D e s i g n . C o n c e p t :

Deep & Powerful yet elegant & stylish, a subwoofer to be seen.

Update:

I have now changed my design to a sealed alignment in a similar looking smaller enclosure (shown left). All sides will be curved in this design, the only exception is the front baffle.

The driver

Stryke Audio AV12

Although tempted by the bang for buck of the AV15, I find that 12" subwoofers usually strike a more attractive balance between output and acceptable size. It is attractively presented with an aluminium cone and inverted dustcap.

It has almost as much VD (volume displacement) as the 15" Adire Tempest, while it works well in a smaller box than the 12" Adire Shiva. The downside is that more power is required.

The extreme excursion capabilities of this driver are shown in the animation on the left. The driver is moving at its xmax limit, however in real life it looks even more extreme.

Choosing an alignment

Orignally I had planned to use a 70 - 85L vented alignment (shown in the animation) for maximum output and linearity for home theatre. However, to get the benefit of this requires a lot of power, which is expensive. Simulations indicate I can get 114 dB above 25 Hz with 400 watts each to a pair of sealed AV12 subs. This will reach xmax limits. To achieve only a small amount of extra output I need vented boxes twice the size with a much more expensive amplifier capable to at least double the power. I suspect I would be evicted from my residence before I could get away with listening to that kind of output! What the images here don't show you is that the smaller sealed box looks much more elegant next to my TL speakers than the vented version.

Box design

The box is to be constructed of MDF. The curved walls are to be built up from 3mm MDF. The internal bracing will act as formwork while the 3mm MDF layers are bent and glued. To compound curve on the top is a challenge that I'm currently investigating.

Progress

I currently have the drivers in 70L prototype boxes. I have tried both sealed and vented alignments and was surprised to find the differences to be less than often described. For music, the difference can be hard to tell. I also have a H frame dipole to test. Progress has halted as I need to get a new amp.

I will post more information on this site, including simulations, measurements, pictures, and discussion when the sub is completed.