New Member, site to buy components?

Get to know these two online speaker builder's sources:  http://www.madisound.com/ and http://www.partsexpress.com/

For your first build, which can be a successful learning experience, I'd suggest using some of the lower-priced drivers you'll find on those sites.  Look through the buy-outs and closeouts, or other specials.  Also, look at high efficiency midbass drivers so that you can get a good system up with that available power.  Even some of the lower end Goldwood speakers at PartsExpress might fit the bill in that department.  And the Dayton brand is of higher quality than the price implies.

For the crossovers, look at PartsExpress'  Dayton brand for a good quality at less-than-audiophile pricing.  Dayton polypropylene capacitors, Jansen 18 or 20 gauge coils, and audio-grade resistors from either source can be had for reasonable pricing.  Wiring the crossover together:  I learned that using the pre-made crossover boards were more pain than pleasure, and now make them to fit MY plan...not a pre-arranged layout.  Use some high quality primary hookup wire to link the components of the crossover...I use 16 ga. silver plated teflon coated primary wire from http://www.hndme.com/storeteflonwire.html for crossover construction, and regular 16 ga.primary hookup wire for the runs to the drivers.

Here are some speaker design programs you may not have found yet:

http://www.pvconsultants.com/audio/frdgroup.htm  Of these, I use SPL Trace to copy the manufacturer's response graphs, which then are imported to the design programs.  Unibox helps you design the enclosure for the woofers.  Speaker Workshop will enable you to design the complete crossover.  These programs will share common files, so you can move results of one to another.  This is an appproach that is quite accurate and will allow you to build a network without having all of the equipment the pros use.  See http://www.rjbaudio.com/Audiofiles/FRDtools.html

And some very handy online calculators:

• http://www.mhsoft.nl/spk_calc.asp#top
• http://www.1728.com/pythgorn.htm
• http://www.troester.org/ls/lpad.html
• http://www.easysurf.cc/cnver7.htm#inmil3
• http://ourworld.compuserve.com/homepages/Bill_Bowden/r2.htm
• http://www.carstereo.com/help2/Articles.cfm?id=31

Good luck at OU.  I grew up not too far from there on the WV side of the river, and my son is graduating from that other Ohio school in Columbus this year.  He's a designer (industrial), so I foresee some collaboration with him on some things in the future.  I wish I had the foresight to get into something like you are doing at that time of my life.  Gold mining just didn't pan out  ;)

I'd suggest this one instead, as it is a 4 ohm driver designed for auto use.  Use one 4 ohm woofer with one 4 ohm tweeter on each side for your car's front soundstage for stereo sound.  The crossover will control the impedance when you have it designed properly.  The drivers connected via crossover are not in parallel, they are controlled by the crossover.  Use the impedance for each driver that you want as the final network impedance, e.g. 4 ohm for car, 8 ohm for home....and variations thereof.

The response graphs for all of the Dayton drivers are given, so they are easy to work with using those programs I told you about.

Take your time learning...take your time designing...build your system...listen and enjoy.  You will know the answer to that question after listening to yours and to other's systems.  Vague?  Sure.  The answer could go either way.  You will know right away that the actual components you are working with are superior to the ones in the premade crossover, but you don't know as of yet how to put them all together the best way.  You can still ruin the sound even if your crossover is worth 20 times more than the premade one...if you do something wrong.

You have to start somewhere if this is to become one of your hobbies/ passions.  This sounds like a good time!

I'm sure Steve will add his input, but my opinion is you can approach system design from any angle you want.  If you want to try a specific woofer or tweeter, then you build everything around that.  If you want to try a different crossover topology (like Bessel VS Linkwitz VS a series crossover) then you can design that first and choose drivers to fit.  Or, you can start with a desired system outcome, like "I want to be able to play undistorted at reference levels (110db) with a 50-watt per channel amplifier," then choose speakers that will achieve this and design the crossover to match them up.

My usually approach is to start with a specific speaker I want to try, whether it is a woofer or a tweeter... and once in a while I'll have both in mind and devise a system to make them work together.    I just finished a home theater subwoofer system for a friend that was designed to meet a specific system performance goal, and I'm now working on a center channel for a client that uses a specific speaker to match his existing stereo main set.

Speaker system designing and building is an additive (and can be very expensive) hobby, but it's also one that can be turned into a profession if you are good at it.