Originally Posted by ebrian
Can I have someone quote this message with a straight response -- vacuum seal <-- this is a bad thing?
I've always strived to have vacuum seal on all my iems. I was disappointed when the Heir tips for my KC06 couldn't give me this type of seal. It was just sitting outside the canal and I only stuck with it because the bass was so drastically improved. So you're telling me that this is the *ideal* setup; sitting snugly outside the canal?
I think we need to define "seal". What you normally want to strive for is no vacuum, in the sense that there is no "sucking" sensation pulling the earphones inward or the eardrum outward. Essentially, you want a tight seal in that no air can escape. So in that regard it is like a vacuum, sort of like space. I think what most people refer to as a vacuum is actually a seal that causes negative pressure to pull on things. This is usually bad. I always get the best possible sound when I have any earphone air tight, but with no negative or positive pressure at all, simply a neutral vacuum. Still, pressure-less air trapped in the canal.
Pushing an earphone tip into your ear that is already air tight as it enters will cause pressure buildup. Sometimes, just waiting a while will allow the air to slowly seep through the tip seal and equalize pressure. Sometimes, with something like the er4s, this never happens for me. So it becomes imperative that I insert the tips with no pressure to begin with. The usually involves me breathing on the tips and rotating them while inserting them. Sometimes with the er4s I even need to bend them sharply once they're in until I create a break in the seal. That equalizes the pressure while the tip is already pretty much in my ear, and thus the sound is correct.
I'm sure there are other methods, like pulling up on your ear. I do this too sometimes, but the whetting with my breath is more effective. It seems like it would cause a worse pressure buildup, but because the slight moisture lets the tip slide smoothly, it seems to build up pressure less.