This is in response to our valued customer and member of the 64 audio family @crinacle, as well as @echineko and the rest of the Head-Fi community.
First and foremost, we are very sorry to hear about your experience with your custom N8. We want to help and will do everything in our power to rectify the situation.
We believe with all such situations there comes a silver lining. That silver lining is the opportunity to learn, to improve, and ultimately, to make our customers happy. After thoroughly investigating on our end, we believe we understand why this happened and will confirm when we get the unit in for investigation and repair.
To answer questions regarding the tuning as seen in @crinacle’s custom pair, and whether it is intended going forward, the answer is, no. This was not the intended tuning. The two sides matching could be the result of performing the same process to both sides during production. Our demo units provide the intended sound signature and we translate that signature to all custom units. The custom and demo should look very similar across the frequency spectrum.
The N8 is a special product in our lineup. It shares a tubeless low frequency dynamic driver similar to our Fourte and Trio products. After thorough investigation, we believe that the discrepancy in sound signature is most likely caused by a difference in air volume inside the shells. In the design stage the original tuning of N8 was achieved with a representative internal air volume of the shell based on an average ear size. This translates consistently to the demos because they use a universal shell that is properly sized for this average internal air volume. Early on, we suspected that there could be changes in the low frequency response of custom N8’s depending on the actual air volume of shells among different customers. However, we ran tests in the development stage that showed only slight variances among different shell volumes that fell within our established tolerances..
Although more investigation is needed, it is possible that
@crinacle’s ear shape yielded an internal volume of air that is beyond the predicted ranges that we designed for. The FR deviation we are seeing from the measurement supports this, but again, we will investigate further once we receive the units.
At the end of the day, we have a customer that is not satisfied and that’s not ok. We are hoping that this initial response helps shed some light on a possible explanation while we dig further. We will follow up with the community as soon as we know more.