Cheradenine
Head-Fier
I don't think the venting makes much difference to isolation. I think the shell or housing design and eartip make the most difference, I mentioned it because its often assumed that vented makes it open backed. I find the A4000 isolation very good, similar to Etymotic er2 with Final E type tips in my ears, its improved with foam tips.Thanks for that.
The size of the ports or vents is not always directly related to the amount of isolation, which is where it gets tricky. Probably because of the internal architecture of the earpieces. Sometimes a single port is enough to let in a lot, other times there’s an entire grille but barely a peep gets through.
How is isolation on the E5000 compared to the E3000?
The E5000 is a similar design but a bit bigger, it doesn't have the perforated back plate, there is a vent but its hidden somewhere. In my ears the tip is the only point of contact, it holds the IEM in place with the housing sticking straight out from it like a joystick, much like the rest of the E series. It is very comfortable to use laying on my side with my head on a pillow, it looks like it wouldn't be but, the housing can move around like a joystick without affecting the sound because of the E type tip's design, rather than shove the IEM further into the ear. I don't have a massive collection of IEMs but I haven't heard anything that sounds like the e5000, it needs a lot of power, I don't mean some power station of a desktop amp, I just mean a decent dongle or portable amp.