As the title asks, I'm trying to get an idea of what is meant when people say this or that IEM (usually customs but not always) is more "pro oriented" or "better for use on stage". What exactly does that look like?
I have very little experience with IEMs apart from the Ety ER4S and the Westone W3. I know the Westone W series (for example) has been described as being for "home use" while the UM series and ES series are more of a "pro tool". But not everyone has the same take on what that means. Enhanced treble detail? Or more smooth and non fatiguing? Or more dynamic to help you hear your performance? I could see why various options would make sense, even contradictory options, so that's why I'm asking.