Originally Posted by
Smitty
No.
More detailed: What frequency are you asking about? From 70 to 80 Hz the Kicker is predicted to be 3 db louder but the Qtc is high so it begins to roll off quick and the ID will begin to best the Kicker as you go lower in frequency. In this situation, the Kicker exceeds it's mechanical limits just below 60Hz so you if you run 250 watts below that number you can bottom out the sub. You will have to turn the volume down and keep the sub below 150 watts. At this point its about the same volume as the ID sub but the ID sub has a much better response and low frequency extension. The ID sub has enough excursion to handle 250 watts but the voice coil can only handle 175 before the heat gets too high. During music playback it should not be an issue. Low bass tracks and sine waves, you could damage the coil but only at full tilt. Either way, both subs are going to be handling roughly the same wattage just limited by different means.
Not even close in my opinion. I doubt you were speaking with an engineer. It was most likely a rep and what does he consider perfect? There is a video of a Kicker rep at a SEMA show saying anything below 40Hz is a waste so they cut it out. He may not have meant it that way but it sure seems like he doesn't quite get what he's talking about. I'd be willing to bet most of the companies that produce budget lines have engineers who regularly want to bang their face into a wall when the boss tells them to design a $50 dollar sub and make it have "Moar Bass!". Response and sound quality are generally the last consideration in that realm due to the targeted buyer. They are designed to be entry level and get people in the door while knowing they will eventually upgrade.
I do not use the terms sloppy or peaky when describing enclosures unless they are pure crap, then sloppy may apply. Peaky to me means a "One Note Wonder" like an SPL guy may build. Many experienced people may use those terms when attempting to describe system Q to a novice in an attempt to get them to understand. Experienced people still argue over transient response and damping. The speaker engineers that understand it can have trouble relating it to even experienced audio enthusiasts and even more so to the novice. When a sealed enclosure gets above a certain size it begins to perform much like an infinite baffle system. The rules are different in IB vs sealed but to say it is sloppy is wrong in my opinion. One of the best sub systems I ever heard in a car was an IB setup and it was gorgeous sounding.
The amount of subwoofer systems I have built is still down in the double digits over the last 30 years. I still learn with each new system and experiment I do. My recommendations are based on my experience. You need to do the same. I feel you are worrying too much about the small stuff. The best way to learn is to read the resources we have posted and experiment. Then you will know the sound for yourself. Our recommendations are to guide and get you started, not nail down perfection. If you get the Kickers I feel you will like them initially then quickly outgrow them. The CTX108 is an older model that still works well and can stay with you longer on your car audio adventure with good sound quality. The original DVC version we talked about is a newer version. It will handle more power and be more flexible but is more expensive. It is a driver you will keep for a long time. FWIW I still have an old school JL Audio 12W1 from 1991. It is in a sealed enclosure under my desk powered by a Dayton rack amp. I'm listening to it as I type. I even have a bare 12" Infinity home audio driver laying in the corner I have been meaning to measure the TS parameters on for weeks. I like to tinker and experiment then put what I learn to use. Based on the questions you have asked, you may do the same one day with your old equipment...or even new equipment. The ID subs work square in the middle of your box. This gives you a lot of room to experiment with stuffing and blocks. The Kicker and Rockford subs will work but each are at either end of the spectrum and will drastically limit the tuning ability of your box.
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