PlayStation 3:

Following speculation that Sony was working on a 'slim' model, Sony officially announced the PS3 CECH-2000 model on August 18, 2009, at the Sony Gamescom press conference. New features included a slimmer form factor, decreased power consumption, and a quieter cooling system. It was released in major territories by September 2009. As part of the release for the slim model, the console logo ceased using the "Spider-Man font" (the same font used for the title of Sony's Spider-Man 3) and the capitalized PLAYSTATION 3. It instead reverted to a more traditional PlayStation- and PlayStation 2-like 'PlayStation 3' logo with "PS3" imprinted on the console. Along with the redesigning of the console and logo, the boot screen of all consoles changed from "Sony Computer Entertainment" to "PS3 PlayStation 3", with a new chime and the game start splash screen being dropped. The cover art and packaging of games was also changed.

Please answer a question about this article. If the question is unanswerable, say "unanswerable". What would customers notice about the sound of the new, improved heating system?
unanswerable