For me, its a speaker with:
Dayton reference 7" RS180-4 ohm + 2" Pioneer Cone tweet @ 3k
I went for the harmonics like a full range (same as flat woofer 1st order). Since I didn't have a $50 midrange handy, instead here's a 2 way with the pretty tone.
Woofer:
Inductor 15ga, caps electro, resistors 10w
0.68mh, 6.8uF, 12uF+3.3R, and it was that last step with an odd resistor value to "bury" the RC sound. WinISDPro tone sweep indicates no abruptness and that all output decreases after 2.7k. Free 1 cu ft enclosures, ported.
Tweeter:
Resistors are 5w, smallest caps are polyester.
Pass+ with 1uF and parallel pass with 33R+8uF (adjust tone)
Shunt 0.37mh 18ga
Shunt 20R (adjust volume)
Pass+ Nichicon ES 10uF//100nF
Pass- 3.3R
Use:
On top of the kitchen cabinets! Finally returning music to the house since the TV overtook the living room. But, washing the dishes is now a fantastic event. Rock on!

For me, its a guitar amp with:
1 x 15" and 1 X 12" driver connected in 16 Ohm with zero passive XO
4 input mixer
6 preamp modules
3 way tone control
all small signals powered by 2 x 12 rechargeable lead acid batteries
A trickle charger that charges the batteries when amp is powered off
Power amp for guitar from Rod Elliot on +-33V

I made it for my son who plays Guitar with background music from his PC to help him practice his rifs

Currently working on the Circlophone projects designed by Elvee.
The amplifier is a solid state discrete with excellent dynamics and very good clarity, but I would like to revise that sonic signature a bit. The odd benefits include a sort of noise gate function and the music always sounds like a live performance. I can't explain it. But it is a fun thing.