Open baffle speaker
There are many different speaker concepts and we tried most of these. The main problems is coloration (distortion), this is usually caused by multiple standing waves of the same frequency within the speaker enclosure. Another issue is compression of air and the given slip between fixed magnet and moving voice coil. In other words when we apply a certain voltage, the voice coil moves to a certain position. But if we apply slightest mechanical force on the voice coil we can change the position of it, regardless of the applied voltage. So even when we manage to design a perfect speaker cabinet, we can't eliminate the asymmetrical load (compression) on the voice coil. This will always cause some distortion. With open baffle speakers we don't have these problems. The main problem with open baffle speakers is bass. This problem can be fixed using multiple bass units that compensate for the baffle step (loss of lower frequencies with finite baffle size). We ended up using one 8" full-range speaker and two 15" bass units. The baffle could be kept relatively small so it's not too intrusive.