buy a box and not custom fit one.
The Infinity Reference 1030w is priced at $51 dolllars and is a very nice sq sub.
http://www.cardomain.com/item/INFREF1030W
If you are looking to save money and direct the subs toward rock I would suggest two of these. The smaller surround, lower wattage requirements and high sensitivity make for a faster response time for drum rolls. The reason I suggest one is that this sub will not get as loud as the other model. Since rock music has higher frequencies you will want to compensate with two subs and more wattage.
The kenwood Kac-9102D is a decent mono (single channel) class D sub for 299.
http://www.cardomain.com/item/KENKAC9102D It produces 500 watts rms at 4 ohms and 850 watts rms at 2 ohms. This would be more than adequate to run one or two (if you want to upgrade) of either of the infinity subs. There is a low pass crossover and subsonic filter. Something you must have if it is not on your HU. For the price, this is a very nice amp. Keep in mind that if possible you want to focus on the amp more than the sub. Just try to stay away from a 150 dollar 1000 watt amp.
If you like the Infinity reference (SQ sub) then I would go with two 4 ohm singe voice coil models. That would give your amp a 2ohm rating and push 250 watts over the subs rms. That would help to give more push to some of the lacking frequecies in rock. If you can't afford two then one single 4 ohm voice coil would still be pushing more than the rms. You could try it out and add another if you don't like it.
If you think the perfect sub sounds good then one of the 4 ohm single voice coil models will probably fit your needs. This sub is very close to my current sub. I listen to blues, jazz, and rock for the most part and two would overpower most of the mids.
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