Cone vs flat-bottom filter. Which is better?
What are the pros and cons of a cone vs a flat-bottom filter?ANSWER:
That's an interesting question. I don't think either drip cone filter shape is necessarily better than the other.
The thing to keep in mind is that the drip brewing process depends on the hot water coming into contact with all the coffee grinds and then dripping through to the carafe or the mug.
If the water rushes through without staying in contact with the ground coffee for long enough, the coffee will taste weak. If the water stays in contact for too long, the coffee starts to taste bitter.
I think different cone shape designs are chosen in conjunction with the design of the hot water spraying head. In other words, the combination of spray head and cone shape is optimized to soak the coffee thoroughly and for long enough to create a good brew of coffee.