Acoustic Elegance PB12 dual opposed sub

This weekend’s project was to change a 6^th order bandpass sub into a dual opposed sealed sub with the Acoustic Elegance PB12 driver. 

This sub belongs to Roger (Antripodean). The original wasn’t designed with the driver in mind and had a very limited bandwidth. It contributed very little to Roger’s system. 

So we blocked up the vents and cut the necessary holes. The net volume is around 80L.

The driver has a poly cone, cast basket and a high quality motor.

Nearfield response:

You can see how the response is quite smooth and extended for a sub driver.

Farfield response when integrated into the system: 

We placed the sub in the middle of the front wall and ran some quick measurements to integrate it into the system. Initially we ran it up to 300 Hz and there were some localisation issues. The integration was better with a 200 Hz crossover and I tweaked the target curve a little more prior to the last measurement to increase the bass level. The lower midrange was a little tubby at first.

The final result was quite good and it performed well and made a good account of itself. One thing I did notice was the lack of cabinet vibration as a result of the dual opposed mounting arrangement.