ForceMajeure
1000+ Head-Fier
- Joined
- Jan 19, 2014
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Being the co-developer of the apex module, I can maybe help explain this phenomenon. There are a couple things at play. The reason the customs have modules that sit deeper or can vary between left and right is in the manufacturing tolerances. The universal shells and custom shells are made with totally different methods. The U's being machined precisely and custom shells worked on by hand. If you have a wood faceplate etc. your distance from the shell is higher, the bottom of the module socket is most likely fixed in the shell. That explains the height differences. It is very unlikely that this is the cause of ambient/bass differences. As far as your bass sound difference, there is also module tolerance. According to 64’s 1db swing explained by Chris couple years ago, it’s entirely possible your particular set of m20's are on the lower swing, and your m15's are on a higher swing. This could lead to less of a gap between them. There is only a 4db bass difference between them at nominal readings Its not a whole lot. I've verified this on my ear simulator. Also consider IEM tolerances. When I clean ears and test them, 64 and JH seem to be the closest between L and R. So, it’s a smaller factor in this particular case IMO. Another variable could be the DD being back vented to the outside of the shell. That can let some ambience in as well, this can differ from BA vented in a confined shell space. I've used future sonics for years and it’s almost like an ambient port. In a post ahead of this someone mentioned internal apex. There is no ambience rating on the 64 website for “internal apex”, I've also verified this on my measurement mic that there is only a 1/2 db bass drop with the fourte's internal apex. vs m20 being a 4db drop from closed to open. There's also factors that can affect FR between universal and custom ears. The volume inside your canal is important. This is an age-old question on why a demo can’t sound identical to a custom. U's generally sit on a shallow insertion meaning more volume inside the ear. Customs go deep which leave you with less volume. If you've ever put universals in your ears and pushed them in really far, you will hear the sound difference. If it’s not front vented you will be stiffening the air inside like when you experience a drastic elevation change. With front venting this effect is drastically reduced if not eliminated, but the removal of volume inside will still affect the sound. Definitely a conversation best had over a beer and not the internet.
Let's grab a beer then
