The styling of our hi-fi gizmos is a topic near and dear to my audio passions. Here is a thread to discuss Industrial Design for High End Hi-Fi and post what we think are good examples.
Here is one way to define ID:Industrial design
is the professional service of creating and developing concepts and specifications that optimize the function, value and appearance of products and systems for the mutual benefit of both user and manufacturer.
As a start to this thread the industrial design profession web site Core77 has noted the Astell&Kern ACRO L1000 and made some nice comments. Extra large volume knobs with lots of knurling do seem to have an allure.https://www.core77.com/posts/98718/A-Beautiful-Object-AstellnKerns-ACRO-L1000-Desktop-Headphone-Amplifier