Apple Pro Speakers were introduced with the Power Mac G4 (Digital Audio) and later shipped with the iMac G4. These speakers required a Mac with a built-in amplifier and a proprietary audio jack to connect.
Apple described these speakers as “designed by Harman/Kardon,” once a high-end audio company now owned by Samsung. Harman/Kardon also designed the popular iSub subwoofer and SoundSticks in partnership with Apple that were released in 2000. In both the Apple Pro Speakers and SoundSticks, Apple contributed the industrial design and mechanical engineering, while Harman/Kardon manufactured the audio components of the product.
Sources: MacWorld, Wikipedia.org
