My C4s arrived today, in transit for 7 days, 3 to get to Sydney, another 4 to make the 450k down the coast to me.
Really pretty cherry red jewels. They're a rather tight fit, but a few stiff raps with a rubber mallet quickly solves that. The isolation is very good, however it's a bit of a challenge to pry them out. Fortunately I found out, quite by accident, that if I sneezed they would pop right out.
Ok, I'm joking, they appear to fit just fine.
Quite snug, good seal. I say 'appear to' only because this is my first set of CIEMs and I'm not really sure what a good fit is like. I've haven't worn them enough to tell if they're too snug, and would be uncomfortable for extended listening.
But I don't think there's going to be any problem with the fit. The problem is with the sound. When I first put them in and heard the sound I thought something was wrong. I checked that they were all the way in and seated properly: they were.
The first piece I listened to was Schubert's String Quintet performed by the Lindsey Quartet. Great playing, very nice recording, I'm very familiar with both. The instruments sounded vague and muffled compared to my reference UIEMs. The individual voices of the violins, viola and cellos lacked some of their unique qualities. The cello lost its throaty growl in the lower register. There isn't the space around the instruments and the notes seem to lack attack and clarity. The difference between the C4s and the reference UIEMs were not subtle but marked.
Going to very different music, the Dance of the Coachmen and Grooms from Stravinsky's Petrushka, the problems mentioned aboved were present but the 'bloat' was more obvious. The music lost its sparkle and drive.
The 'reference UIEMs'? The Fitear F111s I bought recently. I love them, they do everything I want. At this point I'm very disappointed with the C4s. I'm going to try 'burning them in', see if that makes a difference although I haven't found any mention in this thread that they require it. If not I'll contact Frogbeats and see where to go from here. Not sure I want to spend more time and money pursuing the C4s as an option, especially since I'm finding the F111s so enjoyable. It really puzzles me that my experience should be so dramatically different than other far more experience people on this forum.