Which Manufacturer makes the quietest air pump?

Any suggestions?

Thanks!

Gary
My Whisper 100 seems to get quieter everyday! Its been running now for 2 months and unless I stick my head inside my stand, I can't hear it at all! Hope this helps:)
 
The Whisper 10 Air Pump is so quiet, That the sound of my breaths are louder than it, even though it's about 2 feet away.
 
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