To finish the article I posted regarding the Denon DHT-500SD, I wanted to share my experience so far with the DHT-550SD. This set does not have a fan in the receiver. The set consists of a separate DVD-player and AV-receiver and active subwoofer. It is clearly a more 'professional' audio system. First thing I noticed was the sound quality. It sounds even better that the 500SD. Especially the tuner (although I primarily bought it for DVD). The low frequencies 'feel' better than with the 500SD. It has more sound-possibilities and combinations, virtual surround, etc. Also the number of in- and outputs are enormous. Most important for me is that I can look and listen to DVD with silent passages without whistling fan noise. But I must say that the 150,-- difference is totally worth it. I can only recommend anyone who thinks about bying it (or the 500SD) to check it out and go listen at a reseller if you are not yet convinced.