Audax/Vifa two way first order project

[AllCaster]

New to board and DIY(for speakers). Have read Dickason's Cookbook.
Looking for a father and son project; woodworking, finishing, speaker assembly, soldering, and a Hi-Fi project for high school, college, and beyond.
I would like to make a speaker similiar in appearance to the Meadowlark Shearwater, a transmission line or vented, using an Audax Aerogel AM170Z2 6-1/2 and the Vifa XT25TG30 or Seas Excell T25CF001 tweeter. First order, XO at over 2500 Hz. The cabinets I can do. Drivers about $300. XO with top grade components, minimilistic. I picked the drivers because I have an older pair of VR4s, and I believe Von Schweikert is now using the Audax with Vifa/Seas tweeters.
Any help, based on experience or CALSOD/LEAP would be appreciated.
Thanks

[Grahamt]

Welcome, speaker building is a fun hobby.

I'd like to make some suggestions. The Audax Aerogels look great but Audax is pulling out of the DIY market so replacement drivers will be hard to get. Although the XT25 has a low Fs, apparently it doesn't like to be crossed over low because of high distortion and from what I have read it is not suitable for 1st order in that range. Also, for first order you will need to offset the drivers for the different horizontal centers as mentioned in the Cookbook.

Most of the time, copying someone else's design or building a kit is recommended for the first time builder, but best of luck with whatever project you do.

[AllCaster]

Grahamt, thanks
I was wanting to do a slanted driver, like Theil, or for this project like Meadowlarkaudio.
Is crossing the Vifa at over 2500, really crossing it over low? Would the Excell T25 work OK? Has anyone already done a DIY like the Meadowlark Kestrel 2 or Shearwater?
Joseph

[Grahamt]

There are many people who have tested the XT25 and it has a reputation as being difficult to work with. It also has a very small Sd which may be a reason for the high distortion at lower frequencies.
IMO 2500 would probably be fine for fourth order, but it is too low for what is basically a 3/4" driver with a 1st order. Not enough attenuation.

I have done some crappy first order projects but they were with big compression drivers that can take the power and I still crossed them over high. Usually people pick a robust driver like the Morel offerings. I dont know if the Seas tweat would work. Look for some clone audio sites, maybe they have something you are looking for.

If you want to try something new, www.creativesound.ca has a new full range driver, the wr125s. You could try a first order with that and crossover any where you wanted.