I have purchased from Buy Extras.com two identical cooling fans(exact replacement..size wise)for 15.00 Pop the top and replace..so easy...and a noise floor of 16db...quiet! YOU VOID ANY WARRANTY DOING THIS! I am not concerned as in my home I never have had my 202 over 5 notches, can't handle the volume with such efficient speakers (Altec Lancing model 14's and 15's). Any heat exhibited is Definitely a problem. Read your owners manual or download info from this site "CROWN AMPLIFIERS IN DEPTH". Everything you'd want to know! Geenie. ______________________________________________________________________________________________________________ After 1 year of owning the XLS 202 I myself am noticing "increased" high pitch fan noise which is annoying to say the least, probably due to excessive dust on the fans, as there are no protective dust filters on the XLS series. Id like to do the fan mod too, though would like more spec info! Do you think it would be worth getting a fan with a built in speed controller as well as being a lower db fan for even lower noise levels? as seen on many PC mods. I for one have never had hot air blowing from the 202 Fans, hence doubt circuitry would ever get damaged! I expect on higher output amps like my XLS 802 for instance, adjusting the RPM to a lower level could possibly be fatal due to heat dissipation problems, having said that it should not effect anyone shopping arround for a superior fan with a lower db output as long as the RPM remains the same!