I apologise as I have not had time to read all the responses to your question about image height but this article was published in the Absolute Sound and was part of a series of articles about being able to determine the best digital audio music files - wav/flac etc - and computer file servers - windows/Mac. The writers of the artiicles used image height as a 'measurement' of sound quality - the higher the image the higher the quality. I use this method - not in a measured way - but listening for the height which equates to me as better/best sound quality. It usually correlates to high frequency content and higher or highest resolution in the music being played. The article - one of them is here - if you scroll down until you find image height the context can be read. Hope it helps?