They sound just freaking awesome, very deep and powerful bases, extremely precise high tones and clear middle.
I attached them just to the headphones output of the notebook, so they are obviously not very loud, but they have enough reserve for the amplifiers I build (I will show something new soon with lots of new equipment).
Speaker’s crossover contains of three parts: two-level low-frequency filter for the woofers, high-frequency filter and Zobel circuit for the tweeter. Physically woofers are separated by the hidden wall, so effectively lower speaker has more than 30 liters of the closed space, so acts like subwoofer with kind of phase inverter. Its output hole located at the back of the loudspeakers and produces very low tunes.
I do not regret any second spent building them, excellent sound justifies the efforts.