The JBL research department has found out how to make practically noiseless air pumps even more silent. We were able to improve the dedicated shape of the rubber feed of the a100 and a200: instead of two small pins connecting each foot of the pump to the ground, we installed modified feet with only one pin. Both the a300 and the a400 still have 2 pins, but they are now made of silicone like the new ones. This small change has resulted in a surprisingly high reduction in resonance noise.
The JBL ProSilent Air pumps are maintaining their position at the top of the air pump sector!