This project started life as an experimental bandpass enclosure. I built it using two ten inch drivers in isobaric configuration. The original tuning meant it should reach a -3dB point of around 16Hz. In fact, when I measured it I found a -3dB point of 14Hz. Very nice, however the efficiency was so low, and the actual acoustic output was so low that it was unusable in practice.
For the coffee table design I took the sealed bandpass encloure and chopped the end off! I also altered the vent arrangement to produce a fourth-order rolloff. I used large, four inch drainpipe to reduce the possibility of chuffing at high volume. The result is something quite usable and useful!
The top of the table is made from recycled Rimu, a native New Zealand wood.
