Alpine type r's suck. SENSITIVITY RATINGS is what you should be looking at. For every 3 dbs of sensitivity, you double your rms wattage. Dont get a sub below 93 dbs of sensitivity/efficiency. DOES ANY1 SUPPORT ME ON THIS? Id say go with The Infinity's but the alphasoniks are good subs...they are made of kevlar thats very durable.
lol, wtf are you talking about sensitivity is the speakers reactance, yes it is true that if using the same wattage a speaker with a higher sensitivity will be alittle louder and were talking not noticable with the human ear and thats at like 1 watt. Say you have 2 speakers with the same RMS one has 82 and one 93 the one with 93 will take slightly lower wattage to reach the same volume as the other one with lower sensitivity and when i say lower wattage i mean about 20 so it barely makes a difference.
Jon, to put it lightly, your dead wrong. When it comes to subwoofers, sensitivity ratings are pretty much uselss. Aside from the fact that they really don't even matter much when you have as many watts as subs use involved, there are many different methods companies can use to get the sensitivity rating, and often times the numbers are flubbed.