Video Demo --- IWISTAO 2 Way 6.5 Inch Labyrinth Empty Speaker Cabinet Enclosure 1 Pair Varnished Panel 7-shaped Structure InsiderThis empty speaker cabinet adopts a unique 7-shaped labyrinth structure inside, its plate is made of 18mm thickness high-density professional speaker MDF, which body is arc-shaped, and its front painted panel is thickened, and the exterior is quality PVC veneer. All handmade, high-end built.
The blog collects some tube models and give them a brief, also you can do a simple replacement, but for details, you need search them and get detailed parameters and curve.
Why some audiophiles like to choose electronic crossover, you may look at the following reasons. Of course, to use electronic crossover will consumes more power amplifiers, and one channel needs one amplifier.