Quietest fan for room

The cheapest AND quietest way is to mount PC fan onto the chassis of hot component(I believe amp). You will need to ID available DIN for fan and measure the voltage between terminals in order find proper fan. Than it's only mechanics to mount the PC fan or couple onto the chassis.

Plan B: If you have wife or GF, you can get pheasant feather fan and give it to her while listening:-)

large block of Ice in tubs

Options are truly unlimited... How about some freon cooling system?

I now run cold central AC, but apperently vents ARE noisy so all I can do is to CRANK IT LOUD or sweat under the heat wave and listen quiet.