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Thursday, November 18, 2010

Approval from Etymotic Research!

Today, I had a conversation with Mr. Jonathan Stewart, the Engineering Manager, Quality & Regulatory Affairs at Etymotic Research, on the phone, and he verified & approved my blog article regarding the proper insertion depth of insert earphones. After sending a crap load of emails to college professors & audiologists, DIYing a coupler, reading through journal articles & industry standards, my few years worth of effort has finally payed off!

And this also means that most of the IEM manufacturers have been hiding the most vital part of the equation in using IEMs- proper coupling of the earphone and the ear itself! Usually, conventional IEMs, especially custom-moulded ones, reach no deeper than the 1st bend due to technical difficulties & safety reasons. This kind of shallow insertion would not secure the residual ear canal volume of 0.5cc, and cause some degree of linear distortion on IEMs.

Thus, I blame *erry Har*ey, the founder of *l*im*te Ea*s & J*au*io and Wes*one, for causing all these! (At least Etymotic Research and Shure have long eartips available for deeper insertion)


  1. Yeah! That one was a beautiful article. You are my Hero. Thanks

  2. I was under the assumption that most custom IEMs were molded to go past the second bend in the ear canal. I seem to remember reading on a couple of manufacturers' ear molding guides that the audiologist is supposed to inject silicone past the second bend in order to produce a deep inserting custom. Any comments on this?

    1. And I asked the same question to the engineer at Westone; He said that it is all up to the size of one's ear canal. The bigger the mould comes out, the deeper the insertion depth becomes. This is not good..

      And let's not forget the 2nd-bend is only a general rule of thumb. Unless the ear canal's volume is precisely measured, you can't never figure out an ideal insertion depth.