What is the difference between open and closed-back cabinets?
The closed-back type of cabinet has much more bass presence and a tighter feel. The sound is more directional, however, and can feel slower or less free and open. An open back gives a looser low end with less depth, and ‘figure 8’ directivity (sound field looks like an 8 when looked down on from above the cab). Sealed boxes give tight, deeper low end but are more directional, giving less spread of sound.
