Yes you can for songs you have made. you just have to be careful with using the name. you could say made with kds10 but not "Korg ds-10". Same with sampling the sounds for your use is okay but to sell a "korg ds-10" pack it is not okay. from my understanding as user. Companies don't want you making money off their name. A band called spiritualized lists all the guitars, pianos, effects, drums and amps etc they use and I have always wondered if they ask permission or the companies just get free promotion from the band?