I’m just now listening to my Sennheiser IE600 IEMs after 40hrs of pink noise. The eartips are the problem so far. That is, the mediums isolate well but become somewhat uncomfortable after 30-40 minutes. The smalls are more comfortable but don’t isolate enough for proper bass extension. It seems my canals are somewhere in between.
The treble amount from these IEMs definitely need the mitigation the stock tips offer. However, 3rd party small bore tips that I've tried offer similar mitigation (e.g., Final E-type, medium), but they don’t offer intermediate sizes. I’ll be auditioning the small Final tips tonight, but I think I need to find & try other tips that offer intermediate sizes (e.g., medium-small, ~11.5mm dia.) that also offer a small or extended bore… possibly a good quality soft double flange(?)
Suggestions?