Good sub with weaknesses

I have these subwoofers are about 4 weeks in operation and I must say that he has an excellent price / performance ratio. Unfortunately, I have not bought it here at Amazon. Who has space in the cinema room, will not interfere in its size.

Positives:
- Plays punchy and clean with music and film
- In conjunction with other Klipsch speakers results in a great sound

Negatives:
- At low frequencies from about 26/27 Hz arise in my air noise when bass reflex duct the bother. This can other manufacturers such as. SVS better what is justified also by a higher price.