Well, why not? OK, here's the short answer list:

  1. Fans are noisy
  2. Water cooling is quiet
  3. It's very efficient
  4. This amp needs superior cooling for thermal stability
  5. If you do it right, water cooling is safe, easy and clean

At the right, you'll see my simple water reservoir and pump, sitting on a shelf underneath a table in my office. The submersible fountain pump is the little blue object immersed in the Rubbermaid 4.5 gallon food container, which is filled with 3 gallons of distilled water; 1/4" I.D. vinyl  tubing brings the water to and from the RF deck, and the power cord plugs into the large power supply on the floor beneath it.

After an hour of talking a lot, the water is lukewarm, but that's about it. A more elegant system is planned; I built the power supply chassis oversized to allow room to house a copper heat exchanger, pump and reservoir. But this is fine for now.

By the way, if the XYL doesn't like the idea of a 3 gallon tub of clean distilled water under your desk, and your relationship with her is good, you can mention that 25 gallon fish tank in the living room, complete with water and air pumps, fish food and algae.