The Yuin PK2 Earbuds are low impedance earphones with a sound signature similar to that of the PK1. Unlike the PK1, the PK2 doesn't need a headphone amp to drive to the fullest. It produces a transparent smooth sound and is designed to resemble a traditional earbud.
This is a companion discussion topic for the original entry at https://apos.audio/products/yuin-pk2-earbud-earphones