As seen on X and YouTube:

Designed for use with the Tang Band W3-1876 woofer, and the GRS A25-2T tweeter.  Usable overall bandwidth of 50Hz - 16kHz in the nearfield; ideally against a wall.

Tang Band W3-1876S 3" Subwoofer:
https://www.parts-express.com/--264-909

GRS A25-2T Tweeter:
https://www.parts-express.com/GRS-A25-2T-2-Textile-Dome-Tweeter-Replacement-for-Dynaco-A25-292-469

M3 x D5 x L4 Threaded Inserts:
https://www.amazon.com/dp/B0CS6VZYL8

M3 Screws:
https://www.amazon.com/dp/B0BMQ5Z96H

M4 x D6 x L6 Threaded Inserts:
https://www.amazon.com/dp/B0CS6XGMFD

M4 Screws:
https://www.amazon.com/gp/product/B0BMQ4WV1V

Hilitchi Binding Posts Terminals:
https://www.amazon.com/gp/product/B07PFMD1N2/

Reusable Adhesive:
https://www.amazon.com/dp/B001FGLX72

Recommended printing settings:

PLA is okay; PETG is better.
At least 4 perimeters / walls / loops all the way around.
At least 40% gyroid infill.  (Higher is better.)

Disclaimer:  This is an acoustic model.  As such, it does not scale, nor is it compatible with drivers other than the ones specified.  Scaling / incorrect driver(s) will result in significantly diminished performance.

Assembly notes:

• Use JB-Weld (or a similar two-part epoxy) along the tongue & groove joint.  Be sure to align the two halves carefully before curing, as the tongue & groove interface allows some wiggle room.

• Use M3 threaded inserts / screws for the tweeter, M4 threaded inserts / screws for the woofer, face, and the underside of the enclosure.

• To achieve a proper air seal, a gasket of reusable adhesive needs to be formed around both the woofer and the tweeter, as well as the forward-facing gasket landing that seals to the face of the enclosure.

• Once the speaker wire has been snaked through the hidden channel, use a small blob of reusable adhesive to seal around it.

Wiring / DSP / amplification:

• The A25 Micro is a bi-amped speaker; it requires two channels of amplification:  One for the woofer, one for the tweeter.

• The woofer requires a high-pass filter of 50Hz, and a low-pass filter of 1kHz.

• The tweeter requires a high-pass filter of 1kHz, and a 14dB pad.

• Beyond these “starting point” settings, EQ to taste.  (You may enjoy some high Q boost around 50Hz, and some low Q boost around 18kHz.)

• If you're looking to build a passive cross-over, same general guidelines as with DSP.  Keep frequencies below 50Hz and above 1kHz out of the sub, and frequencies below 1kHz out of the tweeter.  (Use an L-pad for the tweeter, knocking it down 14dB to match the sub's output.)