narrow bandpass xover with zobel?

I agree with nearly everything said so far, with the exception of using iron core inductors. NEVER use an iron core in an audio circuit. Hysteresis distortion is very audible and quite nasty... If necessary, and if BENT on a passive system, use larger gauge inductors, to overcome the losses that are inevitable in inductors of that size. Also, I'll stop you (hopefully) from using electrolytic caps. Another bad choice you can make. OK in the woofer circuit, they MIGHT be acceptable in a mid circuit, but I recommend a poly or better "bypass" cap to improve their transient capability. NEVER use them in a tweeter circuit. Three-way is as far as I would ever go in a door. Ever. In a home system, I even prefer two way. The fewer the drivers, the better. I chose varying manufacturers drivers in my system, but my system (I will admit) is atypical (for a home system - VERY atypical for a car system). For example, my mids carry the brunt of the reproduction in my car, running from 200Hz to 4K. I knew what I wanted. I came up with a design, then I figured on my crossover points based on the -3dB points (on a polar plot), then I chose my drivers to fit the desired crossover points. I HEARTILY agree with avoiding a (especially passive) crossover point within the vocal band - your desired 1.5K right smack in the middle of it... <shudder> Off axis (which you are VERY much in a car) and unequal path lengths which are also inevitable, that is a VERY ill-advised crossover point. Very. Not to mention the HORRIBLE beaming that a 8" will be doing in the drastic off-axis situation you will be in. An 8" woofer will be a good 12 to 18dB down by 45°. ON AXIS, you can probably be OK, but you can't get that in a car. An 8" to a 5" at 1.5K WILL exhibit terrible sound power, EZPECIALLY with such a steep crossover.It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

Ok, I went there with the Iron core. Couldn't find a 8mh in an air core. If one was available from PE I would guess $75? The difference between the Electrolytic vs. the Solen Metal Poly is $59 each. My direction was toward how cost ineffective the x-over idea is. Does anyone other than Morel offer a 8" comp set?

Here's an 8 mH... And only $24 each! Madisound has Goertz Foil Inductors, too. You can get to 8mH with those... At a cost of ONLY $170.00 per side! Oh, sure... 1.6 ohms DCR, but who's counting!?! LOL (Just bein' a butthead...) However, if I were the one making the choice, I'd take DCR loss over hysteresis distortion ANYDAY. meicalnissyen, what we are all trying to tell you is that if you REALLY want that complex a system, by the time you spend enough money on passive parts, you could have spent all that change on a really nice active crossover. Granted, there is VERY likely additional complexity and cost in more amps, more wire, tweaking time... But you will end up with FAR better results for your car. I've done it, with an all active three way system in my doors, it wasn't easy, but my efforts (IMO) are rewarded every time I sit down.It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

Hmm, the OP must not have liked hearing these answers.  Oh well, maybe someone learned something from the exercise.Support the12volt.com

I just listened to a set of DLS Iridium components with 8" woofers driven by Genesis amplification.  VERY nice. Support the12volt.com

For a Kilobuck, I would HOPE so... It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

Plus it was in a new Jaguar.  Sometimes you do get what you pat for...Support the12volt.com

DYohn wrote: Hmm, the OP must not have liked hearing these answers. Oh well, maybe someone learned something from the exercise.

Not at all!! Daddy taught me that while I'm talkin, I ain't learnin !! I GREATLY appreciate this input And now I have more specific Q's regarding the 8" woofers flat on the deck, sealed 0.9cf enclosures extending into the trunk: by off axis, are we refering to the driver bouncing off a curved, angled piece of glass instead of being angled toward my leather recliner and residing in a carpeted room?? I dunno how to fix that, much, a car is a car I have been listening to the discussion carefully, and realize now I have been borrowing trouble and not stepping back to think THANK YOU I cannot drop much bucks (more) into this but I can use what I have much more correctly. The Xover points I take firmly to heart, with that in mind, how high can I run the woofer ? can I cross it at 4K , and make this a 2 way (plus sub) system?? I am using this driver: http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=290-312 it claims 45~7K another thought, with my cd5444, the front and rear outs will not see freqs over the nonfader set point, correct??? That being true, I don't need all these expensive chokes we have been debating,   and the issue becomes simply how low the 8" can go without gettin hit by the bump in the enclosure response curve. choices in the head are: 63,125, and 200   AND,... if it can run flat, high enough that I can put in decent tweeters and go two way or if I need to have a mid bass driver set. with most tweeters saying they go down to 2K, ... will a 2nd order crossed at 4K keep them safe? and would I reverse the tweet polarity to keep phase correct in that setup?